Covering a soft roof with liquid rubber. Roof repair with liquid rubber. Disadvantages of conventional repair methods

Liquid rubber has recently gained increasing popularity as a material for roof waterproofing. Most often, liquid rubber is used to apply a coating to a flat surface. The use of liquid rubber on surfaces with a large area is one of the most convenient options, since when working with this material, it is very easy to apply a coating even to complex parts of the roof topography.

What are the advantages of liquid rubber

It is worth noting that liquid rubber also has a number of undeniable advantages. These include, in particular:

• ease of application with high labor productivity;
• chemical resistance and environmental friendliness;
• Fire safety;
• reliable roof covering;
• high elasticity;
• no seams;
• resistance to various types of weather conditions and ultraviolet rays;
• complete protection from moisture;
• durability.

It is more convenient to use than roll and membrane coatings. Currently, this is one of the most modern types of roof waterproofing. Liquid rubber can be used both in the reconstruction of old buildings and in the construction of new construction projects. The most important advantage of this material is its versatility. The connection to the base occurs at the molecular level, due to which very high reliability of fastening is achieved, regardless of the texture or material of the roof.

However, to be fair, its shortcomings should also be pointed out. Firstly, the cost of liquid rubber is quite substantial. Secondly, it has a fairly high sensitivity to solvents and substances that include petroleum products. Thirdly, it will be possible to remove liquid rubber already applied to the surface, if such a need suddenly arises, only mechanically.

When covering the roof with liquid rubber, you should take into account the specific application of this material.

The most obvious way to see the coating of a roof with liquid rubber is when applying such a coating to roofs that have a complex slope structure, or when working on large areas. The peculiarity of liquid rubber is its very wide scope of application, and this material can be applied even to an old coating: it only needs to be cleaned of debris.

Roof coating with liquid rubber is carried out in one of three ways:

• bulk;
• coloring;
• cold spraying.

However, regardless of which method is used, before starting work, you should thoroughly clean the base on which the liquid rubber coating will be applied. Remember that the preparatory stage is very important, since the final result largely depends on it, so the old coating should be cleaned of grainy toppings as much as possible and the exfoliated roofing material should be completely removed. You need to remove all the dirt, all the debris, and then get rid of the dust. Applying liquid rubber over old roofing material requires the mandatory installation of deflectors that draw moisture out of the roofing pie. In addition, in some cases it is recommended to reinforce the waterproofing layer with geotextiles.

Let's move on to a more detailed look at how to apply a liquid rubber coating to a roof.

1. One of the ways to apply it is the pouring method. After clearing the surface of debris, you need to saturate the base with bitumen emulsion. The thickness of this layer (also called primer) should be from 1 to 2 millimeters. After this, liquid rubber is immediately applied to the base. It should be applied in certain portions, evenly distributed over the surface using special rollers.

The thickness of this layer should be from 2 to 3 millimeters. It should be noted that bitumen-latex mastic only needs a few seconds for it to begin to set, but in order for the job to be done efficiently, the applied layer should be allowed to sit for at least 5 minutes. After waiting the required time, you can begin applying the next layer - in most cases this is already the finishing layer. The pouring method is used for flat surfaces, helping to level the roof itself as much as possible. For pitched roofs, the use of this option is, as a rule, not practiced.

1. The next step is to apply the base layer - at this stage the rubber mastic is no longer diluted with water. Using a spatula, apply the composition to the surface so that you end up with a layer 2 to 3 millimeters thick - a wide brush will also work for this work. The applied layer will dry completely after at least 48 hours. To ensure that the application of the second layer is as uniform as possible, it is recommended to apply it perpendicular to the direction in which you applied the primer - with this order of work, the liquid rubber will fully comply with all the declared characteristics. Note that this method is best suited for pitched roofs and small surfaces, when, from a financial point of view, it is simply unprofitable to use mechanical equipment.

1. And finally, the last method is the spraying method. As mentioned above, first of all, the base is carefully prepared, after which you can begin to directly treat the surface with liquid rubber by spraying. To do this, a special device should be connected to 2 containers. One of them contains a polymer-bitumen emulsion, the second contains calcium chloride, which acts as a hardener. Both of these components must be fed into the nozzle at the same time, they are mixed before spraying onto the surface.

