DIY flat roof repair. Subtleties of current and major repairs of flat roofs. The main advantages of the work of Innovation Group of Companies

Repair of flat roofs is becoming increasingly in demand these days, since this roof structure is very widespread not only in multi-storey buildings, but also in individual construction. Its benefits are quite obvious. A flat roof with a small angle of inclination allows not only to save thermal energy, reducing the heat transfer area. It allows you to use it for domestic and economic purposes, thereby increasing the usable area of ​​the entire building.

Before you begin repairing a flat roof, you must study all the rules and requirements, since mistakes can lead to a shortening of its service life.

However, this use also has a negative side. It greatly increases the risk of damage to the roofing, primarily mechanically. Meanwhile, a flat roof, despite its apparent simplicity, is a rather complex structural system.

That is why flat roof repairs must be carried out in strict compliance with a number of rules and recommendations. Their violation can lead to a radical reduction in the service life of the roofing, up to its complete destruction.

Flat roof installation and possible types of damage

Before you begin repairing a flat roof, you need to know its structure. Then the weakest points of this particular structure will be clear, and it will be easier to identify the cause of the roof leak. Usually its design consists of several layers. This is a load-bearing surface, the role of which is a reinforced concrete floor slab, on which a vapor barrier layer is placed, and on it, in turn, insulation.

The latter is most often used mineral wool. A layer of waterproofing is laid on it, which in most cases is played by rolls of roofing felt.

If the roof surface is occupied for economic or domestic needs, a concrete screed is made on top of the waterproofing layer, designed to protect it from mechanical damage. In addition, to prevent moisture condensation from the insulation layer, ventilation holes are vented outside, covered with special caps. Their connections with the top layer of waterproofing must be sealed carefully.

The main reason for the penetration of moisture under the waterproofing layer, in addition to mechanical damage, is the effect of temperature changes in the surrounding atmosphere. The second most common cause of roof leaks can be considered a violation of technology during the initial installation of the roofing.

It is worth remembering that the service life of a roof covered with roll materials such as roofing felt is limited to a maximum of 5 years.

In winter, under the influence of severe frosts, it begins to lose elasticity and crack. In summer, thanks to its black color, it attracts solar thermal energy and heats up to 70°C.

As a result of this, the resin impregnating it begins to melt and gradually slides downhill to the edge of the roof.

The base that remains in place largely loses its waterproofing properties and gradually begins to let moisture through.

Modern waterproofing mastics and resins have a significantly longer service life, but are also much more expensive.

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Roof repair using roll materials

Rolled bitumen materials are the most common and popular roofing product, primarily due to their affordable price. Another reason for their popularity can rightfully be considered that their use does not require dismantling the old coating. However, you should not immediately lay new rolls on top of the old coating. It must be prepared in advance.

First of all, it is necessary to remove debris and dust accumulated on the roof. After this, the formed air bubbles are identified on the roof. They are opened with a knife like an envelope and, if necessary, dried. After this, they are heated with a blowtorch until the bitumen impregnation melts and closed, eliminating air bubbles.

Only then can the next layer of rolled roofing felt be laid. The roll is rolled out on the roof surface, one edge is heated and glued to the bottom edge of the roof.

After this, they roll it back up, winding it onto a piece of pipe that is slightly longer than the width of the roll.

Then they begin to slowly unroll it, heating the surface with a blowtorch. An indicator of the quality of heating is a small puddle of molten bitumen along the roll unrolling path.

The next roll in the longitudinal plane must be laid on the previous one with an overlap of at least 10 cm.

The adjacent roll must overlap the edge of the previous one by at least 5 cm. As a result, if the technology is followed correctly, after the molten bitumen has cooled, a monolithic waterproof membrane is formed, covering the entire surface of the roof.

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Application for repair of polymer materials

Most modern materials intended for waterproofing are made on the basis of polymers. If it is mastic, then its main component is liquid polyurethane. Its first layer is applied directly to the prepared surface using a paint roller. It adheres tightly to the bitumen base. Then a reinforcing layer of non-woven synthetic fabric with a density of 20 to 60 grams per m² is placed on the not yet hardened mastic so that it is completely recessed. After this, a second layer of polyurethane mastic is applied on top. The hardening process lasts from 3 to 5 hours.

Another effective modern waterproofing material is liquid rubber. It is applied by spraying using special portable backpack sprayers. The main advantage of this method is that it is not afraid of any unevenness on the roof surface. To obtain a rubber coating with a thickness of 3 mm, it is necessary to spray from 4 to 4.5 kg per 1 m². The resulting membrane is resistant to temperature changes, but in severe frost it loses its elasticity, which makes it more susceptible to mechanical damage.

Another product that is becoming increasingly popular these days is tension polymer membranes. They are assembled using welding machines that connect the joints with hot air, and are attached only to the edges of the roof. Therefore, if the foundation of the house begins to subsidence, the coating will maintain its integrity. However, as with previous materials, membranes are also vulnerable to mechanical damage, so if the surface is intensively used, a protective coating must be placed on top of the waterproofing.

The simplest protective coating, especially for coatings made of rolled materials, is a concrete screed. Unfortunately, over time it begins to crack and crumble. There are very good reviews about the high-strength polyurethane coating Marisil 400, but many are put off by its high price

In general, it can be noted that the repair of a flat roof, unlike its other varieties, is practically not associated with a risk to life and health, and therefore can be done with your own hands, without the help of hired specialists.

The coatings used for flat roofs have a long service life. However, most roll and membrane materials have to be changed before the stated service life has expired. This is largely due to the occurrence of various types of damage that form on the roof during its operational life.

Types of roofing damage

The main reason for damage to the roofing carpet is the poor quality of installation work and the use of cheap materials, the quality of which does not correspond to current operating conditions. Lack of regular maintenance also leads to both minor and critical damage that requires immediate repair.

The most common types of flat roof damage include the following:

In order to prevent the condition of the roof covering, it is recommended to conduct a routine inspection of the front surface of the roof. If problems are discovered, a decision must be made on how to proceed with repairs to prevent further damage.

