Sealant for roofing - a material for all occasions
roofing sealant is a special viscous substance intended for roofing as well as roof repair from a variety of materials. The basis for this substance are silicone and polysulphide liquid rubbers. Sealants retain their properties in a wide range of temperatures( -55 ° C to + 80 ° C).
According to the type of substrate used, all sealants are divided into:
- acrylic sealants of this type are used to fill cracks in a variety of materials, smoothing joints in floors, walls, windows. Due to its inelasticity, it is rarely used for outdoor work;
- polyurethane are compositions that are ideal for outdoor repair work. Used for sealing and bonding metal, concrete, wood, stone, etc. Polyurethane sealant for roofing is the ideal solution to the problem of minor repairs;
- silicone sealants of this type, usually used for the installation of doorways, as well as window frames, suitable for working with glass, ceramics, wood, etc. This material has excellent resistance to UV radiation and temperature changes. In connection with the multifunctional use are: silicone heat-resistant, silicone roofing sealant, special compound for double-glazed windows, etc.
- bituminous - these sealants are resistant to all kinds of atmospheric precipitation, solvents, gasoline and oils. Used to seal joints of reinforced concrete, as well as concrete structures. It is toxic, so the area of its application is limited to outdoor work. Based on the modified bitumen, a special composition is made for the metal roofing.
Roofing Sealant - Advantages and Disadvantages of
In order to determine definitively the choice of roofing sealant, it is necessary to consider the advantages and disadvantages of different types of this material.
silicone sealants have high adhesion to all construction surfaces, show high resistance to UV radiation, as well as to fungi, mold and weathering. They are represented by a large range of colors.
It does not seem that these sealants are ideal for all occasions, but they also have drawbacks: they can not be applied to damp surfaces, can not be dyed with conventional dyes, insufficient adhesion to some plastics( polycarbonate, polypropylene, fluoroplastic, polyethylene, etc.).
Acrylic sealants have an amazing adhesion to porous surfaces, it does not contain solvents, it does not have a smell. These sealants are available in a wide range of colors. After curing, they can be varnished and painted. They are waterproof and non-weather resistant. From disadvantages: not applied to wet surfaces, demanding of temperatures and application.
Polyurethane sealant are considered the best option for roofing repairs. It has excellent adhesion, corrosion resistance, and resistance to salts, UV radiation, acids and alkalis. Do not drip over the surface, do not change the volume, easily dyed, quickly seizes. Among the shortcomings can be noted the presence in its composition of harmful, corrosive substances.
Bituminous sealants are used for sealing, sealing and filling cracks in drainage systems, roofing, chimneys, etc. Among the advantages of these sealants can be distinguished good adhesion, resistance to low temperatures, the possibility of use on wet surfaces, low cost. The disadvantages are the instability to high temperatures and the only black color of the material.
Roof sealant - principles of operation
Sealant for roofing is chosen, now it is necessary to carry out the preparatory work before the roof is sealed. The composition should be applied to a dry surface, previously cleaned from dust, dirt, grease and debris, directly from the tube or by using a special mounting gun. Seams must be filled without air gaps.
When using acrylic sealants, the film is formed 20 minutes after application. Adhesion testing time - 1h. Full polymerization of the material takes place in 21 days.
Polyurethane sealants form a film in approximately 1.5 hours, and full polymerization takes about 14 days. If the seam is damaged, it is possible to reapply the substance to the same place. It is necessary to work in gloves and a respirator.
Silicone sealants set in 30 minutes, with full polymerization directly dependent on the thickness of the applied seam. Work with this material is possible in a wide temperature range( -20 ° C to +50 ° C).
The work with bitumen sealants is carried out in thin layers and at plus temperature. That's all the features of this type of building materials.
