Fastening PVC membrane to the roof. Membrane roofing: installation technology. Ballast fastening of membranes to the base
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Membrane roofing is the most modern look roofing. Its popularity is due to its excellent technological properties and long service life. finishing coating. Due to its increased strength, resistance to moisture and excellent adhesion to all bitumen-based materials, this roofing is widely used in individual construction.
Usage polymer materials and artificial rubber, which are flexible and elastic, allow you to create roofing coverings on roofs of any plane and different slopes. Device technology membrane roofing most often allows the wonderful qualities of these materials to be used on slightly inclined and flat roofs Oh.
Today, different types of roofing membranes are produced. Let's focus on the three main ones.
PVC membrane. This coating has an excellent structure. It is based on artificial material polyvinyl chloride, which has long been used in the production of insulating, finishing and other building materials.
PVC membrane To increase the elasticity of the fabrics, volatile plasticizers are added to the material composition. Thanks to the polyester reinforcing mesh, it gains additional flexibility and elasticity. These properties remain indispensable when laying membranes on roofs with complex configurations.
If we make a comparison, the PVC roofing membrane is the most practical and cheapest in relation to other types of rolled polymer roofing coverings. Therefore, at the moment they are the most popular and in demand.
The advantages that distinguish this material from conventional roofing coverings include the absence of unwanted leaks that arise due to the characteristics various materials, used for roofing.
As a rule, the joints of the canvases do not fit tightly enough to each other, which is why moisture from the atmosphere gradually penetrates into interior spaces buildings Unlike other coverings, PVC membrane roofing has virtually no seams. As a result, leaks on such a roof are minimized.
Among the advantages of installing this type of roof is the saving of labor and material resources. It does not require creating a technological layer of gravel, which is usually done when installing a roof from traditional rolled materials.
Another advantage that PVC membrane roofing has is its color. It is light, and therefore the roof reflects most of the light falling on it. sun rays. In the current heat this is a tangible advantage.
EPDM membrane. The basis of this material artificial rubber is used - ethylene propylene dienomonomer. The polymer mesh used to reinforce the material gives it increased strength properties. This construction material has a very long service life.
To increase the strength of the roof covering, EPDM membranes include additives - polyester and modifying ones. The membranes have excellent adhesive properties (adhesion) in relation to materials based on bitumen. All this speaks of the remarkable waterproofing properties that membrane roofing has.
The cost of EPDM membranes for roofing is not cheap. But if you break down the price by the service life of the roofing (more than 50 years), then it is unlikely that it will seem so high and unjustified.
TPO membrane. These membranes came to the Russian roofing waterproofing market relatively recently. This roll coating includes several types of thermoplastic olefins.
Various manufacturers They form the composition of the products they produce according to the individual membrane formula and the ratio of polypropylene to ethylene-propylene rubbers. More common is membrane roofing, the technology of which provides for a ratio of 30% to 70%.
To increase strength and fire resistance during the production of this modern material, antioxidants and various stabilizing substances are added to its composition.
If we talk about the similarity of thermoplastic membrane roofs with their thermosetting analogues, then they are based on a completely different material - not rubber, but polyvinyl chloride or similar polymers.
Although PVC sheets are not joined by heating, their seal is so tight that they do not allow water to easily pass through the seams. Moreover, such materials for finishing the roof are more affordable (when compared with thermosetting analogues). The only downside is that they require constant Maintenance and more frequent membrane roof repairs.
There are two types of TPO membranes on the market today. One is reinforced with polyester, and the second is unreinforced, consisting of fiberglass.
TechnoNikol superdiffusion membranes are of especially high quality. These three-layer microporous membranes have a top and bottom layer made of non-woven polypropylene. In the middle of such a durable frame is the so-called “working layer”. It consists of a polypropylene film that has unique properties due to which steam diffusion occurs and, at the same time, creates a barrier to the passage of water.
The middle layer, which contains the TechnoNikol membrane roofing, has excellent relative tensile properties. A frame made of non-woven propylene, which has high strength values, together with the middle layer ensures a balanced material in terms of such indicators as resistance to mechanical loads and damage, excellent vapor permeability and water resistance. The layers in a superdiffuse membrane are connected using ultrasound, which guarantees high stability of the material characteristics and eliminates the possibility of damage to the “working” middle layer. This type of membrane roofing is safe and is not affected by bacteria. The film is formed into rolls measuring 1.5 m by 0.5 m.
Advantages of roofing membranes
The use of roofing membranes helps to achieve excellent waterproofing and heat-insulating properties of the finishing coating. Conveniently, membranes can be laid on any type of base. The obvious and indisputable advantages of the material laying process is the rapid implementation installation work.
Membrane roofing is an ideal covering for low-slope and flat roofs. This does not mean that it cannot be installed on roofs with complex geometry.
By repairing the roof using membrane materials, there is no need to dismantle the old damaged roofing covering. It’s hard not to agree that this situation will significantly reduce labor costs and reduce the cost construction work.
The main thing that includes repairing a membrane roof is cleaning the base of the roof from debris. After this, geotextile fabric is spread in two layers. It is designed to protect the coating from damage. Then the roof is sealed in strict accordance with the technology of roofing work.
Polymer membrane materials have undeniable advantages, for example, they
- exhibit thermal stability in relation to daily and seasonal temperature changes;
- have high elasticity, ductility and tensile strength;
- provide a minimum number of joints;
- can be used on roofs with complex and non-standard configurations;
- The installation of a membrane roof can be carried out in the shortest possible time.