Flat roof repair methods

Depending on the type of defects and the area affected by the damage, restoration and repair work on flat roofs is usually divided into the following groups:

• current repairs are local work performed when minor defects and damage are detected in the roofing system. Basically, the damaged roof covering is partially replaced, peeling and swelling are eliminated;
• major repair - is a complete replacement of the current insulating layer and roofing material, including a full cycle of preparing the working surface for further laying of a new coating.

The basis for major repairs is the presence of damage of various types on more than 40% of the total area of ​​the flat roof. Unlike local work, major repairs require the investment of a significant amount, which is comparable, and in most cases exceeds the cost of laying a new roofing cover.

What material to use for repairs

The technology for installing and repairing flat roofs involves the use of various materials. The use of a particular material is determined by the current condition of the roof and the coating that was laid or applied previously.

Major repairs of flat roofs are carried out in all cases where more than 40% of the total roof area is damaged

In general cases, the following technologies are used to repair flat roofs:

• repair with screed - used in cases where the concrete floor slab is severely damaged and a full-fledged thermal insulation pie is required. In this case, a vapor barrier membrane, mineral or foam insulation, fine expanded clay, concrete mortar, primer and insulating coating are used for repairs. To mix the solution, it is recommended to use sand concrete M300, produced under the trademarks “Polygran”, “Master Harz” and BESTO;
• repair using roll coverings - used for restoration of flat roofs of various configurations. Various analogues of roofing felt or PVC membrane are used as roll coverings. Among the bitumen roll coatings, one can note the products of the TechnoNIKOL corporation under the brands Stekloizol KhPP-2.5, Technoelast KhPP and Uniflex EPP. As a roofing polymer membrane, it is better to use a coating under the Ecoplast V-RP or Logicroof V-RP trademark. To work with roofing felt derivatives, you need a gas burner, and to lay PVC membranes, you need an adhesive composition and a hair dryer;
• repairs using liquid rubber - most often performed when servicing multi-story residential buildings, since the applied material is light in weight and does not weigh down the floor slab. For use, we can recommend waterproofing under the brand name “Technoprok R”, Euromast Plus and Tremproof 250. Liquid rubber is applied using a special industrial sprayer. In addition to the insulating material, vapor barrier, thermal insulation coating and deflection are used.

When repairing a roof with a screed, it should be taken into account that in order to mix a sufficient volume of concrete, you will need a concrete mixer and a large number of containers for transferring the concrete mixture. To distribute concrete, it is necessary to set linear guides. Leveling the solution is done using a steel rule.

In order to understand in more detail the technology of working with various materials, we will consider the process of repairing each type of flat roof separately. A more general technology describing the process of current and major repairs will be discussed below.

Repair of roll roofs

Roll coatings under the trademarks Stekloizol KhPP-2.5, Tekhnoelast KhPP and Uniflex EPP, which were mentioned above, are modern bitumen roll materials. For their production, a binder composition based on bitumen and filler is used, which is applied to fiberglass on both sides. Asbagal is used as a protective front layer - a coarse-grained coating applied to a special polymer film.

TechnoNIKOL Corporation produces a wide range of roll-bitumen coatings for roofing

As a rule, Stekloizol, Tekhnoelast and other bitumen roll coatings are used to protect flat roofs with preliminary installation of a concrete screed. The main problems of this coating are the formation of local damage in the form of cuts and cracks that occur as a result of improper use of the roof. If the operating technology is violated, air and water bubbles may form.

To eliminate local defects, patch repair is used, when the damaged area is completely covered with a new canvas. The size of the patch directly depends on the area of ​​damage.

Repair of cracks, breaks and other surface damage is carried out as follows:

If it is necessary to eliminate swelling and bubbles on the surface of the rolled coating that arise due to seasonal temperature fluctuations, then it is necessary to carefully cut the damage crosswise.

Next, you need to bend the corners of the coating so that you can dry the inner surface. After drying, the surface is cleaned and treated with bitumen mastic, and the bent edges are pressed back. Then patch repairs are performed using the technology described above.

Repair of membrane roofs

PVC membranes are a specialized waterproofing coating designed to protect roofs and concrete foundations. The extrusion method is used in the production of membranes. This ensures that the final material will have zero water absorption.

Mechanical damage and depressurization of seams are two main problems that arise during improper use of a flat membrane roof. For example, when removing snow carefully with an iron shovel.

A special welding machine is used to lay the PVC roofing membrane

To repair mechanical damage, you will need to perform the following work:

1. The damaged area of ​​the membrane fabric is cleaned and treated with an organic solvent.
2. A patch is cut out of a single membrane sheet, the size of which will cover the gap or other damage on the surface of the roofing carpet by 5–10 cm.
3. The patch is laid on the prepared area of ​​the roof and soldered using a welding machine. While heating, the patch is gradually smoothed with a roller.

Depressurization of seams occurs due to a violation of the technology for laying PVC membranes. As a rule, the membrane is poorly heated or placed “under tension” to hide irregularities.

To repair, you will need to treat the inner surface of the peeled seams with a solvent. If necessary, they should be cleaned using available means. Next, the seams are soldered with a welding machine. If the length of the peeled seam exceeds 5–7 m, then it is additionally taped with Eternbond repair tape.

Video: installing a patch on a membrane roof

Repair of mastic roofs

Liquid rubber, unlike bitumen roll coatings and roofing membranes, allows you to create a seamless roofing carpet. This is especially true for flat roofs of old buildings, where preliminary installation of a concrete screed is impossible due to the load it places on the load-bearing elements of the building.

Liquid rubber for roofing is a two-component composition that is mixed before application to the surface.

The main damage to a mastic roof is cracks that occur during long-term use of the roof. To repair them, liquid rubber of a similar composition to that previously applied is used. For example, liquid rubber “Slavyanka” for roofing is a two-component composition that is applied using a high-pressure unit and a spray nozzle.

The technology of roof repair using liquid rubber is a combination of the following operations:

If there is extensive damage to the roof surface, then first of all it is necessary to eliminate local holes in the roof. After the restored areas have dried, a second layer 3–4 mm thick is applied. If necessary, fiberglass is laid and a finishing layer of liquid rubber is arranged.