Surface treatment with liquid rubber by spraying is in most cases used over large areas or on sloped roofs. The advantages of this method include, first of all, the speed of work and the quality of applying the rubber layer. The applied material hardens almost immediately, meaning there is no need to wait for the rubber to harden. In addition, the spraying method can be used on any surface. The material here is applied using a sprayer, which means that you can handle even the most bizarre designs without any problems.

Before you begin waterproofing or repairing a flat roof with liquid rubber, you must first complete all general construction work on site. So that after the formation of a seamless bitumen-polymer membrane on the roof surface, no strangers move on the coating, much less carry out loading and unloading work and transportation of building materials, equipment, etc. on the roof. This is possible if the liquid rubber membrane is protected from mechanical damage. For example, cover it with geotextiles and arrange a screed.

There was once a case when a contractor completed flat roof repair, technical supervision accepted the work. In August, all of a sudden, the customer reports leaks. We went out onto the roof and found that the covering was torn in many places.

It turned out that a week ago large stained glass windows were installed in the attic extension of the neighboring section of the house. Huge windows, weighing a hundred kilograms each, were lowered by crane onto the rubber roof, then several people, using their hands and carts, dragged these windows 50 meters, then installed them... The result is damage to the coating. Then it started to rain.

It’s good that all this came to light in the summer - the damage was eliminated, since the coating made of two-component liquid rubber can be easily “healed” with one-component liquid rubber. But things don't always work out so well. And the customer may not admit his guilt and the damage may be discovered in November, when it will no longer be possible to use liquid rubber.

By the way, one-component liquid rubber is an ideal product for spot flat roof repair, when it is necessary to seal only the places of junctions, cuts, punctures, holes and other damage, or those areas where there were swellings that were opened to dry or install aerators. For these purposes, you do not need to use equipment, just a bucket of water-based bitumen-polymer mastic and a spatula. But again, work can only be carried out in the warm season.

So, the decision was made to repair the flat roof using a two-component water-based bitumen-latex emulsion, better known as liquid rubber.

Where should you start?

You need to start by completing all construction and installation work on the roof and adjacent areas, installing all mechanisms, equipment, and fixtures.

Surface cleaning for flat roof repair

The condition of the roof can be very different. With capital flat roof repair It is very likely that you will have to dismantle the old roll covering (and many layers), and then the thermal insulation, all saturated with moisture, and then the screed, all cracked and crumbling. That is, you will have to remove the entire old roofing pie - up to the reinforced concrete floor slab. And a flat roof during these operations may look like the one shown in the photo below.

The roof base must be clean. It makes no sense to bring the installation and liquid rubber to the site before the roof has been cleaned. All construction debris, leaves, dirt, dust, etc. should be removed.

How to remove construction waste is more or less clear. Most often, “misunderstandings” arise - how thoroughly should the roof be cleaned of dust and how to do it?

Here it should be understood that if dust remains and there is a lot of it and it is not emulsified during priming, then it will turn out that the coating will be applied not to the base, but to the separating layer. Accordingly, there will be no high-quality adhesion, accordingly... well, etc.

The “degree of cleanliness” of dust for flat roof repairs with liquid rubber also depends on the liquid rubber raw material used. The fact is that some brands are very “capricious” or, let’s call it “demanding” in terms of fulfilling all technological aspects, incl. and the absence of dust. Those. When using two different types of liquid rubber raw materials when repairing a flat roof, the result - in this case adhesion - will be different.

Some brands of bitumen-polymer emulsion can be applied even to a very dusty base and the adhesion will be such that you can tear the hell out of it. And another material can be applied even to a more or less clean surface and the membrane can be removed even after a few days. Of course, in addition to cleaning the base, other factors are important for adhesion - but more on that in other articles.

So, how clean should it be?

Dust removal of the base when repairing a flat roof with liquid rubber

The most effective way is to blow off the dust with a compressor. In this case, it would be good to provide screens so as not to blow the dust down, but to drive it onto one section of the flat roof and collect it there. It is optimal for the compressor to be equipped with an oil and moisture separator (excess moisture on the base, which will be covered with liquid rubber, is not needed). Each compressor usually has a built-in moisture separator, but this is not enough. It is better to install a separate oil and moisture separator at the outlet. Such devices are inexpensive and compact. In the photo below you can see the oil and water separator from the Italian company Camozzi.