Since the roofing membrane has high quality indicators, modern construction successfully uses this popular material.
Installation of roofing membranes
The thermosetting type sheet is attached to the base of the roof mechanically, after which using special equipment The joints are heated with hot air. Then the canvases are welded to each other in an overlapping manner.
Membrane roof repair reliably fixes the membrane sheet to the roof, while ensuring the highest level of waterproofing of the entire finishing coating.
Due to the fact that the membrane panels do not fit very tightly to the base, excellent ventilation is ensured between the two layers of the roof. Since the resulting condensate does not settle, there is no need for a waterproofing under-roof membrane.
In places where the finishing coating adjoins other roof elements (podiums, corner seams, parapets), a heat gun is used for its installation. Such simple equipment for membrane roofing is also used in hard-to-reach places for processing joints.
You need to be careful and do everything correctly technological operations for membrane installation. If work is carried out with violations, the consequences can be very bad, for example, depressurization of joints may occur.
If work is carried out on industrial, warehouse buildings and structures made of metal structures, when the base for the coating is corrugated sheets, before covering the roof with membranes, a rubber-bitumen emulsion or rubber-based mastic is applied to them. With this approach, the membrane roof receives additional waterproofing.
Membrane mounting and mounting options can be as follows:
- The roof area is filled with a ballast layer of crushed stone, gravel and other materials.
- The covering is mechanically fixed to the base of the roof using “racks”.
- The roofing membrane is attached using adhesives.
Thermoplastic membrane roofing is installed differently than its thermoset counterpart.
Sequence of installation work
The membrane roofing you make yourself will reliably protect your roof and will last for 20-30 years. This type of coating does not require additional waterproofing, since it itself perfectly resists moisture.
Compared to conventional roll materials, membrane roofing can be installed in the shortest possible time.
Repairing a roof using this type of coating requires certain knowledge and ability to operate welding equipment. If you are not confident in your own skills, it is better to entrust the work to professional craftsmen.
Membrane roofing is one of the most modern and popular types of roof coverings. Its demand is explained by excellent technical parameters: increased strength, moisture resistance and good adhesion, which makes this material indispensable for many in private construction.
Membrane roofing - what is it?
Membrane roofing is a film made of polymers 0.15-0.20 cm thick, reinforced with fiberglass. Weight 1 sq.m. material is no more than 1.5 kg.
Each manufacturer adds a variety of plasticizers to the primary material; this can be fiberglass or converted bitumen. The main component of the raw material can also be different.
Typically used for the production of membranes:
- PVC– polyvinyl chloride is the most common type of membrane.
- EPDM– ethylene propylene diene monomer or synthetic rubber.
- – thermoplastic polyolefin, consists of 70% ethylene-propylene rubber and 30% polypropylene.
These bases can be supplemented with reinforcement - a polyester mesh, which gives the material additional strength.
The membrane coating is flexible and elastic, so it can be used on roofs with any angle of inclination and plane. It is also worth noting that membrane roofs are fire-resistant, have a long service life and can withstand loads if the roof is used for other purposes.
Types of roofing, their features
The membrane roofing system is available in three types:
1.PVC
The membrane is made from plasticized polyvinyl chloride, widely used in construction and waterproofing. To strengthen the panels, they are reinforced with a polyester mesh. Covering the roof with such material can be done without much effort on the roofs of various geometric shapes without creation additional layers. Membrane fabrics of this type have almost no seams, which virtually eliminates roof leaks.
Compared to other types of roofing membrane coverings, PVC is considered a particularly economical and practical material, but periodically requires repairs. It should also be noted that this roofing system is poorly resistant to resin-like products, solvent mixtures and oils.
2. EPDM
The membrane is made on the basis of synthetic rubber. The material reinforced with a polymer mesh has increased strength, which ensures a long period of operation. This coating adheres well to bitumen-based surfaces, which provides good waterproofing.
EPDM coating is durable (service life is about 50 years), elastic, and also relatively inexpensive. During installation, the joining of the canvases is done using glue, so cracks may form at the joints, which lead to leakage.
The membrane is made on the basis of thermoplastic olefins - polypropylene and ethylene-propylene rubber. The coating can be made with polyester or fiberglass reinforcement, or without reinforcement.
The antioxidant substances included in the material increase its fire resistance. The joining of the sheets is carried out by welding with hot air, which creates a strong seam, as a result of which there is no need for frequent repairs of the coating. The difference between the types of flooring listed above is that this type not so elastic. It should be noted that the price of TPO membranes is quite high.
Polymer roofing has many advantages:
- High degree of thermal and waterproofing (the minimum number of joints reduces the risk of coating leaks, and the multilayer structure of the material retains heat).
- Does not require much effort during installation (laying can be done on various types of bases).
- When repairing a roof with such a coating, dismantling the old decking is not necessary, which significantly reduces labor and money costs.
- High stability to seasonal temperature fluctuations.
- High degree of reliability.
Roof installation
Laying a membrane type of roof does not require specific knowledge and professionalism in this field.
Four technologies are used for its design:
- Ballast method.
- Glue method.
- Heat welding method.
- Mechanical method.