Video: spraying liquid rubber on the roof

How to make an estimate correctly

Before carrying out any repair work, you should calculate its cost. To do this, you will need to draw up an estimate in electronic or paper form. This will avoid shortages or excess consumption of building materials necessary for repair work. Especially if major renovations are planned.

If there are swellings in the roofing covering, a cross-shaped incision is made with further processing of the damaged area

In order to create an estimate, you must complete the following steps:

• measure the working surface - using a tape measure and other tools, measure and inspect the working surface. Based on the data obtained, the total surface area in need of repair is calculated;
• calculate the quantity and cost of consumables - based on the current condition of the flat roof, the type of repair that is planned to be carried out is selected. Taking this into account, consumables and tools necessary to carry out this work are selected;
• calculate the roofing covering - according to measurements and technical condition, the covering will be selected to be used for repairs. Based on this, its quantity and cost are calculated;
• draw up a work plan - at this stage it is necessary to think about how the material will be delivered to the site and the sequence in which repair activities will be carried out;
• adjust the amount of consumables - the previously obtained volume of consumables must be increased by 15 to 20%. This will allow you to make a reserve for errors in cutting and accidental damage during repair work;
• choose a construction store - prices are monitored in construction markets and in stores represented in your region. If possible, you can contact the store directly with your estimate. The costs of delivery and unloading of the material should be added to the final cost.

If repair work will be carried out by qualified workers, then the corresponding item should be included in the estimate. It is not recommended to purchase specialized tools for performing work for personal use. It is more rational to rent it. Especially if a major overhaul is planned in compliance with technology.

Current flat roof repairs

Routine repair of a flat roof includes work aimed at eliminating local damage in the form of cuts, breaks, cracks and blisters. In essence, these works allow you to quickly eliminate local damage without affecting entire sections of the roof.

Basically, current repairs are carried out in case of damage to the soft roof, for the construction of which bitumen or membrane coatings were used. You can perform routine repairs yourself without turning to specialists - you will need a minimum of tools.

For the construction of soft roofs, a bitumen-based roll material called “Stekloizol” is most often used.

As an example, we can consider the technology of current repairs for various local damages. To carry out the work, you will need bitumen waterproofing material (glass insulation, euroroofing felt, bikrost), a gas or gasoline burner, a sharp knife, a rolling roller, and cold bitumen mastic.

The general technology for repairing extensive damage to the surface of a flat roof is as follows:

When using roll coatings with a built-up surface, the installation technology is similar to that described above, with the exception that a construction hair dryer will be required to install the patch. The working surface of the cut patch is heated with a hairdryer until the bitumen layer becomes soft. Then the canvas is carefully laid over the gap and ironed with a roller.

The technology for eliminating cracks and minor damage to the canvas (15–20 cm) is similar - the damaged area is cleaned of protective coating, after which mastic is applied and a covering patch is glued. In this case, there is no need to cut out the damaged fabric.

Video: Installing a Fused Patch

Major flat roof repairs

Major repairs, as specified in the section above, are advisable to carry out when damage and defects are present on more than 40% of the total area of ​​the flat roof.

The essence of a major overhaul is to completely replace the current roofing material. If necessary, a complete replacement of the roofing pie can be carried out, including steam and thermal insulation, as well as screed.

Dismantling of the roof covering is carried out using special equipment

As an example, consider a major repair of a flat roof with further installation of a weld-on roll coating. To complete the work you will need a seam cutter, a chipper, a concrete mixer, a gas burner, a shovel, a laser level, and a metal rule.

The overhaul technology consists of the following:

1. The damaged roll covering, PVC membrane or liquid rubber is completely dismantled. For this, a grinder, a wall chaser and a sharp ax with a metal handle are used.
2. The working surface is cleaned using hard brushes, shovels and grinders. The removed roofing felt is cut into small sheets and then stored in a separate place. Where possible, the dismantled material is transported to a landfill.

   
   After dismantling, the old roofing covering must be taken to a specialized landfill

3. A visual inspection of the working surface is carried out, during which its technical condition is determined. If the surface is represented by a concrete screed, then in most cases it must be dismantled.
4. The concrete screed is being dismantled. To do this, the concrete surface is marked using a joint cutter. To remove the concrete layer, special bumpers are used.
5. Construction debris is removed and the roof surface is prepared for pouring concrete screed. Shovels, brooms and other equipment are used for this. After cleaning, the surface is wetted with water.
6. Linear guides are being installed. For this purpose, special steel beacons are used, which are mounted on dowels or a cement-sand mixture. During installation, a slope (3–5%) is maintained from the center to the edges of the roof or vice versa.

   
   The roof screed is carried out along pre-arranged guides

7. A concrete mixture based on M300 cement is being prepared. If possible, it is better to use ready-made dry mixtures from the manufacturer. As reinforcement, so as not to weigh down the concrete floor slab, microfiber is used, which is added to the solution during mixing.
8. The concrete screed is being poured. To do this, the mixture is supplied in portions starting from the center of the roof. A steel or wooden rule is used for distribution. During work, the screed is checked by level to ensure that the required slope is maintained.
9. After pouring and spreading, the concrete screed is covered with polyethylene. In this condition, the roof surface must be moistened with water 2-3 times a day for 7 days. The complete drying time of the concrete layer is 28 days.
10. After 2 weeks from the moment of pouring, the linear guides can be dismantled. The resulting voids are cleaned and rubbed over with a concrete mixture of similar composition.

    
    Laying a roll or membrane covering is carried out only after the concrete screed has completely dried

11. After the screed has dried, the surface is cleaned of abrasive particles. After this, a vapor barrier diffusion membrane is laid. The vapor barrier is laid with an overlap of 10–15 cm relative to the adjacent row.
12. Thermal insulation material is laid in the form of mineral or basalt slabs. If you plan to install a serviceable roof, it is recommended to lay wool in slabs with a density of at least 50 kg/m3.

