Choosing a sealant for the roof. Roofing sealant: types, characteristics, instructions for use Polyurethane roofing sealant for metal

For quality device roofs correct installation roof covering is not enough - you need to take care of durable insulation of the most problem areas(areas for the location of additional parts, joints, etc.) from precipitation. For works of this type roofing sealant is used. The name is translated into Russian as “dry”, “inaccessible to air”, “tight”.

Material characteristics

The sealant is a special substance of a viscous, paste-like and fluid consistency, made on the basis of organosilicon and polysulfide liquid rubbers and polymers. It is used to ensure the tightness of various joints and connections. The substance is applied to bolts, rivets, and other connections.

Sealant– new generation material. Its distinctive qualities are strength, reliability, and elasticity. Important advantages of this substance are its moisture and air resistance. The choice of a specific sealant depends on the type of surface on which it will be used.

The substance retains its physical properties in a fairly wide temperature range: from minus 55 to plus 80 degrees.

Types of sealants

Depending on the base, all sealants are divided into four main types:

• silicone;
• bitumen;
• acrylic;
• polyurethane.

Silicone or rubber

The sealant type is the most common. The basis of the material is silicone rubber. Sold in 310 ml tubes. It is multifunctional: it is often used in everyday life for joints, moving external seams, when assembling panels, frames, verandas, when working with ceramics, wood and glass.

High degree resistance to sudden temperature fluctuations and ultraviolet radiation makes it very popular when working on roofing.

Silicone sealants, in turn, are divided into subtypes: vinegar (acetate) And neutral.

A distinctive feature of vinegar sealant is its significantly higher level of strength compared to neutral sealant.

It is suitable for use on smooth surfaces– for example, when working with glass. The main disadvantage acid sealant is the presence of a sharp pungent odor, which, however, quickly disappears after completely dry.

Neutral sealants They are completely odorless and less toxic. They are used for work in the bathroom, kitchen, and other rooms. The distinctive qualities of this subspecies are excellent adhesion to wood, glass, ceramic surfaces, enamel, porcelain, etc.

Bitumen sealant

Is used for metal roofing.

The material is developed on the basis of modified bitumen, to which aluminum pigment has been added. It is a fluid mass with a beautiful aluminum tint.

Among its advantages are super-strength, elasticity, and durability. The material is easy to paint and is not subject to aging. It has a high level of water resistance and excellent adhesion to both dry and wet surfaces.

This type of sealant is used to seal various voids, cracks and seams that form in a metal roof. They can be used to strengthen roof ridges, chimneys, gutters, ventilation and any other metal surfaces.

Since the material is very toxic, it can only be used when performing work on the outside of the building.

There are a few types of bitumen roofing sealant, which are resistant not only to snow, rain, sun rays, but also to solvents, various oils, gasoline and many other chemicals.

Sealants of this type are in most cases used for smoothing cracks, filling joints and seams in structures, smoothing joints in windows, walls, and floors. Their use is advisable at points where there is a risk of displacement of connected structures or parts under the influence of temperature fluctuations, mechanical loads, humidity, shrinkage, wind, vibration and sound.

Modern acrylic sealants are produced on the basis of siliconized modified additives. Their properties are identical to silicone High Quality, but more affordable.

Sealants of this type have excellent adhesion to brick, concrete, tiles, fiberboard, PVC, painted, varnished surfaces, porous substrates. They are resistant to temperature fluctuations, ultraviolet radiation, and can withstand heat, cold, excessive dryness and high humidity.

Acrylic sealants retain their qualities in the temperature range from minus 40 to plus 80 degrees and can withstand mechanical loads well.

This substance does not deteriorate when exposed to moisture: its water absorption is 0.5%. The material can be successfully used in conditions high humidity. Thanks to antifungal additives, the sealant protects surfaces from the development of mold and mildew.

Transparent acrylic based sealant appearance no different from silicone. It gives a perfectly transparent sealed seam, suitable for work both indoors and outdoors. They can be used to seal siding, ventilation openings, etc.

Polyurethane sealant is produced on the basis of polymerized special conditions resin. It is an elastic viscous homogeneous mass that can be easily applied to any surface. It is the most durable and reliable material, used for sealing. Although it is more expensive than other types, it fully pays for itself due to its quality characteristics and high degree of efficiency.