A lot of dust and dirt accumulates at joints, junctions, roof mounting points for engineering equipment, pipes, antennas, air ducts, ventilation shafts, protruding metal structures, etc. Moreover, in these places the dirt, as they say, “cakes and grows together” with the base. You won't be able to blow it off with air. Such areas must be cleaned with special care, using wire brushes or brushes with dense, stiff bristles. You can use special brush attachments for drills.

From flat areas of a flat roof, caked dirt and dust can be removed by washing with water under pressure (various Karcher washing units). But the roof surface must be dried after such washing. And it is better not to apply such washing to the old rolled base of a flat roof (if the old covering is not removed), because... some of the water will definitely get under the roll and this will only complicate further work on preparing the base for flat roof repair.

If liquid rubber is to be applied on fresh concrete, then it is better to remove the cement laitance, because soon this layer will gather dust. Ideally, this problem can be solved by grinding the concrete. In this case, the upper fragile layer is cut off and pores are opened, which will be clogged when primed with a bitumen-polymer emulsion. If you want to do everything perfectly, use concrete grinders. Well, or, at least, go through it with brushes.

Here, again, it should be understood that when using some brands of liquid rubber, you can get excellent adhesion on concrete, even if you remove the cement laitance with brushes (provided that a primer has been completed before applying the liquid rubber). For other types of bitumen-polymer emulsion, in order to obtain good adhesion, you need to clean off the cement lait more thoroughly.

Repair of a flat roof with liquid rubber on a wet base

After the surface has been cleared of construction debris, dirt and dust, you can proceed directly to repairing the flat roof with liquid rubber. But... Only if the base is dry.

If it is known that the base is wet, not even from above, but rather there is moisture inside, then this is fraught with troubles later. Therefore, such a base should be dried. This applies to a lesser extent if liquid rubber is to be applied over a new screed, and to a greater extent when flat roof repair carried out on the old roll base without dismantling it. If there are many layers of rolls (sometimes there are 20 or 30 layers), then a lot of moisture has accumulated in such a cake. This is exactly the case with old roll coverings. And this water should, if possible, either be removed before applying liquid rubber or measures should be taken to ensure that this water is removed later, but so as not to damage the coating.

To learn how moisture accumulates in the roofing pie, what this leads to, and what should be done before applying liquid rubber when repairing a flat roof, read two articles on the site:

• Drying the base when repairing a flat roof
• Ventilation of the under-roof space

If all the preparatory stages are completed: construction work, the base is cleaned, dried, prepared and the ventilation issue is resolved, then the installation and liquid rubber can be delivered to the site.

When starting to apply bitumen-polymer emulsion, you should remember that installing waterproofing is only one stage in the technological chain for repairing a flat roof. Therefore, it is necessary to carry out a set of measures that differ depending on whether the roof is in use or not, in accordance with the technological map of the roof.

Everything that is necessary for proper waterproofing is described in detail at www.B2bB2c.ru. If you need something more than what is stated on this and other pages of the site, then the service from the Sales Department is available to your attention -

The modern construction industry does not stand still, offering users new and improved materials. Among the latest innovations in the field of roofing materials, the so-called liquid spray roofing stands out - a modern material that allows you to quickly and easily cover large areas of the roof and meets high requirements for tightness.

Let's consider the features of this material and the possibility of its use in private construction.

In this article

Material characteristics

Liquid roofing is a very functional and practical material, representing the synthesis of bitumen and latex. It is perfect for repair and restoration work on the roof. Due to its special ductility, it is often called liquid rubber.

The scope of application of this material is quite wide and is not limited only to roofing. It is used with great success in the repair of roads, tunnels, and for waterproofing various containers (swimming pools, fountains, etc.). One of the distinctive qualities of the coating is the ability to use it on any surface: metal, slate, wood, stone.