    
    Insulation made of mineral or basalt wool is laid on the concrete screed

13. Thermal insulation boards are laid end to end. If necessary, the second layer is laid staggered so that the joints of the first layer do not coincide with the joints of the second.
14. A thin-layer concrete screed (3–4 cm) with fiberglass is poured. The preparation and pouring technology was described above (see paragraph 8). After the second layer of concrete screed has dried, they begin laying the roofing.
15. 2–3 layers of lining roll material are laid. To do this, the canvas is carefully rolled out as the working surface is heated using a propane or gasoline torch.

    
    A gas or gasoline burner is used to lay the fused roofing covering.

16. The roofing material, like the lining material, is installed in a staggered manner with an overlap on the sides of the roof. If a roll coating is used, which is laid on mastic, then the surface is first lubricated with a primer, and only then the material is laid.

At the final stage, roof aerators, gutters, junctions, cornices and other accessories and devices are installed.

It is worth keeping in mind that major repairs of a flat roof in each case may have certain features. This is largely due to the operational condition of the roof, previously laid waterproofing material, etc. But in general, any major repair consists of dismantling work, cleaning and preparing the old surface, laying underlying and roofing material.

Video: laying roofing on a flat roof

Flat roof storm drain repair

The drainage system of a private or apartment building is designed and calculated long before the construction of the house. When constructing private buildings (garages, one-story houses), as a rule, external organized drainage is used. During the construction of multi-apartment high-rise buildings, internal drainage is designed and constructed.

Before repairing the roof of private buildings, it is recommended to perform preliminary dismantling of the storm drainage system. After repairs, the storm drain is reinstalled. If repairs are required, then during installation, damaged funnels, gutters, brackets and other products are replaced with new ones.

The roof funnel is installed during the installation of the roofing pie

Repair of the internal storm drain is carried out in the following sequence:

1. The internal channel is cleaned using a flexible cable with a nozzle in the form of a metal brush.
2. At the stage of installing linear guides for the screed, a slope is formed towards the technological hole in the roof structure.
3. After the concrete screed has dried, a roof funnel is installed in the technological hole on the cement mortar.
4. After the installation solution has dried, the surface near the funnel is treated with a bitumen primer.
5. Next, roll waterproofing is laid in 2 layers. After this, the crimp ring is mounted and a hole is cut in the funnel.

Features of flat roof repair in winter

Routine and major repairs of flat roofs in winter are carried out only in exceptional cases when repair work is necessary to maintain the integrity of the ceiling.

Laying roll coverings in winter should be carried out with extreme caution.

When carrying out work in winter, you must adhere to the following rules:

• It is advisable to carry out repair work on a clear day - this will avoid problems when laying roofing material;
• when laying materials, moisture should not be allowed to get between the different layers of the roofing cake;
• If the winter is snowy, then frame-tent shelters are used for repairs, which help prevent precipitation from getting on the roof surface.

To ensure thermal conditions, gasoline or gas heat guns are used. The roofing material must be kept at room temperature for 24–36 hours.

How much does it cost to repair a flat roof?

Flat roof repairs are complex work, so their final cost consists of the cost of the material, the cost of its delivery, labor costs, etc. At the same time, the cost of a major repair is difficult to estimate without a preliminary inspection of the flat roof.

On average, the cost of current repairs, which you can do yourself, will cost no more than 200 rubles/m2. The total costs mainly consist of the cost of the material and the rental of tools if they are not available. Major work costs approximately 2–2.5 times more than local repairs of minor damage. If repairs are carried out with the involvement of specialists, then the final cost increases by about 2 times.

To estimate the cost of repairing a flat roof, you can use the table below. The data in the table is compiled based on price lists from three specialized companies performing repairs in the central region of Russia.

Table: Cost of Repairing an Existing Flat Roof

Name of works	Unit change	Price (work + materials), rub./m2	Price (work only), rub./m2
Repair of an existing flat roof made of fused materials
Roof repair in 1 layer, including repair of old roofing carpet (opening and gluing of swellings and other defective places)	m 2	500	350
Roof repair in 2 layers, including repair of old roofing carpet (opening and gluing of swellings and other defective places)	m 2	800	530
Roof repair in 2 layers, including complete removal of the old roofing carpet and screed repair	m 2	900	560
Installation of a flat roof during capital construction and repairs
Installation of roof covering in 2 layers on the finished base	m 2	750	430
Installation of a new lightweight roof (vapor barrier, 150 mm mineral wool insulation, 2 layers of fused material)	m 2	1700	570
Installation of a new roof (vapor barrier, 150 mm mineral wool insulation, reinforced cement-sand screed, 2 layers of fused material)	m 2	2400	800
Installation of a new roof with a screed and slope (vapor barrier, mineral wool insulation 150 mm, expanded clay slope with an average thickness of 100 mm, reinforced cement-sand screed, 2 layers of fused material)	m 2	2700	910
Repair of existing flat roof made of polymer membranes
Repair of an old roof using a PVC membrane covering (removing bubbles on the old carpet, laying geotextiles, installing a 1.2 mm membrane covering)	m 2	850	350
Installation of a roofing carpet made of PVC membrane on a finished base with mechanical fastening	m 2	750	250
Installation of a new lightweight roof (vapor barrier, insulation with 150 mm thick mineral wool slabs, installation of a roofing carpet made of 1.2 mm PVC membrane)	m 2	1750	420
Installation of a new roof with a screed and slope (vapor barrier, insulation with mineral wool slabs 150 mm thick, expanded clay slope, cement-sand screed up to 50 mm thick, installation of a roofing carpet made of 1.2 mm PVC membrane)	m 2	3000	1000

Major roof repairs are expensive work, the quality of which determines the comfort and coziness inside the living quarters of the house. Therefore, when constructing a house, you should perform all the work efficiently and not skimp on materials. In order not to bring the roof to a critical condition, it is recommended to carry out routine inspections and local repairs, if the need arises.

Flat roofing is superior to pitched roofing in cost and ease of installation. But there is also a drawback: relatively often you have to do repairs. How and with what materials it is carried out - these questions will be the topic of this article.

Types of flat roof repairs

Roof restoration work is usually divided into three categories:

1. Maintenance.
2. Major renovation.
3. Emergency measures.

Maintenance

Current repairs are a set of works aimed at maintaining the normal condition of the roof: minor damage and defects that may lead to leaks in the future are eliminated. Typically, the total area of ​​the areas being restored does not exceed 40% of the total roof area, and repairers most often limit themselves to manipulating the surface layer.