How to install
Regardless of the method of fastening the material, it is necessary to adhere to some mandatory rules when installing the roof:
- Surface preparation - it should be thoroughly cleaned of debris, dust and deposits.
- Calculate the required amount of coverage.
- Use thermal insulation materials, extending the service life of the membrane.
1. Ballast method
The installation method is as follows:
- Distribute the canvas along the length of all sides of the roof, then carefully level it.
- At the joints, the material is connected and secured to the vertical surfaces of the roof with special glue or by hot air welding.
- The attached sheets are sprinkled on top with gravel, crushed stone, medium-fraction river pebbles or broken stones, paving slabs, and the weight of ballast per 1 m2 must be at least 50 kg. To avoid damage to the canvas when using crushed stone or gravel, it is advisable to lay dense non-woven fabric.
2. Glue method
Adhesive fastening of the membrane sheet is intended for covering roofs of complex configurations, as well as in climatic regions where the decking is often exposed to strong gusts of wind. To attach the membranes, use special adhesives or double-sided adhesive tapes, in this case, the material is glued not over its entire surface, but along the length of all sides of the roof, at the junction of the panels.
Mounting adhesive is suitable for installing membrane sheets on reinforced concrete, wooden base, as well as surfaces made of profiled sheets. To strengthen the coating on vertical elements and protruding roof surfaces, special slats with a sealing layer are used. The installation technology is quite simple and does not require the use of special equipment.
This method of fastening is not used so often due to the high cost and the likelihood of depressurization of the seams. There are no guarantees that the canvas installed with adhesive adhesion will last longer than with other methods.
It should be noted that some manufacturers have introduced EPDM membranes to the market, the installation of which occurs using hot air welding, but their pricing policy is much higher than that of materials of this type.
3. Heat welding method
The technology for installing PVC and TPO membranes requires the use of special welding equipment. For attaching material to large areas special equipment is used, the welding process occurs automatically. The process speed, temperature and other parameters are controlled electronically. The equipment slowly moves along the seam, welding the sheets occurs overlapping using hot air.
Thus, the joints of the canvases are absolutely sealed and withstand a greater tensile load compared to the canvas. Welding machines supply a stream of air whose temperature does not exceed 500 degrees. Width weld seam ranges from 2 to 10 cm.
For mounting in hard to reach areas roofs use manual welding machines and special wheels to press the sheet, heated to a soft state.
4. Mechanical connection method
This method of fastening is considered the most popular; it is suitable for all roof shapes, as well as when truss structure does not have the strength to perform the ballast fastening method and there is no possibility of using the adhesive method.
The basis for the flooring can be profiled sheet or reinforced concrete. Mechanical fixation The membrane fabric is installed using galvanized self-tapping screws, which are placed at the seams. To fix the edges to the protruding surfaces of the roof, special edge strips with a sealing layer on the reverse side are used.
To fasten the canvases, telescopic fasteners are used, consisting of plastic umbrellas with a wide cap or disk holders of large diameters (if the roof has a slope of more than 10 degrees).
The pitch between fasteners should not be more than 0.2 m.
When installing the covering directly on the roof base, in order to avoid damage to the membrane, it is recommended to lay any non-woven synthetic fabric.
Features of installing different types of membrane roofing
- The choice of covering material for a membrane roof is of great importance.
- All types of membranes are suitable for the device using the ballast method.
- At mechanical method connections with self-tapping screws, the elasticity of the coating is not required, so a TPO membrane is suitable.
- If the fabric is joined by welding and the fasteners are made manually, it is recommended to buy material without reinforcements.
- The PVC membrane should be attached so that it does not come into contact with materials that contain oil, bitumen and solvents, otherwise this will negatively affect the quality of the coating. Therefore, it is recommended to separate the membrane and the above substances with a layer of polystyrene foam.
Issue cost
The price of membrane roofing depends on the manufacturer and the materials from which it is made.
Below are indicative prices for materials:
- Roofing sheet:
- PVC membrane - 270-750 rub./m2.
- PVC membrane (unreinforced) – 500-850 rub./m2.
- EPDM membrane – 250-720 RUR/m2.
- TPO membrane – 300-525 rub./m2.
- Related materials:
- Laminated tin – 1100-1550 RUR/m2.
- PVC overflows - 950-5900 rub./m2.
- TPO overflows - 820-5100 rub./m2.
- Vapor barrier – 40-90 rub./m2.
- Glue, solvent – 1000-35000 rubles/piece.
- Fasteners – 150 rub./m.
- Cost of installation work:
- Roofing decking – from 150 rub./m2.
- Vapor barrier layer - from 20 rub./m2.
- Thermal insulation layer – from 20 rub./m2.
- Profiled flooring - from 120 rubles/m2.
- Separating layer made of geofabric - from 30 rub./m2.
We make repairs
Repair of the polymer membrane is required in case of leaks, peeling of the sheet from the base of the roof and damage to the integrity of the sheet.
1. Current repairs
In case of damage to a small area of the roof, a spot repair method is performed.
A small flap corresponding to the size of the area to be repaired is cut out of the membrane. Using a welding machine, the flap is attached to the damaged area, while the base melts and is tightly connected to the patch.
If there is significant damage, several methods are used for repair:
- Repair without removing the old coating. To pre-cleared of debris old surface The coating is primed with a primer, after which a new layer is coated by welding. This method is recommended in case of multiple minor injuries.