You can work with polyurethane sealant at fairly low temperatures Oh. They are sealed during repairs interpanel seams, produce insulation of double-glazed windows, swimming pools, winter gardens. A high degree of resistance to temperature fluctuations and high humidity allows the use of this substance in roofing works Oh.

There are several types of polyurethane sealants:

• sealing – intended for dry surfaces;

• waterproofing - for use in conditions of high humidity, as well as for surfaces in direct contact with water.

The substance is easy to apply and hardens quickly. It is very economical to use, since it requires a small amount of sealant to work.

The substance retains its quality characteristics for long period time, does not peel off and is not subject to destruction.

Polyurethane sealant is used to treat surfaces that need to be protected from moisture, ultraviolet radiation, and the proliferation of microorganisms. Usage of this material when carrying out roofing work allows to ensure elevated level strength of the constructed structure.

Polyurethane sealant comes in different degrees of hardness. When working on roof installation, sealing roof coverings, processing joints of metal, wood, concrete, polyvinyl chloride surfaces with building structures a substance with a hardness level of PU 15 is used. Surfaces made of reinforced concrete, concrete, glass and metal are treated with a sealant of hardness PU 40. For metal structures, material PU 50 is used.

Polyurethane sealant is resistant to mechanical stress, moisture, chemical compounds(acids, gasoline, oils), is not subject to corrosion, sets and dries very quickly, and is easy to paint.

It is used to join tiles, metal structures, wooden roofing details.

Work with this material can be carried out even in winter period, but it is better to refrain from using it in sunny weather: the substance deteriorates in the sun.

Advantages and disadvantages of different sealants

Each type of sealant has its own characteristics. For the right choice you need to know their pros and cons.

Silicone sealants

Advantages:

• resistant to precipitation and ultraviolet irradiation;
• have high resistance to the development of mold and fungi;
• have high level adhesion to most building materials;
• provided wide choose color range.

Flaws:

• cannot be used on a wet surface;
• cannot be used when working with plastic (polycarbonate, polypropylene, fluoroplastic, polyethylene);
• incompatible with simple dyes.

Bitumen sealants

Advantages:

• have a high level of resistance to low temperatures;
• can be used when working with any materials;
• used on both dry and wet surfaces;
• affordable.

Flaws:

• unstable to high temperatures;
• Available in only one color – black.

Acrylic sealants

Advantages:

• have superadhesion to porous surfaces;
• do not contain solvents;
• have no odor;
• presented in a wide range of colors;
• have moisture-resistant variety, which can be used for roof sealing work;
• can be painted or varnished after hardening.

Flaws:

• Before starting work, the surface to be treated must be perfectly dry;
• in the cold season with negative temperatures Some difficulties may arise.

Polyurethane sealants

Advantages:

• have excellent adhesion to any building materials;
• resistant to corrosion;
• do not deteriorate under the influence of ultraviolet irradiation;
• are not subject to destruction under the influence of acids, alkalis, salts;
• set quickly;
• do not flow down the surface;
• maintain volume;
• easy to paint.

Flaws:

• content harmful substances(not very significant, since the sealant is used for external work);
• high price (due to the quality of the material, it is completely justified and quickly pays for itself).

Features of working with sealant

Work on sealing joints, junctions, deformed seams using different types sealants must be carried out according to certain rules.

• First you need to prepare the surfaces.

To do this, they must be cleaned of dust, dirt, solution residues or old sealant layer.

When carrying out work in winter time the surface is cleared of snow, ice and frost. This can be done using an electric brush and manually. To obtain an even seam, you can stick a special tape on the outer edges of the surface, which is removed after completion of the work.

If it is necessary to have very high-quality adhesion of the sealant to the joint surface, it is necessary to prime the inner edges of the seam using a primer. During surface preparation, its cleanliness can be considered satisfactory if the applied test portion of the sealant adheres to the surface being treated. It should not curl under the spatula.

• Very often, when carrying out roof sealing work, it becomes necessary to create an elastic base on which mastic will be applied.

• The sealant should be applied to the mouths of the joints of the surfaces to be sealed, and sealing anti-adhesive gaskets are used. They provide additional thermal insulation and reduce the amount of material consumed in the seam.

With a significant depth of seams, such gaskets act as depth limiters and allow you to create seams of the required depth and width, which allows you to use much more less material. In most cases, polyethylene foam and polyurethane foam bundles are used as gaskets.

The gasket installed at the mouth of the joints must be compressed by 20–30% of the initial diameter. For this reason, it is recommended to buy gaskets different diameters taking into account the likely variation in the width of the joint gaps during the installation of prefabricated parts.