Liquid rubber is stored and supplied in separate hermetically sealed barrels. To apply this material to the surface, special equipment is required. For example, this could be a mobile installation for applying liquid roofing, which applies a substance - a cold emulsion - in a thin layer. Such a roof not only protects the building from precipitation, but is also safe in terms of fire - it is difficult to ignite. Liquid rubber can be used in roofing in any climatic conditions.

If liquid rubber is applied to concrete or brick, it is firmly fixed to the corresponding surfaces. Thanks to this, it becomes possible to create high-quality and durable seams. During roofing work, this material allows not only to strengthen the entire roof, but also to provide excellent sound insulation.

Thus, liquid rubber can be used to repair roofs covered with various roofing materials. The use of bitumen is possible on both flat and pitched roofs: the material hardens almost instantly after application. Hardening of liquid rubber occurs without the release of toxic vapors, since the material is based on water.

Advantages

The advantages include:

• Resistant to temperature changes and sun exposure;
• Resistance to various aggressive natural factors (wind, snow, rain, hail, etc.);
• High fire safety;
• Elasticity and absence of seams when spraying;
• Resistance to mechanical damage;
• Ease of operation and repair;
• High waterproofing;
• Long service life.

The advantages of this roof also include the possibility of installing it yourself: the material does not require special heating and is applied in a cold state.

Flaws

Of the minuses, it is worth noting, perhaps, only the fairly high cost per square meter of such a roof. On average, it will cost from 800 rubles per sq. m. m.

Types of liquid rubber

There are several types of liquid rubber for roofing, which are divided according to two parameters. The first of them is in composition:

• The one-component mass does not require any preparatory work and is immediately applied to the surface. The consistency is a viscous mass of various colors;
• The two-component mixture includes a base and a special curing composition and requires special preparation before application.

The material also differs in the method of its application to the surface:

• Applied to the surface like paint using a brush or roller, it creates a viscous substance that fills all microcracks in the base;
• When cold it is applied by spraying;
• It is laid using the self-leveling method, similar to self-leveling floors.

All types of liquid roofing have an important advantage over other roofing materials - it is amazing elasticity and stretchability. A thin, about 2 mm, section of bitumen does not tear under the influence of external force, but stretches. It is this, as well as the seamless fabric, that ensures the high level of waterproofing of this material.

Roofing process

The do-it-yourself roof treatment plan comes down to the following action plan:

• First of all, it is necessary to calculate the area of ​​the roof being treated. Based on these data, the required amount of waterproofing for the roof is calculated. As a rule, 1 kg of cold material is used to process 4 square meters. m of roofing, taking into account the application of two layers. It would not be superfluous to add 10% not unforeseen cases to the result obtained.
• It is recommended to purchase liquid bitumen for roofing at specialized sales points, where the material will have all the necessary documents, and competent consultants will help with valuable advice.
• Before applying the material to the roof, it is cleaned of dust and debris. It can be applied to a damp surface, but for best results it is still necessary to dry the roof. Application of liquid bitumen does not require the removal of the old roofing; the material fits perfectly on metal, wood, tiles, concrete or brick.
• Applying the material using one of the methods presented below, depending on the availability of special equipment, or on your own.
• Checking the tightness of the material.
• Finishing work on the roof. Liquid rubber can be painted with any water-based paints, which will make the new roof attractive and in harmony with the rest of the building.

Application options

Liquid roofing does not require special surface preparation before application: it is enough to clean the area of ​​debris and dust. Let's look at different ways of applying this material to the roof.

Sputtering

The most desirable method of application is the spraying method, as it has a number of undeniable advantages over other methods:

• Allows you to easily apply the material to all bends, junctions and complex geometric shapes of the roof;
• Significantly saves material and application time.

For spraying, a special spraying device with a gasoline engine is used, which, due to its relatively low weight (up to 70 kg) and mobility, allows you to quickly treat large areas of the roofing surface: up to 2 thousand square meters. meters per day. This method is the main one in industrial construction, as it allows, with maximum savings in material, to process the maximum amount of roof space at high speed.

Application by painting

In private construction, where it is often not possible or necessary to use special equipment, application is possible by painting using rollers or brushes.

In this case, the roof made of liquid rubber is thicker than in the case of spraying. On the one hand, this significantly increases the material consumption (from 2-3 times), but, on the other hand, it gives a thicker and, accordingly, more durable roofing covering.