- Repair with dismantling of the old canvas. Before laying a new layer of coating, the surface is cleared of debris, then covered with a primer of at least two or three layers.
2. Major renovation
It is required in the case when the installation process was disrupted during the installation of the roofing, and routine repairs were not carried out in a timely manner. Then it is necessary to replace all layers: insulation, vapor barrier, and sometimes screed.
Membrane roofing in winter
Polymer membranes do not lose their characteristics even when exposed to low temperatures. They are not afraid of the loads created by snow and ice. Usually snow removal is not required, but sometimes it has to be done (when there is equipment on the roof).
To do this, you should follow some rules:
- Clean using a wooden shovel (metal ones can damage the integrity of the coating);
- Leave a snow protection layer no more than 10 cm high on the roof plane (it will protect the membrane from damage and movement on its surface).
- There is an opinion that membrane roofing is only suitable for flat or low-slope roofs, but this is not true. Polymer sheets can be laid on roofs of various configurations.
- Roof installation should be carried out with special care. The slightest violations can lead to depressurization of the roof.
- When calculating the required amount of material, it should be taken into account that the sheet is laid with an allowance, and the sheet must cover the fence.
- It is periodically necessary to clean the roof surface, carry out preventive inspections, and routine repairs.
- The ballast method of installing the membrane can be used exclusively on roofs with a large load.
- The mechanical installation method is used when the roof truss system and the foundation of the building are not intended for heavy operating loads.
- After joining, it is recommended to test the quality of the seams by conducting a test. Use a flat-head screwdriver to run along the seams so you can find any gaps in the joint.
Membrane roofing is a modern type of roof covering. When creating a roof of this type, special membrane materials are used.
Despite the novelty of this technology, everything necessary components are presented in abundance in the retail chain, so from this side the installation of a membrane roof will not cause any difficulties.
Installation of membrane roofing is carried out without special tools, so if necessary, all work can be done independently.
What materials will be needed?
First of all, membrane roofing is suitable for arranging roofs with straight or slightly inclined slopes (their slope should be no more than 15º) of the correct geometric shape.
The great advantages of membrane roofing include the ability to install it over an old, worn-out coating.
The membrane roof covering is a reinforced film one and a half to two millimeters thick. A square meter of membrane coating weighs a maximum of one and a half kilograms.
Installation of membrane roofs takes half as much time as, for example, the creation of a TechnoNIKOL polymer-bitumen coating.
The membrane fabric has high puncture resistance, is not afraid of temperature changes, and does not collapse under the influence of ultraviolet radiation.
Membrane roofs can be made from different types of roofing membranes. Each of them has its own pros and cons.
The most popular membranes are made of PVC. They are made from plasticized polyvinyl chloride, and a polyester mesh runs through the thickness of the material. To make the PVC membrane elastic, plasticizers are added to polyvinyl chloride.
The PVC membrane is durable and reliable. It is installed by melting it with hot air, for which a construction hair dryer is used.
The technology using a hair dryer is safe and allows you to obtain a durable monolithic coating without the risk of damaging the materials or causing injury to yourself.
The weld seam on PVC membranes is so strong that the joined panel is not inferior in strength to a solid one.
The disadvantages of this material include low environmental friendliness - PVC membranes are isolated in environment volatile compounds. In addition, the material is not resistant to oils, solvents and bitumen resins.
EPDM membranes are made from synthetic rubber and reinforced with polyester threads. EPDM membranes are cheaper than other membranes, last a long time, have good elasticity, making them easy to install.
The canvases are not welded, but glued together with special glue. The main disadvantage of this material is that the joints of the canvases are not strong enough.
To prevent leaks on the roof, from time to time it is necessary to carry out routine repairs to the roofing, re-gluing the loose seams.
TPO membranes are made from alkenes. They can be made of reinforced fiberglass or polyester. Non-reinforced products are also available on sale.
The membranes are connected to each other by welding using hot air. This allows you to get a strong seam. TPO membranes are the most inelastic, making them the most difficult to install.
All of the membranes listed can be mounted on a roof of any shape and any degree of inclination. They meet fire safety standards and can withstand significant mechanical loads.
The installation of a membrane roof will require the purchase of telescopic fasteners and insulation ( mineral wool), vapor barrier film and corrugated sheet for flooring.
Methods for securing the membrane sheet
Membranes are welded using hot air or a solvent. Sometimes double-sided adhesive tapes are used to connect the canvases.
This technology for installing membrane roofing is simple and affordable; it does not require the use of special equipment.
But as mentioned above, the adhesive connection is not durable - the welded method is much more reliable.
PVC and TPO membrane sheets are joined by welding, spreading them over the roof and heating them at the edges with hot air.
After the material cools, a solid sheet is formed, equal to area roofs. The welded seams are absolutely sealed and resistant to tearing no less than the fabric itself.
Professionals use specially designed welding machines to heat the membrane sheet, capable of producing a stream of hot air heated to 600ºC.
Welding machines used when installing membrane roofing are easy to use. They are a unit on small wheels that just need to be carefully rolled over the seam.
For welding to be successful, you need:
- Before passing the welding machine, clean the surface of the membrane roof from all contaminants, including grease and chemicals;
- lay the sheets loosely, without tension, with an overlap of at least 5 centimeters.
Welding can be done using construction hair dryer with a special nozzle. The hairdryer is set to 550ºC.
First, test welding is done, checking the correctness of the selected operating parameters of the power tool.