• The sealing gaskets are placed along a continuous line, without gaps (breaks).

In order not to damage the surface of the gasket, it must be wound in without force, using a rounded wooden spatula.

The connection of the gaskets is made along the length of the mustache. To do this, use adhesive cloth or polyethylene. insulating tape, and the connection point must be at least 30 cm from the intersection of the vertical and horizontal joints. The orifice must be thoroughly cleaned before installing the gaskets.

Working with sealant has its own characteristics in terms of proper preparation the material itself.

One-component sealants are produced ready for use.

As for two-component mastics, their ingredients - the bulk and the hardener - must be mixed, while strictly observing the weight proportions and the sequence specified in the instructions.

Before starting to prepare the substance, you must make sure that the delivery set corresponds to that specified in the instructions. Both components are combined - they are packaged in the required ratio and are ready for mixing. The container for mixing is the container of the main component.

The quality characteristics of the sealant, which will manifest themselves during operation, depend on the quality of the ingredients.

Mixing the components can be done using a special electric tool. In this case, care must be taken to ensure that the hardener does not splash.

When using a drill, you should choose a model with adjustable rotation speed and a spiral stirrer. Its power should be 0.6-0.8 kW. A standard package is mixed in approximately 15 minutes.

The finished mass must have a homogeneous structure and uniform color; there should be no visible inclusions in it. To achieve this state of the substance, stirring is carried out in the direction from the center and edges, then back, then from bottom to top and vice versa.

It is necessary to remember that the viscosity of the sealant increases under the influence of low temperatures, so it is better to store and mix the components in a heated room.

The sealant cannot be diluted with a solvent, since this may introduce so-called curing inhibitors into the substance, which lead to a disruption of the composition and a change in the properties of the finished mastic. In particular, the sealant may lose thixotropy, which will lead to the appearance of cracks during operation.

Another feature of working with sealing materials is that they cannot be used on ice-covered, frost-covered surfaces, on insufficiently hardened and dried concrete, or at temperatures below minus 25 degrees.

The most stringent requirements apply to outdoor work: sealing the roof covering, its elements, joints, external walls, since the operating conditions in these cases are the most difficult. Sealing of joints is carried out either during installation or after its completion.

Very often sealing is required during repair and restoration work. Depending on the depth of the seam, two technologies are used for sealing: surface and filling.

The use of surface technology is advisable at depth expansion joint no more than 0.5 cm. In other cases, casting technology is used: with it, sealing is carried out using anti-adhesive gaskets.

The mastic prepared in advance is applied to the surfaces to be joined using a syringe gun or spatula: they are best used when working with deep and narrow seams.

Even in the thinnest areas, the thickness of the sealant layer should be at least 4 mm. The substance is applied evenly at the mouths of all joints. We must ensure that there are no breaks, sagging or voids.

The surface of the already applied sealant must be leveled using a special tool made taking into account a certain shape the outer surface of the seam and its width. You can also use a regular spatula. To prevent the sealant from sticking to the tool, it should be pre-wetted with soapy water.

Each type of sealant has its own characteristics, which also need to be taken into account when carrying out work. So, silicone sealant sets in 30 minutes. The rate of its complete polymerization is determined by the thickness of the seam. This material can be worked in a fairly wide temperature range - from plus 50 to minus 20 degrees.

Acrylic sealant completely polymerizes in 21 days. It takes 20 minutes for it to set. Adhesion should be checked within one hour.

Polyurethane sealant polymerizes in 14 days. It sets in 1.5 hours. If the seam is damaged, it can be reprocessed. During work, you must wear gloves and a respirator.

Application of bitumen sealant should be carried out in thin layers and certainly at above-zero temperatures. High-quality roof sealing will increase the time interval between major repairs.

Prices

The cost of sealant depends on specific type, technical characteristics, manufacturing company. Below are approximate prices for 300 ml packages of material:

• rubber roofing sealant – from 135 to 200 rubles;
• bitumen sealant (for metal roofing) – 196 rubles;
• polyurethane sealant for seams - from 154 to 250 rubles;
• silicone sealant - from 160 to 225 rubles.

CONCLUSIONS

• Sealant is a special substance to ensure the tightness of the roof covering, joints, and connections.
• The main qualities of the material are strength, reliability, moisture and air tightness.
• There are 4 main types of sealants: silicone, bitumen, acrylic, polyurethane.
• Each type of sealant has its pros and cons.
• For getting good result sealing must be carried out according to all rules.
• Prices for sealants depend on the specific type of substance, technical characteristics, and manufacturer.