Considering the relatively small scale of the roofs of private houses and buildings, this application method has a right to exist and is very popular among craftsmen who are accustomed to doing repairs with their own hands.

Liquid roof rubber is applied manually in several layers with a thickness of each layer of 3-4 mm. Allow at least 15 minutes between coats to allow the previous coat to dry and harden. It is important to ensure the evenness of the coating, using a spatula if necessary.

Bulk method

This method is similar to the previous one, with the difference that it allows the installation process to be carried out much faster. Liquid rubber is poured into the center of the surface to be treated and quickly leveled with rollers or spatulas.

In this case, it will be much more difficult to control the thickness of the layer, since due to rapid drying, all work will have to be done quickly.

conclusions

Liquid rubber is a fairly convenient material to use, combining high quality and operational advantages with the ability to quickly install it yourself. It is applied in one piece and without seams, so water does not leak through it in case of bad weather.

The ease of installation and unpretentiousness of the material make it an attractive coating both for roofs of any type and for repairing existing roofs.

Taking into account everything described above, we can confidently say that liquid rubber is a revolutionary building material that is perfect for complex roofing work.

If you've ever heard of so-called liquid rubber before, you've probably been surprised at how far technology has come. This material is difficult to replace when it comes to complex terrain, where the use of rolled materials is generally impossible. It is also excellent for arranging new structures and repairing old ones, as well as protecting important structural elements from corrosion. This material at the molecular level is able to adhere to almost any surface!

But waterproofing a roof with liquid rubber only at first glance seems like a simple and straightforward process. In fact, in order to end up with really high-quality waterproofing, you will have to strictly follow all the rules! And we will tell you all the details and nuances of the process itself.

Over time, with the improvement of construction technologies, increasingly serious demands are placed on roofing waterproofing materials: high properties and ease of carrying out the work itself. This is especially true for treating roofs with complex terrain and atypical building materials, which is not uncommon today.

Depending on what type of liquid rubber you will use, you will need special equipment, or you can get by with a regular bucket and roller.

For a one-component solution, a brush and normal manual application are sufficient. After all, such rubber is no different in consistency from ordinary mastic. But two-component rubber can only be sprayed using special mechanized equipment.

Waterproofing with two-component liquid rubber

We are talking about an airless spraying unit in which two components are supplied and mixed under pressure at once. Once exposed to the open sky, they quickly polymerize. And as a result, they have excellent adhesion without a single seam.

As a result, spraying liquid rubber using special equipment turns the whole job into a fairly simple and pleasant process:

The process of spraying roofing is quite interesting. What other roofing could you apply this way, so quickly? Moreover, even the most difficult task can be easily handled by only two workers.

Special equipment helps to achieve the exact thickness of the application, no more and no less. Which is very important, because liquid rubber is not a cheap material. The principle of such a unit is practically no different from the operation of a conventional spray gun.

It contains two tanks, one of which contains a polymer-bitumen emulsion, and the other contains a calcium chloride hardener. Both substances are supplied from pressurized containers, the components are mixed at the tip and fed through a small hole - thin enough to provide a coating thickness of 2.2 to 4.0 mm. Already in place, the components influence each other and solidify in the open air.

Moreover, the method of spraying under pressure differs significantly from the pneumatic one. Here, the loss of material into the environment is significantly reduced. In simple terms, no fog forms around the sprayer, and less solvent is introduced into the composition itself.

Thanks to all this, when working with liquid rubber, it is not necessary to wear a protective suit and mask, and the speed of the coating itself is much greater, because all the material is directed strictly at the roof and not into the air. And all the equipment for the work of one team easily fits into a small Gazelle-type car: catalyst, liquid rubber and installation.

Most often, liquid rubber is black, but the material itself is compatible with silicon-organic or water-based, but not chemical solvents. But today many types of colored liquid rubber are produced, but you can also paint your roof yourself with VD-AK-1503 paint, special for this undertaking, which can also be produced from a spray bottle. And this has another plus - additional protection of liquid rubber from ultraviolet radiation:

Experienced roofers can work with two types of color at once, applying one layer first and the second on top. What is it for? It's not about design at all!