Problem areas are identified through an inspection, which is recommended to be carried out once every six months, or at least once a year.

It is very important to carry out routine repairs in a timely manner, since minor damage on a flat roof quickly develops into large ones, which entails a significant increase in the cost of restoring the coating.

Major renovation

In case of severe wear and tear, when the area of ​​areas with damage or unsatisfactory condition exceeds 40% of the roof area, a full-scale reconstruction of the roofing pie is resorted to. In fact, the roof, starting with the vapor barrier, is laid anew - only a small part of the materials that are in good condition is reused.

When performing a major overhaul of a flat roof, all layers of the roofing pie are dismantled and re-laid

Emergency repairs

Emergency repairs must be resorted to urgently if the roof leaks. If current and major repairs are usually carried out in the warm season, then emergency repairs are done when necessary, and this is its peculiarity.

In winter, emergency work is carried out to urgently eliminate roofing defects.

As part of emergency repairs, as well as current repairs, only the surface layer is usually manipulated. In most cases, the area of ​​damaged areas does not exceed 20% of the entire roof area, but if necessary, the coating is replaced in larger quantities.

Preparation for repair

During roof repair work, it is often necessary to dismantle the old roofing covering. It is clear that at this moment the structure in some places loses its protection from precipitation, so you need to prepare very carefully so that nothing prevents the repairs from being carried out as soon as possible.

Selection of materials for repairing flat roofs

For the device and, accordingly, four types of materials are used.

Bitumen coatings

The category of bituminous materials includes traditional roofing felt, which is cardboard coated with bitumen, as well as newer coatings such as metalloizol and folgoizol, which are reinforced with foil.

Folgoizol is a multilayer structure with an outer coating of aluminum foil

Bitumen waterproofing is the cheapest, but also the least durable - the material becomes unusable after 5–7 years. Such a short service life is explained by the following disadvantages:

• low frost resistance - moisture is retained in the pores of bitumen, which gradually destroys the material during successive freeze-thaw cycles;
• insufficient ductility - due to temperature changes, the bitumen coating cracks relatively quickly;
• instability to ultraviolet radiation (bitumen materials and mastics used for gluing them become even more fragile under sunlight).

Bitumen-polymer materials

Adding a small amount (usually no more than 12%) of various polymers to bitumen makes it possible to increase the frost resistance of the material and its plasticity, as a result of which the service life is extended to 15–20 years. In addition, instead of fragile cardboard, fiberglass, fiberglass or polyester is used as a base, due to which the material acquires increased resistance to mechanical stress.

Rubemast is manufactured using more modern technology than roofing felt, therefore it has a service life several times longer

Currently, a wide range of materials are produced using this technology, for example, bikrost, rubemast, rubestek, hydrostekloizol, steklomast, steklobit, linokrom.

Particular success has been achieved by mixing crumb rubber, elastomers, thermoplastic elastomers and thermoplastics into bitumen. Materials made in this way are produced under the brands Filizol, Thermoflex, Dneproflex and Dnepromast, Luberite, Elabit, Mastoplast, Isoplast, etc.

People often call bitumen-polymer materials Euroroofing felt. In addition to increased resistance to negative factors, it has another important difference from roofing felt: laying can be done by fusing, for which the lower surface is heated with a gas or gasoline burner.

To fix the euroroofing material, it is enough to heat its bottom layer using a burner - gasoline or gas

At the same time, euroroofing felt also inherited some disadvantages from its prototype: it also has to be laid in several layers, and, with rare exceptions, it is necessary to sprinkle the surface with stone chips.

The cost of bitumen-polymer materials is higher than traditional roofing felt, but due to the less frequent repair work, the cost of maintaining the roof is ultimately reduced by 2 times (based on 40-year operation).

Single layer membranes

Single-layer membranes are a fundamentally different type of coating, which is made from synthetic rubber or polymers. It has a number of advantages:

• laid in one layer, so it can be installed very quickly;
• is very elastic;
• has no pores, therefore it has high frost resistance;
• perfectly resists all other negative environmental factors - UV radiation, oxidation and temperature changes;
• can be installed at any time of the year;
• does not require powdering with stone chips;
• supplied in rolls up to 15 m wide (the width of bituminous materials is 1 m), due to which the number of seams on the roof is significantly reduced.

The membrane can be secured either with glue or bitumen mastic, or with self-tapping screws. Thanks to the long service life (more than 25 years), single-layer installation and the rare need for repair work, you will have to spend 4 times less money on maintaining the roof over 40 years of operation than in the case of a bitumen roof.

Roof repairs using the single-layer Ecoplast membrane can be carried out at any time of the year

The production of membranes in Russia has been mastered for quite a long time: Cromel, Ecoplast, Logicbase, Rukril and others membranes have proven themselves well.

Roofing mastics

Roofing mastics are liquid compounds that are applied to the roof in any of the following ways:

• spraying (industrial sprayers are used);
• using a brush;
• using the pouring method followed by leveling with a roller.

After some time, the mass polymerizes and turns into an elastic, waterproof film, similar to rubber. Because of this similarity, roofing mastics are often called liquid rubber. The film is extremely elastic - it does not tear at a relative elongation of up to 1000%. This means that when the building shrinks, the roofing will remain intact.

After polymerization, roofing mastic turns into a waterproof film similar to rubber

Compared to rolled materials, mastics have an important advantage: the coating will be seamless for any roof area. They are also very useful for repair work, as they allow you to fill the most difficult to reach cavities.

Roofing mastics are produced in both one-component and two-component versions. In the second case, the base composition must be mixed with a hardener.

The composition of mastics varies quite a lot, and accordingly, their service life is different:

• butyl rubber, for example, “Germabutyl NMG-S”, “TechnoNIKOL No. 45”, “Polikrov M-120/M-140” serve for 25 years;
• chlorosulfopolyethylene, for example, “Polikrov-L”, “Izokrov”, “Krovlelit” also protect the roof surface for up to 25 years;
• bitumen-latex, for example, TechnoNIKOL No. 33, BLEM 20, Master Flex must be updated every 20 years;
• bitumen rubber, for example, REBAKS-M, MGH-K, Venta U, will require repair after 15 years of operation.