Video instructions on how to carefully fill the seams with sealant.

When carrying out roofing repair work Often there is a need to seal cracks and crevices that have arisen in the roof during its operation. Bitumen sealants are ideal solution various “roofing” problems.

You can often encounter various types leaks, which cause a lot of discomfort and inconvenience, and you don’t always want to carry out a comprehensive replacement roofing material. For this purpose, bitumen sealants were created, which have a number of advantages that allow roof repairs to be carried out in as soon as possible and on your own.

The main advantages of bitumen sealants are good adhesion to all surfaces, resistance to water and various atmospheric influences. It should also be noted that this type of sealant is convenient to use on wet surfaces and protects the roof from rust, which contributes to the rapid destruction of materials.

Bitumen sealants are characterized by rapid drying, which ensures quick and easy repair work. The setting time of the sealant is less than half an hour, and it takes two to four hours to completely harden, however, on some surfaces, bitumen sealants can only completely harden after at least two weeks.

Correct use of bitumen sealants ensures their long service life, which ranges from 15 to 20 years. When applying sealant, the following basic rules must be followed:

• before applying bitumen sealants, the surface must be cleaned and degreased with a solvent;
• it is advisable to use sealants at positive temperatures from +5°C to +30°C;
• sealant must be applied several times thin layers, which will ensure the fastest and highest quality drying;
• the layer of sealant applied should be from 0.5 to 1 millimeter, while its average consumption on square meter should not exceed 0.8 to 1.8 kilograms;
• When using bitumen sealants on porous surfaces, these substrates should be pre-primed and wait until they dry completely.

It should be noted that bitumen sealants can be used not only for sealing roof gaps and cracks, this type sealant is successfully used to seal, seal and fill cracks in foundations, drainage systems, plinths and other surfaces.

The HERM company offers to buy sealants in small and large wholesale, which will directly affect the timely implementation of repairs and construction work, and will also allow you to significantly save money and time.

Defects in metal roofs are usually associated with leaky joints. individual elements. But due to roof leaks, considerable problems can arise that will disrupt the normal living conditions in the house and, over time, the building envelope may become unusable. For example, metal leakage pitched roof may cause rotting rafter system made of wood.

Types of roofing sealants

The reliability and strength of any roof is given by the use of special sealing pastes. For example, a sealant for a metal roof should have:

• good elasticity;
• excellent adhesion to metal surfaces;
• increased vibration resistance;
• high water-repellent characteristics;
• increased resistance to weather conditions of any type.

By type of transition to working condition The following types of materials are distinguished:

• uncured, which do not change their qualities after use. This perfect solution for sealing joints of various configurations. A non-curing metal roofing sealant that has good adhesion and is weather and water resistant. The operating temperature range while maintaining its properties is 200 degrees, ranging from -60°C to +140°C. Release form: packaged pastes or double-sided sealing tapes. The latter are quite often used to seal any type of seam joints;

• cured, changing their state either as a result of drying, that is, evaporation of liquid, or chemical reaction. According to the method of use, they differ from non-curing ones - their components are mixed immediately before the start of insulation work.

No matter how the mixing takes place - manually or on special equipment, the “life activity” of the composition does not exceed three hours.

Manufacturers and products

Choosing a sealant for a metal roof is both easy and difficult. On the one hand, quite a wide range of, on the other hand, the quality of the material is of particular importance. Considering the disastrous results that can result from using poor quality material for the roof, it is advisable to first look for them among the products famous manufacturers. Let's give just a few examples.

Titan brand sealants can be used at sub-zero temperatures, on surfaces of any orientation, including vertical. There are no restrictions on the composition of the base. High adhesion rates make it possible to do without preliminary preparation grounds. It can be used on metal, tile, wood and other surfaces. For example, Tytan Industry PU-25 is suitable for insulating seam and flat roofs.

Sazilast 51–53 is used for seam roofs. Sealing can be carried out at external temperatures ranging from -15°C to +40°C.

SOUDAL Aquafix adheres to most surfaces, including wet or underwater surfaces. Ideal for emergency repairs or other work in the rain. The product is used for metal tiles and for repairing leaks in gutters. The surface for it must first be degrease, clean from dust and dirt, the paste itself is ready for use.