This is how you can clearly see how well the new layer was sprayed, and whether it completely covered the previous one, or whether some places were missed. In addition, when spraying a top layer of a different color, it is clearly visible how correctly the base material is dispersed.

But when hiring a team for such work, keep in mind that you need to have a license to cover a roof with liquid rubber, because without training personnel it is impossible to spray such a coating efficiently, and the process has its pitfalls.

Waterproofing with one-component liquid rubber

Depending on the task, the desired area of ​​the roof is covered with liquid rubber with a thickness of 2 to 3 mm. At the same time, the coating has high elasticity and a wide temperature range from -45°C to +120°C. And the quality of the liquid rubber determines how smooth it will lie on the roof and how quickly it will harden.

First you should prepare the surface, repair all holes, chips and cracks. Ideally, you can thoroughly clean the dirt from the roof, which can be done with a pressurized water hose and detergent, if you have such an opportunity. And how smooth the surface is will affect the uniformity of rubber application:

Also, the corners of the junction with the wall and the exit of the roofing elements are treated in advance with a primer and even mastic:

Then, using a roller, spread the composition over the roof surface. Once the first coat has dried for 8-24 hours, apply the second coat.

The main thing is to carefully distribute the material over the entire surface:

The newly applied rubber instantly hardens to 80%, and continues to harden for another 48 hours, although it is already waterproof. Although after just 10 minutes you can safely walk on such a roof.

As a first step, calculate the required amount of liquid rubber for the roof. So, for a layer of 1 mm per square meter you will need from 1.35 to 1.65 kg of liquid. Also, a lot here depends on the base material on which the liquid rubber will be applied:

• the insulation layer for wooden and metal structures is 1.50 mm;
• the layer for concrete and reinforced concrete roofs should be from 3.2 to 4.0 mm;
• in case it is necessary to cover a membrane roof, then the layer should be 2.0 mm.

Make an accurate calculation, and you will buy neither more nor less. Moreover, liquid rubber is not a cheap material.

Repair of roofing elements with liquid rubber

Liquid rubber for roofing is one of the best materials for waterproofing and repair. Indeed, in addition to the fact that such a coating creates excellent water and sound insulation, liquid rubber itself helps strengthen the structure of the roof.

Liquid rubber can be applied directly to old layers of roofing felt roofing, without prior installation. This is why the material itself is valued, because it can be laid on old roofs. The only thing is that then deflectors are installed on the old surface to remove accumulated moisture.

For local repairs and waterproofing of the roof, one-component liquid rubber is more suitable for you, because it can be applied with a roller or brush. And at the same time, the final quality will be no worse than that of a two-component one! First you need to prepare the liquid rubber by stirring it well. Now use special paper or fabric pads to give the repaired surface more rigidity and a kind of reinforcement.

Restoring an old roof: preparation and application

This is what the liquid rubber waterproofing process looks like in practice. One-component rubber must be applied in two or three layers, with each of them pre-drying:

All waterproofing work should be carried out at a temperature of +5°C, spraying or applying rubber exclusively to a dry surface.

Local roof repair and waterproofing of junctions

If you are concerned about the quality of liquid rubber for repairs, then use well-known imported materials such as Premier Rubber Membrane. This is a composition of the Canadian company Cantex Coatings Ltd, which consists only of non-flammable liquids, without any organic volatile compounds.

You will recognize this product by its dark brown color and thick rubber coating. After complete drying, it will have particularly high elasticity, about 1500%, absolute water and vapor impermeability and excellent resistance to mechanical deformation.

Moreover, the repaired area will retain these properties for more than 25 years, according to the manufacturer, and this is with constant contact with water:

For comparison: liquid rubber applied to the repaired area in two layers (this is up to 2 mm) has the waterproofing properties of four layers of roofing material!

But there are some limitations when working with liquid rubber. For example, it is not allowed:

• Work in the rain, because... At high air humidity, liquid rubber will not have time to polymerize. But you can work with residual moisture in the base, because when it dries, the rubber will allow its water to evaporate.
• Apply rubber at air temperatures below +5°C, although sometimes this problem is solved by heating with guns.

All other weather factors will not interfere with the process. A fascinating process, isn't it?