To glue rolled materials you will need bitumen mastic (not to be confused with roofing mastic - “liquid rubber”). You can buy it at the store, or you can make it yourself. There are two varieties of this material:

• cold mastic - used for gluing the internal (lining) layers of rolled material;
• hot mastic - applied over the coating as a protective layer and to fix the stone chips.

Cold mastic is prepared from the following ingredients:

• bitumen - 2 parts;
• gasoline - 2 parts;
• filler, which can be used as gypsum, lime or ash powder - 1 part.

The bitumen is heated in some container and kept for some time so that the moisture completely evaporates from it. The temperature at which evaporation is carried out is approximately 180 o C. Then filler is poured into the bitumen, after which the mixture is thoroughly stirred with a wooden stick. Next, you need to pour it into gasoline.

If the bitumen is heated, then it is this that needs to be poured into gasoline, and not vice versa. Otherwise, a fire may occur. After cooling, the mastic can be used for its intended purpose. It should be borne in mind that it is not stored for a long time, so there is no point in preparing a large volume for the future.

The technology for preparing hot bitumen mastic involves cooking bitumen at a temperature of approximately 200 o C. During this process, filler is gradually added, while the bitumen is mixed.

If a small amount of bitumen is needed for repairs, it can be heated in a metal bucket, and for large volumes special installations are used

If, when mixing bitumen with filler, the temperature of the mixture drops below 160 o C, the material will greatly lose quality.

To insulate the roof, you should use a material that can support the weight of the coating and snow without being greatly deformed. These are:

• extruded polystyrene foam. Its composition is identical to regular polystyrene foam, only the structure is homogeneous and not granular;
• rigid slabs made of mineral wool. The density of the material (varies from 50 to 400 kg/m3) must be selected in accordance with the snow loads characteristic of a given region;
• expanded clay The cheapest, but at the same time the least effective heat insulator.

Video: repairing soft roll roofing using mastic - what you need to know

Budgeting

For large volumes of work, it is useful to calculate the necessary materials and calculate their cost. Having an estimate in hand, the owner of the building is guaranteed to acquire everything he needs, so that during repairs he will not have to be distracted by secondary actions. In addition, the estimate will show what funds will need to be allocated, because with large-scale repairs the costs can be quite significant.

If it is decided to entrust the repair of the roof to a team of hired workers or a specialized company, then to draw up an estimate they need to provide the following information:

Preparing tools

To carry out the work you will need:

1. Assembly cutter. With its help it is convenient to remove worn roofing coverings. This tool can be replaced with a well-sharpened ax, which, instead of an axe, is attached to a handle made of a steel pipe of suitable length.
2. Construction knife. Used for cutting sheets of roofing material.
3. Gas or gasoline burner (blowtorch). It is used for fusing bitumen-polymer roll material, if it is decided to use it as a roofing covering. It is easier to work with a gas burner, and the fuel for it is cheaper. But it is also more dangerous, so in the absence of skills it is better to use a blowtorch.

   The use of a gas burner requires the roofer to pay increased attention to safety rules

4. Construction hairdryer. Helps quickly dry the area being repaired, and can also be used for fusing some materials.

   Using a construction hair dryer, you can quickly dry the area being repaired or fuse roofing material.

5. Maklovitsy. This is the name given to special brushes that are used to apply mastic and primer during roofing work. If there are no brushes available, you can use an old broom instead.

   Apply primers and mastics with a wide brush - a paintbrush.

6. Roller. Used for leveling mastics.
7. Protective glasses. According to safety requirements, glasses must be worn when working with a gas burner, as well as when knocking down screeds.

Flat roof repair technology

Each type of defect on flat roofs is eliminated using its own method.

The roll material has peeled off

The sequence of actions is as follows:

There is a crack or bulge in the coating

The easiest way to repair such damage is to install a patch. Before this, you need to determine how deeply the moisture has penetrated into the roofing pie.

1. The area with the crack is cut out with an ax or a mounting cutter, and the swelling is opened with a cross-shaped incision. If the underlying layer of roll material is wet, it needs to be cut out. Do the same with other wet layers until they reach dry.

   The area with a crack or swelling is opened using a cross-shaped incision

2. In the resulting hole, place one on top of the other as many fragments of rolled material as were cut out, gluing each one with mastic.
3. If the defect was a swelling, then 4 triangular valves, bent after opening, are returned to their place and securely glued with mastic. Some craftsmen nail these flaps with slate nails.
4. The roof area within a radius of 10–15 cm from the damage site is cleared of debris, dust and dirt, and the cleaned area is filled with bitumen mastic.
5. Apply a patch of the appropriate size.

   A layer of mastic is applied to the opened and treated area, and then a patch is laid on it, the edges of which are also coated with bitumen

6. The edges of the patch are coated with mastic and sprinkled with stone chips, pressing them into the bitumen using a roller.

Installing a patch is not always guaranteed to provide the desired result. The repairman may not notice hidden damage, so after repair the roof will still leak. They often make the mistake of installing a patch above the place where the water appeared on the ceiling: in fact, the damage can be located up to 2 m from the leak.

Taking into account all that has been said, many craftsmen prefer to simply lay a new one over the worn-out coating, which is commonly called repair the old way. It must be taken into account that laying new layers one after another significantly increases the load on the walls. For safety reasons, it is not allowed to lay more than eight layers of coating on the roof, but even with fewer layers, it is advisable to perform strength calculations of the walls and ceilings.

Video: technology for repairing cracks and blisters on a flat roof

Roofing membrane damaged

Single-layer membranes, which were described above, withstand atmospheric influences, but can be damaged, for example, when removing snow from the roof with a metal shovel. The tightness of such a coating is restored as follows:

If peeling occurs in the seam area, then the peeled area is welded in the same way, having previously treated it on the inside with a solvent. If the broken section is more than 5 m long, it should be restored using a special repair tape, for example, Eternbond.