After the trial welding, a test is carried out. If the welding quality is high, the membrane material will tear outside the welding zone.
If the temperature is too high, the membrane will burn and will not sinter. If the temperature is too low, the membrane will stick together, but will not cook.
Before welding, the sheet is pinched along the edges with telescopic fasteners every 50 centimeters.
The hair dryer nozzle is placed between the upper and lower edges of the two sheets and guided without jerking. With the other hand, roll the heated material with a hand roller.
After completing the welding, it is imperative to check that the width of each seam is at least 2 cm. If a defect is found in the weld, then install a patch from the same fabric.
The patch is made in a round shape; it should be wider and longer than the hole by at least five centimeters.
Welding a membrane roof does not require special skills, but it will require special tool. The ballast method of securing the membrane sheet does not have this drawback.
Ballast technology is used on flat roofs and on slopes whose slope is no more than 15º.
Ballast technology for fastening soft roofs is designed for buildings bearing structures and the floors of which can withstand heavy loads.
When ballasting the web:
- rolls are rolled out on a prepared base;
- along the perimeter of the roof and at the junction with vertical elements, the canvas is secured with adhesive tape;
- ballast is poured onto the roof with a continuous carpet - on square meter The canvas must contain at least 50 kilograms of ballast.
Crushed stone, large pebbles, concrete blocks or paving slabs. If the ballast has sharp edges and can damage the membrane roof, then the membrane sheet is covered with non-woven material before backfilling.
By laying paving slabs on top of the membrane, you can get a beautiful and durable roofing covering. Such a roof can be used not only to protect the building from bad weather, but also for recreational or household purposes.
Installation of the base for the membrane sheet
Membrane roofing is often installed on corrugated roofs. This technique makes it possible to insulate hangars, warehouses, and retail premises.
Roof installation consists of the following steps:
- rolls of vapor barrier material are rolled out along the corrugated sheet across or along the wave (it doesn’t matter);
- the vapor barrier should overlap; there is no need to glue or weld the panels;
- Insulation boards are laid out along the vapor barrier, preferably in two layers and always in a checkerboard pattern;
- the insulation is attached to the corrugated sheet with self-tapping screws or telescopic bases;
- Membrane fabric is spread over the insulation layer overlapping;
- in places adjacent to parapets and other vertical elements, the fabric is fixed using professional hair dryers;
- a glass welded from membrane fabric using a hair dryer is placed on the round vertical pipes coming out of the roof;
- the glass along its entire length is welded to the pipe, and from below it is welded to the roof.
When installing the roof, you must adhere to the following recommendations:
- Contrary to existing opinion, membrane roofs are designed not only for flat concrete roofs - they can be mounted on roofs of various configurations and on any base;
- the slightest deviation from the technology will lead to depressurization of the roof;
- when calculating the material, you must remember to make an allowance for overlaps;
- if the rafters are not designed for heavy loads, then use a mechanical method of fastening the membrane sheet (glue or welding);
- if the roof and ceilings are strong enough, then it makes sense to use ballast fastening;
- After welding, it is worth testing the quality of the seams - to do this, run a flat screwdriver along them.
By running a screwdriver along the seam, you can make sure that there are no holes opening in it anywhere.
Membrane roofs are not afraid of snow and ice. They are sealed, so there is no need to remove snow from them.
But if you still have to clean the roof in winter, for example, because there is some equipment on it, then you cannot scrape off the snow completely - you need to leave at least 10 centimeters of snow cover on the membrane, which will perform protective functions.
So, membrane roofing is a sealed, warm and durable roof cladding. This coating lasts 20 - 30 years.
It can be installed in the shortest possible time, since it consists of only three layers: vapor barrier, insulation and the membrane itself, which plays the role of waterproofing.
Membrane roofing has excellent waterproofing characteristics. The material can be mounted both on a prepared roof base and on an old roof covering during roof repair.
Scope of application and types of material
Installation of membrane roofing is primarily in demand when arranging flat roofs and roofs with a slight slope angle. The ability to install the membrane without dismantling the roof covering, which has lost its reliability, significantly simplifies and reduces the cost of roof repair.
The use of membrane materials on flat roofs allows you to create a serviceable roof. The advantages of this type of coating, primarily laid by the heat-welding method, include high waterproofing properties, due to which additional waterproofing is not required roofing pie. The membrane can be made from various materials - PVC, EPDM, TPO membranes.
When choosing a material, you should pay attention to the technology of laying the sheets: PVC and TPO membranes are installed using hot air welding, EPDM membranes are installed using the adhesive method.
The heat-welding method requires the use of specialized equipment and certain skills in working with it. Installation using adhesives or double-sided adhesive tapes, or using mechanical fasteners, can be done on your own.
Installation of membrane covering
The material is laid in one layer, thanks to which the installation of the roofing is carried out quite quickly. The membrane has a thickness of 0.8 to 2 mm, 1 square meter of material weighs on average about 1.3 kg. Compared to the installation of a bitumen-polymer coating, roofing made of membrane material takes half the time.
Durable, puncture resistant, resistant to temperature changes and ultraviolet radiation. The membrane can be laid on any type of base. Depending on the roof configuration, the presence of parapets, drains and other elements, the installation technology is selected. It could be:
- ballast mounting;
- adhesive connection;
- heat welded connection;
- mechanical fastening.
