How to choose a waterproofing film for the roof and roof -

Если сравнивать современный рынок покрытий для крыши дома с ассортиментом хотя бы пятидесятилетней давности, становится ясно, что строительные технологии не стоят на месте, а активно совершенствуются. Сейчас в магазинах продаются долговечные и практичные кровельные материалы на любой вкус и кошелек, однако, укладывать их необходимо, строго соблюдая технологию. Waterproofing film для кровли – один из многих материалов, который теперь активно используется для монтажа крыши, а раньше прекрасно обходились без него. Поэтому неопытные мастера часто задаются вопросом, можно ли обойтись без подкладочной гидроизоляции, а если нет, то какое какую лучше выбрать. В этой статье мы расскажем о популярных гидроизоляционных материалах, используемых для возведения кровли частного дома, а также сравним их характеристики.

What is a waterproofing film?

Waterproofing film is a companion building material that is used to organize a roofing cake for almost any modern coating. It is a thin, but durable polymer fabric that does not let moisture through. It is laid over the roof truss feet for the purpose of creating a reliable hydro-barrier. This category of materials include:

1. Waterproofing films. They are made of polyethylene, which has pronounced moisture-proof properties, thereby protecting the roof of the house from leaks and condensate. Waterproofing films are characterized by lower price, lower strength and resistance to ultraviolet rays.
2. Roofing membranes. Membranes are called improved, multi-layer waterproofing films made of more resistant polymer compounds, which has an important quality for the roof construction - vapor permeability. Thanks to the funnel-shaped holes of small diameter, the membrane perfectly lets air in one direction, but does not allow water to leak, the molecules of which are larger than the oxygen molecule.

Important! Roofing membranes and waterproofing films in the form of rolls are sold, the width of the material in which is 1.5 m and its length is up to 50 meters. It is convenient to work with a canvas of such dimensions for any area and shape of a slope.

Differences film from the membrane

For inexperienced craftsmen it is often not clear how the roofing membrane differs from a waterproofing film, and which model is better to choose for arranging the roof of a private house. In addition, customers are confused with difficult to understand categories of "diffuse" and "superdiffuse". If we look into the construction terminology and etymology of these words, it turns out that the film and the membrane are practically the same. However, there are still a number of differences:

• Composition. Usually the definition of "film" refers to waterproofing materials made of polyethylene.
• Density. Membranes have greater density and weight due to the layered structure of the web or reinforcement.
• Breathability. Conventional films of polyethylene almost do not allow air, therefore they are not suitable for every roof covering.
• Mounting method. Membranes are often supplied with self-adhesive strips along the edges of the web, which facilitate the installation of the material, prevent leakage in the joints between the strips.

Professional craftsmen believe that, first of all, the membrane from the foam is distinguished by price. Since the introduction to the use of this term is a competent marketing move, forcing buyers to think that more modern waterproofing materials for the roof are more efficient or more reliable than the old ones.

Purpose

The question of using waterproofing material for arranging or not worries many masters. As an argument, opponents of the use of membranes cite what was previously well avoided without them. However, explaining why lining waterproofing appeared relatively recently is quite simple: first, materials with such qualities have not been produced before, and secondly, roofing surfaces have also qualitatively changed since then. Now, as part of the roofing pie roof waterproofing performs the following functions:

1. Leakage protection. With the loss of the integrity of the roof of the house waterproofing film for some time restrains leakage, preventing the finishing and furnishing of the roofing room from getting wet.
2. Prevent dampness of insulation. Waterproofing protects against condensation and leakage of thermal insulating material, which becomes ineffective when wet.
3. Protection against wetting the truss frame. The frame of the roof of a private house is often made of wood, which can rot when wet, so the roofing membrane is necessary to protect it from moisture.

Note! If, when equipping a cold-type roof, it is still possible to do without lining waterproofing, the warm roof, which includes thermal insulation in the roofing pie, necessarily needs a layer of waterproofing film or membrane protecting the insulation and frame from contact with water or condensate.

Criterias of choice

Modern waterproofing materials are very diverse, so choosing the right product can be difficult. Professional masters believe that you need to pay attention to the compatibility of the film or membrane with the selected roofing coating and its basic parameters. Roof film must meet the following criteria:

• The expressed water tightness. A normal indicator is water retention with a pressure of 10 MPa for 10 minutes.
• Strength. Mechanical strength is characterized by two parameters - the density and strength of the material to break.
• Resistance to temperature changes. The film must be able to withstand temperatures in the range of -40 / + 80 or more.
• Elasticity. Elastic waterproofing materials are not torn under the influence of water during leaks, because they serve longer.
• Tolerance to ultraviolet radiation. It is necessary that the material does not deteriorate under the influence of ultraviolet radiation.

Please note that the operational life of the underlay waterproofing should correspond to the service life of the roof covering of the house. If a low-quality film with a minimum service life is used in the roofing pie, then it will in a short time require replacement, which cannot be performed without removing the roofing material.

Mounting technology

There is nothing difficult in the installation technology of lining waterproofing, so you can easily perform this operation with your own hands. Attach the film to the rafters using a construction stapler or using a special adhesive composition. The mount is performed as follows:

1. The truss legs of the roof frame are installed first.
2. Then waterproofing material is cut into strips, the length of which corresponds to the length of the roof.
3. Stripes should be laid with an overlap of 10-15 cm perpendicular to the rafter legs, and then secured with a construction stapler or glue.
4. Joints can be glued using construction tape.
5. On top of the waterproofing film along the truss legs fix the laths of the contra-grills, which allow you to create a ventilation gap between it and the finishing coating.
6. The crate is fixed on the counter-lattice perpendicular to the rafters, and then the roofing is laid according to the technology recommended by the manufacturer.

It is believed that the smaller the slope of the roof, the safer should be waterproofing lining. If the slope angle of the slopes is less than 15 degrees, then the overlap between the canvases is increased to 15-20 cm, and the valley ends, the joints with the vertical surfaces, protect the film from the second layer.

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