Cracks have appeared in the mastic roofing covering

Cracks in the mastic coating appear as a result of aging of the material. Restoration is carried out with the same mastic from which this coating was made. They work like this:

In case of extensive damage, the repair layer must be reinforced with fiberglass mesh with a density of 100 g/m2. First, a layer of mastic is applied by spray, then the mesh is laid, and after that the mastic is applied again, which should completely hide the mesh.

Stages of flat roof repair

Any repair begins with an inspection of the roof. Here's what you need to pay attention to:

Particular attention should be paid to checking areas adjacent to pipes, parapets, ventilation shafts and other objects on the roof.

If the damage covers more than 40% of the roof, a major repair is performed, which includes the following steps:

1. Removal of existing roofing material.
2. Dismantling the screed (bumpers or special machines that cut grooves in the screed can be used).

   Major repairs to a flat roof begin with the complete removal of the old roof covering and the concrete screed underneath

3. Removing insulation.
4. Replacing the vapor barrier or, if possible, restoring it.
5. Restoration of elements of the internal drainage system.
6. Installation of insulation. If mineral wool slabs are used for this purpose, you can purchase varieties that have the slope necessary to ensure drainage (they are called wedge-shaped).

   When using wedge-shaped thermal insulation material, the slope of the roof can be done already at the stage of its insulation

7. Sloping the surface by adding sand or expanded clay (if the slope was not formed by insulation).

   The slope of a flat roof can be done by pouring a layer of expanded clay on top of the insulation

8. Installation of funnels for water drainage (elements of the internal drainage system).
9. Laying a screed from a cement-sand mortar and then covering it with bitumen (prevents moisture evaporation).

   Before pouring the screed, reinforcement mesh and wooden beacons are installed on the roof surface

10. Laying roofing material. Bitumen and bitumen-polymer roll materials should be laid in 3–5 layers (the lower the roof slope, the more layers). The strips are laid with an overlap of 10 cm or more, gluing them with mastic. In the first layer they are laid parallel to the cornice, in the second - perpendicular, while the ends of the strips of the second layer are placed on the walls and glued or fixed with dowels. Next, the direction of the stripes in the layers must be alternated.

It is not always possible to perform the tilt correctly. To identify errors, perform the following test:

• before installing the last layer of coating, the roof is filled with water;
• Mark with chalk those areas from which moisture does not drain.

After drying such dents, you need to pour a thick layer of mastic or glue a piece of rolled material (no thicker than 1 mm), after which you can lay the finishing layer with stone powder. If there is no powder (ordinary roofing felt), it is applied independently onto a layer of hot mastic, into which the stone chips are pressed with a roller.

Video: flat roof repair on the roof of a house

To reduce the frequency of flat roof repairs, you must initially rely on high-quality materials. And during maintenance, you should protect the coating from mechanical damage - when clearing the surface of snow and ice, it is not recommended to use a metal shovel or crowbar.

We are pleased to welcome you to the website of the roofing company "Stroy-Alliance"
The main and priority activity of our organization is the high-quality performance of work on the installation and repair of flat roofs. We will reliably carry out the following work:

	Laying of laying and built-up vapor barrier.
	Each type of these plates has its own advantages and disadvantages. Call and we will offer the brand of insulation that is suitable specifically for your case.
	We will carry out work on creating slopes from expanded clay or using wedge-shaped thermal insulation.
	Installation of cement-sand and prefabricated screeds.
	Reliable brands of roofing waterproofing. No fiberglass as a base for rolls. Only fiberglass and polyester. Traditional technology for repairing soft flat roofs involves fusing roofing roll materials using gas burners. This method of installing and repairing flat roofs is intuitive and has been used for over 30 years. The practical experience of performing such work by specialists of our organization is 17 years. For roofing we use high-quality materials from TechnoNikol.
	Polymer-bitumen grades with a thickness of more than 6 mm (with two-layer laying) The service life of the roll coating is from 15 years. Strict adherence to work technology.
	Domestic and imported polymer membranes. All components for installation are available. Three automatic welding machines. Teams with 10 years of experience in installing roofs using PVC membranes.
	Prompt visit to the site. Reliable defect removal. Roofers of the Stroy-Alliance company are certified by TechnoNikol.
	We will draw up a commercial offer based on the technical specifications or defective statement within 1 working day. If necessary, we will calculate the cost according to government rates.

In our activities we use only proven technologies and use materials that have passed many years of testing under real operating conditions. As a matter of principle, we do not work with materials that have low technical performance and a short service life. We deliver basic materials to the site directly from manufacturing plants, bypassing intermediaries.
We offer potential Customers various methods of performing work. This also applies to the optimization of grades of materials and technologies used in the installation of roofing structures. We know how you can save without losing quality!

Do you want the repair or installation of flat roll roofing to be carried out with high quality, without violations of technology and in a short time?
Call now or leave a request and our roofers will get to work!

Advantages of cooperation with the Stroy-Alliance company

The Stroy-Alliance company is proud of its team. Due to the fact that we have no “staff turnover”, over the years of our existence, the company’s employees have acquired invaluable experience and trained in Russian and foreign companies. All this guarantees that our specialists will prevent errors, take into account every nuance in the work and ultimately provide a high-quality product. Stroy-Alliance specialists strictly fulfill their obligations under the contract, so our company is considered a reliable partner. Expensive modern equipment that we use for installation and repair of flat, soft, built-up, bitumen roofing, laying roll roofing, roof waterproofing is an advantage of Stroy-Alliance, as it allows us to minimize work time without loss of quality.

• We have more than ten years of experience working with PVC membranes. We provide our services at a wide variety of facilities: shopping malls, warehouse terminals, private homes;
• We install membrane roofing in the shortest possible time (from 500 square meters per day);
• Quick preparation of estimates, preparation of a full package of documents when putting the facility into use (acts of acceptance of completed work, acts of hidden work, etc.);
• We carry out installation of roll roofing made of PVC membranes, repairs, and installation of fused flat roofing throughout the Central Federal District of Russia;
• The work of the Stroy-Alliance company fully complies with tax legislation (VAT is deducted when concluding a contract);
• Installation and repair of flat roofs is carried out using a variety of methods (modern and traditional);
• The visit of a technical specialist is carried out with maximum efficiency and completely free of charge;
• The brands of materials used are agreed upon with the Customer;
• When providing services, we use the latest foreign equipment;
• Citizens of the Russian Federation work in the brigade.