The membrane material sheets are connected to each other using adhesive tape or by welding.
Adhesive connection of sheets
To make a one-piece membrane coating from strips of rolled material, you can use special double-sided adhesive tapes. The advantage of this installation method is a simple and accessible technology that does not require the use of special equipment. But it should be noted that the adhesive connection of seams is not characterized by high reliability and durability, unlike the welded method.
The adhesive is susceptible to deterioration, and over time, such a roof may require repairs at the joints.
Joining the sheets using glue requires the installation of a membrane roof made of a material based on synthetic rubber. Recently, a number of manufacturers have begun producing EPDM membranes designed for hot air welding, but their cost is significantly higher than that of traditional materials of this type.
Heat welded connection of sheets
Membrane roofing, the installation technology of which requires the use of special welding equipment, is made of PVC and TPO membranes. This method involves welding sheets of roofing material overlapping using hot air. Joints made by welding can withstand a higher tensile load than the fabric itself and are completely airtight.
Welding machines maintain an optimal level of heating of the material by supplying a stream of air heated to 400-600 degrees. Width weld can range from 20 to 100 mm. For welding sheets over large areas, special automatic equipment for membrane roofing. Devices equipped with wheels move smoothly along the seam, high-quality welding of which is carried out automatically. Welding speed, temperature and other parameters are controlled electronically.
For installation in hard-to-reach places, arrangement of junctions, curved sections, complex assemblies, the use of manual welding machines and special rollers for rolling material heated to a plastic state is required.
To ensure high welding quality it is required:
- monitor the cleanliness of the surface of the material being welded (dust, dirt and traces of various substances must be removed before installation);
- lay the membrane without tension;
- create an overlap with a width of 50 mm (to ensure a weld with a width of at least 20 mm);
- After installation, it is necessary to check the quality of each seam.
If a defect is detected in the weld or damage to the membrane, a patch of the same material should be installed. The installation technology requires welding a piece of fabric with rounded edges, which is at least 50 mm in length and width greater than the size of the damage.
To pick up optimal mode operation of the welding machine in current weather conditions, it is recommended to perform test welding first.
Step-by-step instructions for installing a membrane roof can be obtained by watching the video.
Ballast fastening of membranes to the base
Laying membrane roofing using the ballast method can be used in cases where the roof slope angle does not exceed 15 degrees. This technology It is economical and is used when arranging flat roofs. Work progress:
- the base is thoroughly cleaned of debris;
- the canvas is laid on the base and secured by welding or glue around the perimeter, as well as in places where the base interfaces with vertical structures;
- to press the canvas to the base, ballast is laid at a rate of at least 50 kg per 1 sq.m.;
- bulk ballast must be carefully leveled.
The material for ballast can be:
- gravel, crushed stone (20-40 mm);
- large pebbles;
- concrete blocks;
- paving slabs;
- any massive objects.
Before laying ballast that can damage the membrane (broken stone, untreated gravel), you should lay a non-woven fabric or lay mats. The use of paving slabs as ballast allows you to create a reliable and aesthetically pleasing flat roof.
This method of fastening the covering can only be used on roofs designed for a high total load.
Adhesive and mechanical fastening of membranes to the base
The membrane sheet is attached to the base using an adhesive when laid on the roof complex shape. In addition, this installation option is practiced when installing roofs that experience high wind loads. The use of assembly adhesive allows you to install a membrane roof on a base made of reinforced concrete, profiled sheets, or wood. The canvases are welded or glued together. To strengthen the coating on protruding elements and roof edges, special edge strips equipped with a sealing layer are used.
Roofing materials based on bitumen have a number of disadvantages that reduce their service life and limit their scope of application. This prompted developers to create a new generation of rolled waterproofing materials - polymer membranes.
Membrane roof installation
Roofs with a membrane coating are structurally practically no different from other types of soft roofing, only instead of roofing felt or rubemast, material made of petroleum-polymer resins or synthetic rubber is laid on top. There are three options for roofing pie for such coverings.
Traditional soft roof with concrete base
Traditional roofing constructed on unused roofs made of hollow or ribbed reinforced concrete slabs. In this case, the following sequence of layers is maintained (from bottom to top):
Inversion roofing
Inverted is called exploited concrete roof, in which the traditional order of layers is slightly changed: the membrane is located under the insulation. On such a roof there can be a cafe, a parking lot or a lawn. The order of layers here is as follows:
Pitched roof with rafter system
Pitched design rafter roof looks like this (from bottom to top):
Advantages of roofing membranes and their types
Roofing polymer membranes are superior to rolled bitumen-polymer materials (BPM) in all characteristics.
The only drawback in comparison with the BPM is high price. But over many years of operation, the cost of maintaining a membrane coating due to the durability of the latter turns out to be half as much as compared to BPM.
Roofing membranes are made from:
Synthetic ethylene-propylene-diene rubbers EPDM and EPDM
The first roofing membranes were rubber and, despite the emergence of more advanced varieties, they are still produced to this day. This is explained by their following advantages:
- low cost;
- no need to use special equipment during installation;
- resistance to solvents, oils and bitumen.
Panels of EPDM and EPDM membranes are held together with a special glue - this is their only, but rather significant drawback. The membrane itself correct installation and operation, according to calculations, it can last up to fifty years (proven service life is 40 years), but the seams come apart much earlier. They have to be re-glued periodically, and if this is not done in a timely manner, the coating will leak.