Silicone sealant Ceresit, manufactured by Henkel Bautechnik, is even more resistant to extreme temperatures. After hardening, it becomes like plastic and is not elastic enough, so it does not deform at the same time as the seam.

How to work with sealant

Today, the silicone type has become especially widespread. Its use is so simple that it allows you to do everything necessary work without the involvement of professionals. As when working with any material, there are also some nuances here. For example, the condition for reliable sealing of seams is the following ratio between its depth and width - it should not be more than two to three.

Usually the depth of the seam turns out to be greater, then to adjust the parameters, a special polyethylene cord is first inserted into it.

Even if you don’t have one ready-made, you can make the cord yourself from ordinary plastic bags or bags.

A large seam width can be “corrected” by placing a strip of polyethylene on three planes.

Before using the sealing composition, the surfaces are carefully prepared: cleaned, degreased, and in some cases additionally primed.

To obtain flat surface, use a spatula with a width corresponding to the width of the seam, designed specifically for this purpose, or special leveling mixtures and sprays. It should be noted that drying time silicone sealant determines the depth and width of the seam to be filled, but, one way or another, very little time is needed for the initial hardening of the viscous mass.

Metal roof sealing technology

The seams and places where the seam fasteners are connected are sealed with polyurethane.

It is prohibited to use silicone materials for seam roofs, as they cause rust to appear on the surface of the seams.

Such work is carried out in stages. First, the surface is cleaned of dirt, including rust, degreased with a solvent and thoroughly dried. Only then is paste applied to the folded seam.

Note that it is not always convenient to use sealant in this form. Sometimes, for example, it is necessary to ensure that the paste adheres to the surface, and not the formation of a convex seam.

For corrugated roofs, for example, it is sometimes more convenient to use self-adhesive tapes with a sealing compound applied. On one side, remove the anti-adhesive coating and press the tape with the sticky side to the cleaned and grease-free joint of the sheets. If necessary, the edge is rolled with a roller.

For complex surfaces, say, places adjacent to structures facing the roof, special tapes with a corrugated surface are used.

The roof is one of the most important elements design of the entire house, since the service life of the roof, convenience and comfort of the residents will depend on the quality of its implementation. Therefore, in roofing work, only the most durable building materials are used and all requirements are met.

Repairing a roof does not always involve replacing the material from which it is made. Quite often it is necessary to efficiently and effectively seal cracks and crevices that allow moisture to enter the house. For this, as a rule, they use bitumen sealants. The main component of this material is bitumen, which does not dissolve in water and exhibits a high level of strength to a wide variety of external conditions. negative factors. For this reason, bitumen sealants are most often used on wet surfaces.

Life time seam bitumen sealant averages from 15 to 20 years. Among the main advantages of this material are such as excellent adhesion (adhesion) to the most different surfaces And building materials, elasticity, high level of moisture resistance, atmospheric phenomena, effective protection surfaces from rust, which can quickly destroy the roof.

The use of bitumen (roofing) sealants is relevant not only for roofing. The material is well suited for compaction, sealing, filling cracks in foundations, plinths, drainage system and other designs. But in order to bitumen sealant really showed his all positive properties and provided an excellent result, you need to remember some operating rules.

Before applying the sealant, the surface must be thoroughly cleaned and degreased using a solvent. It is advisable to apply sealant to cracks and crevices only at positive temperatures, in the range from +5 to +30 degrees Celsius. The sealant is usually applied in several thin layers, which ensures faster and better drying.

In order for the bium sealant to lay securely and firmly on the base of the roof, its layer should be a maximum of 0.5 to 1 millimeter. In this case, the average mastic consumption per square meter should be from 0.8 to 1.8 kilograms. Setting time of bitumen sealant is less than half an hour; complete drying usually takes 2 to 4 hours. Although, there are materials that dry completely only after at least two weeks. If bitumen sealant is used on a porous base (cement, cement-sand), then the roof surface must be primed using a bitumen primer, then wait for it to dry completely and only then begin the main sealing work.

Thanks to the use bitumen mastic manages to get a reliable monolithic roof, even the minimal risk of leakage is eliminated. This makes it possible to significantly increase the physical and mechanical properties of the roof, the duration of operation without the need for major renovation, reliability and other important properties.

You are on a portal about the renovation of apartments and houses, reading an article. You can find on our website a lot of information about design, materials for repairs, remodeling, electrical, plumbing and much more. Use the search bar or sections on the left to do this.