Place your roof repair worries on the shoulders of our specialists!

Arrangement and repair of flat roofs is done by two types of materials: soft or self-leveling. They provide excellent sealing of roofing layers, protection of the house from damaging environmental influences and a long service life. There are typical damage to roofs made of soft materials that occur periodically regardless of the quality of the materials used.

Types of damage

You can find out whether there is a need for roof reconstruction by carefully examining its surface. You can detect defects in the roof of a house if you simply walk on it. Damaged areas may crunch, sag, and swell.

Roof Condition Assessment

Types of flat roof damage:

• separation of the “pie”: complete or partial;
• swelling of the coating;
• the appearance of bubbles;
• the appearance of cracks;
• the formation of depressions and funnels filled with rainwater;
• peeling of the coating around chimney pipes;
• germination of all kinds of vegetation inside the coating layers.

If you periodically carry out a preventive inspection of the roof of your house for defects, then minor routine repairs to the surface can be done with your own hands. But if this is not done in time, the defects will gradually progress and the roof may begin to leak. In this case, it may be necessary not only to overhaul the roof of the house, but also to restore the interior decoration of the room.

Roofing defect

Consequences of untimely roof repairs:

• the growth of moss and other vegetation;
• the appearance of mold;
• deformation of wooden walls and floors of the house;
• violation of interior decoration;
• occurrence of leaks;
• icing of house walls and ceilings in winter;
• the appearance of multiple cracks,
• peeling of finishing materials, accelerated destruction due to rotting.

Deformed covering area

• in early autumn, so that there are no problems with a leaking roof;
• in the spring, after the snow melts - to eliminate damage after winter;
• in summer it is necessary to remove leaves and clear the roof of moss;
• In winter, you need to clear the snow on time.

This will help reduce the cost of ongoing home repairs.

How to repair a flat roof

Depending on the size and nature of surface defects, two types of repair can be noted:

• small current;
• capital.

Partial replacement of roofing

There are two effective methods for repairing a flat roof.:

• sticking to mastic;
• fusing using high temperature exposure.

Membrane roof installation

PVC membranes are a soft material for roof repairs, with which you can carry out repairs easily and quickly. The big advantage of such coatings is that installation can be done in one layer directly on the previous roofing felt coating. The only requirement is that the surface must be clean (no stones, debris, old grease stains, or puddles of water).

Membrane roof structure

To carry out the work you will need:

Work technology

The rolls are rolled out on the roof surface and the required pieces of sheets are cut off. The canvases are overlapped by 12 cm. The edges of the canvases are fixed with dowel nails every 40 cm. The edges are connected with heated air from a welding machine. In this case, a stream of hot air is directed under the canvas and immediately rolled with a roller. This method is justified when repairing large areas.

Application of euroroofing felt

This repair technology is much more economical, but the surface must be perfectly clean. The material is laid in two layers. The first is the main one, and the second is decorative. Thanks to a special powder, decorative roofing felt is not afraid of the sun, frost, does not crack or dry out, is chemical-resistant and has a long service life (about 30 years). The material is produced in rolls.

Deposition of material

Materials and tools for work:

1. Two types of euroroofing felt;
2. Gas-burner;
3. Special scissors;
4. Hook.

Fused technology

Strips of the required length are measured and rolled again for convenience. Each canvas is heated using a gas burner and rolled out, holding it so as not to get burned with an iron hook.. In this case, the material is firmly attached to the surface. A decorative layer is placed on top of the bottom layer using the same algorithm. The two layers are then melted simultaneously, ensuring a secure adhesion and long-lasting coating.

other methods

Minor repairs to the soft roof of a house can be done using ordinary roofing felt. It, of course, does not have all the advantages of modern analogues, but in case of minor roof defects, you can use pieces of roofing felt, laying them on molten bitumen. The material can even be laid on top of iron or slate surfaces.

Elimination of minor defects

For small cracks in the slate plane, scraps of fabric in oil paint will help - they can repair minor damage.

Large fragments of damage must be replaced or the roof completely covered with new material.

How to correctly calculate reconstruction costs

The technology for carrying out minor routine repairs does not require such preparations; it can be carried out spontaneously without any preliminary preparation.

When planning a major roof repair, it would be quite reasonable to make a preliminary calculation of the costs of repairing a roof made from roll materials.

You must first calculate the material consumption

Procedure for planning repairs:

1. Carrying out measurements of the territory within which it is planned to replace the coating.

2. Compiling a list of all required materials, taking into account the nature of the defects.

3. Adding to the list of materials for the production of cement-sand mortars if it is planned to update such areas of the roof.

4. Add 10-20% excess consumption of materials to the result obtained.

5. Consider offers from various building materials stores, take note of promotions and conditions for delivery of materials.

Major renovation

Major roof repairs require large expenses and a lot of time, but the procedure itself can be done with your own hands, provided you have some skills.

Complete replacement of old coating

Event technology:

1. Dismantle the roofing pie and check the condition of all insulating layers.
2. If damaged coatings are identified, the entire area should be replaced.
3. Make a cement-sand screed, following the instructions on the mixture packaging.
4. Pour the solution in a layer of 2-4 cm and wait for the surface to dry.
5. Prime with bitumen emulsion.
6. Treat the entire roof area with mastic.
7. Lay the pre-heated parts of the solid sheet on the roof surface, pressing with a stick. The procedure is easier to do with two people.
8. Lay all the strips overlapping, maintaining 15-20 cm of overlap.
9. Seal seams, joints and hard-to-reach places.
10. If desired, you can make an additional layer of soft roofing by rolling out the roll in a perpendicular direction.

In order for a major roof repair to produce results and save you from carrying out such events for the next ten years, you must follow all the rules when laying the covering. You should also take into account the fact that the condition of the coating will depend on the quality of the selected material. It is better to choose products from reputable manufacturers.