In Russia, rubber (SKEPT) membranes “Cromel” and “Rukril” are produced. They are not inferior in quality to foreign analogues, for example, from Carlisle Syntes Systems and Firestone (USA), but they cost half as much.
EPDM and EPDM membranes are produced in three versions:
- soft;
- rigid (reinforced with synthetic mesh);
- with reflective coating (for hot climates).
Polyvinyl chloride (PVC)
PVC membranes are more expensive than rubber ones, but have an important advantage: polyvinyl chloride is a thermoplastic, that is, after heating to a state of softening and removing the thermal load, its physicochemical properties do not change, therefore individual panels can be joined by heat welding (heating with hot air) into a solid coating . The seams in such a membrane do not come apart and do not leak, even if the coating is constantly under water.
In terms of durability, PVC membranes are practically not inferior to rubber ones: the proven service life is 35 years.
Flaws:
- are not resistant to oils, solvents and bitumen, which requires taking appropriate safety measures during transportation and storage;
- installation requires special equipment.
It is the need to use special tools for welding PVC that does not allow this type of membrane to completely replace rubber products, which are still in demand.
Thermoplastic olefin elastomers (TPO)
The material, like PVC, is joined by heat welding. Unlike polyvinyl chloride, it does not emit harmful volatile substances, but it is much inferior to other membranes in plasticity.
Connecting TPO-membrane sheets requires the use of special equipment Membrane roofing: installation technology
During installation, the rolls are simply unrolled on the roof. Leveling the base is not required - unevenness does not harm the elastic membrane. There is also no need to remove the old roofing - you just need to cover its sharp elements with two layers of geotextile.
- panels are glued or welded;
- fix the membrane on the roof.
Let's look at them in more detail.
Adhesive connection of sheets
Membranes made of synthetic rubber (EPDM and EPDM) are glued together. The procedure is as follows.
- The panels to be joined are laid with an overlap of 150 mm.
- On the lower panel, make several marks with a marker along the entire edge of the upper one, indicating the width of the overlap.
Along the edge of the top panel, use chalk or a marker to mark the boundaries of glue application - On the top panel, at a distance of 300 mm from the edge, a series of glue strokes are applied to temporarily fix the folded edge.
Glue strips are needed to temporarily fix the edge of the top panel - The edge of the top panel is folded back and pressed against the previously applied glue stains.
The edge of the upper strip of the membrane is bent outward along its entire length and lightly pressed in places where adhesive tracks are applied - Both panels in the overlap area are coated with glue. When applying the composition to the bottom panel, they are guided by the marks made with a marker.
Using a special brush, an adhesive composition is applied to the lower and upper membrane panels along the entire length of the seam - A special tape with a glossy-smooth surface is placed on the area of the bottom panel greased with glue so that its edge protrudes beyond the marker marks.
An auxiliary tape is placed on the glue-smeared edge of the lower membrane - The bent edge of the top panel is peeled off and returned to its normal position, placing it on tape, which prevents the panels from sticking together, allows them to be smoothed and a complete fit is achieved.
The bent edge of the top panel is returned to its place - Holding the edge sticking out from under the top panel, the tape is gradually pulled out and immediately rolled over the overlap with a roller, pressing the panels together.
The auxiliary tape is gradually pulled out from under the membrane, and the edge of the upper panel is carefully pressed against the lower one, smoothing the seam with a brush
Gluing panels should not be done in windy weather: debris will get into the joints and the seam will turn out to be of poor quality.
Video: technology for gluing EPDM membranes
Heat welded connection of sheets
Hot air welding is used to join PVC and TPO membranes. The quality of the seam depends on a number of parameters:
- heating temperatures;
- the width of the welding machine nozzle, that is, the width of the seam;
- welding speed;
- pressure forces on the welded edges.
Heating temperature - the most important parameter. Both underheating and overheating are dangerous. In the first case, the edges of the panels will stick, but will not fuse into a monolithic seam, and such a connection will separate at the slightest load. In the second, a so-called temperature shock will occur: the polymer molecules will break up into small compounds and the material will lose strength. The difficulty is that optimal value heating temperature depends on the ambient temperature and, to some extent, on its relative humidity.
Welding of panels is carried out using a construction hair dryer equipped with nozzles 20 and 40 mm wide For example, at an air temperature of +25 o C, normal humidity(40–60%) and a nozzle width of 40 mm, the optimal heating temperature is 560 o C.
To accurately select all parameters in accordance with current weather conditions, test welding is carried out before installation. They connect two small fragments of the membrane and then try to tear them apart along the seam. Based on the test results, the following conclusions are drawn:
- the rupture occurred outside the seam - the welding parameters were selected correctly;
- rupture along the seam - the material is overheated;
- the panels in the seam area peeled off from each other - the temperature turned out to be low.
Test welding is performed each time after:
- long shutdowns of the device, during which it has time to cool down;
- significant changes weather conditions.
Having installed optimal parameters, begin installation.
Video: hot air welding of PVC membrane
Junction nodes
Adjacent to vertical structures- walls, parapets, ventilation pipes - are designed as follows.
Video: installation of external and internal corners of a PVC membrane roof
Features of making T-shaped seams
Often a long panel has to be assembled from two or more pieces. In this case, the transverse seams are welded first, and then the longitudinal ones. The result is a T-shaped seam.
It is not recommended to place transverse seams on the same straight line: they should be offset from each other Transverse seams are arranged staggered - with a shift. The intersection of four layers of material at one point is not allowed. The corners of the panels are rounded for a smooth transition from one panel to another.
The easiest way is to press down the membrane with a layer of crushed stone or gravel weighing 50 kg/m2. This method is possible under the following conditions:
- the roof slope does not exceed 15 o;
- the roof is capable of bearing the specified load (in addition to snow).
Large stones are used so that they are not blown away by the wind. If their corners and edges are sharp, geotextiles are first laid over the membrane.
In a ballasted roofing system, the membrane is laid loosely and covered with geotextile to protect it from damage. Instead of stones, you can lay paving slabs or concrete blocks on the surface.
Mechanical fastening method
If it is not possible to use ballast, the membrane is fixed with special fasteners.
- Bolts, anchors or self-tapping screws (depending on the type of base) with large plastic caps. Such caps are not capable of pushing through the material.
- For slopes over 10 o - with the specified hardware in combination with disk holders.
- On protruding roof elements - with special edge slats with a seal.
Only reinforced membranes can be fastened mechanically.
Special ones are available for fastening membranes. fasteners, the design of which eliminates damage to the roofing material Fasteners are installed along the seams in increments of 200 mm. If the slope is more than 2 o, an additional row of fastening elements is installed in the valleys.
Adhesive fastening of the membrane
The adhesive method is expensive and least reliable, therefore it is used as a last resort when other methods are excluded.
You can resort to continuous gluing of the membrane, but more often the glue is applied selectively:
- along the perimeter;
- along the seams;
- on the ribs;
- in the valleys;
- in places adjacent to vertical structures and pipes.
Equipment for installation of membrane roofing
The only specialized tool for installing roofing membranes is welding machine. It is used only when installing thermoplastic membranes - PVC and TPO. Welding is carried out without filler material.
Membrane welding machines are divided into three types:
- automatic;
- semi-automatic;
- manual.
Automatic devices
Automatic welding machines are large, heavy machines designed to weld straight, long seams on a core, easily accessible part of a horizontal or vertical surface. Here are their advantages:
- accurately maintain optimal temperature, welding speed and pressure on the surfaces being joined for current weather conditions, which ensures high quality welds;
- provide optimal consumption air (relevant for TPO membranes);
- long sections are welded with consistently high quality, whereas when manually welding such seams, due to monotonous work, the human factor is especially pronounced and, as a result, the quality suffers greatly;
- do not require high qualifications from the operator - he only adjusts the parameters and corrects the direction of movement of the machine along the seam.
In addition to quality, the automatic device provides high installation speed - 2–8 meters per minute (m/min). With the manual method, the welding speed is no more than 0.4 m/min.
The automatic welding machine ensures high installation speed and stable quality of the weld seam Semi-automatic devices
Semi-automatic devices are used in places where it is impossible to use a massive machine: on roofs with a large slope, vertical surfaces, parapets and other structures. They also provide high speed and good quality assembly seam, but are much inferior in these parameters to automatic devices.
Semi-automatic installations are used when performing work on vertical sections, parapets and roofs with a large slope Manual hot air guns
Manual devices are used in complex and hard-to-reach places where the roof covering adjoins various designs, on curved sections, when welding short end seams. A manual welding machine is called a hot air gun. It is lightweight and easy to use, with emergency situations automatically turns off. Operating mode parameters are shown on the display. The air temperature is stepwise regulated by a 10-position switch in 60-degree increments. The most advanced models maintain the required temperature automatically.
Hair dryers are designed for welding membranes in hard-to-reach places and for installing membrane roofs of small areas Leading manufacturers of equipment for welding membrane roofs
Equipment for welding TPO and PVC membranes is produced by companies in Switzerland, the USA, Germany, and Sweden.
Leester Process Technologies (Switzerland)
Highest rating The following models received users:
Forsthoff Gmbh (Germany)
Forsthoff GmbH is constantly improving its products. Thus, in the manual welding machines of the “S” series, released in 2009 (Grand-S Electronic, Hot Air S, Quick-S Electronic, etc.), the following solutions were used:
Herz (Germany)
In addition to hot air guns, the catalog of this manufacturer includes testers for checking the quality of welds and much other equipment. Most in demand Laron automatic welding machine and Rion manual welding machine are used, while models of the Eron, Mion and Comon series are used quite rarely when installing roofing membranes.
High productivity (up to 7 m/min) of the Laron machine allows you to significantly reduce the time required for installation work Lansite (USA)
The company produces high-quality hand-held devices budget segment. The assortment is represented by two series - Tornado and Hurricane.
Sievert(Sweden)
Creator of the reliable automatic welding machine SievertTW 5000, popular among professionals. The Penoplex St. Petersburg company even officially recommends using it when installing its Plastfoil membranes. Features of the device:
- propulsion system with all-wheel drive (the quality of the weld increases regardless of the thickness of the membrane);
- adjustable front wheels allow welding under different angles;
- powerful engine provides ascent along a slope with a slope of up to 30 o.
Video: machines and accessories for welding PVC membranes
Polymer waterproofing membranes- almost perfect roofing material: they are durable, elastic, resistant to all negative atmospheric factors. But the coating will live up to expectations only if it is installed correctly, so it is advisable to trust it to certified specialists.