Choosing a coating for a garage roof often becomes a dilemma between the desire to save money and the need to get a durable result. The owner is faced with a market overflowing with offers: from the usual roofing felt to modern Euro membranes. A mistake in choosing a material can lead to the fact that in two or three years the roof will again require attention, and the contents of the garage will be at risk.
In this article we will look in detail at the best way to cover a garage roof, taking into account climatic loads, budget and labor intensity of the work. You will learn about the physical properties of bituminous materials, their resistance to ultraviolet radiation and mechanical damage.
The quality of waterproofing directly affects the indoor microclimate. Dampness, dripping condensation and mold are frequent companions of an improperly installed or selected roof. So it's a matter of choice waterproofing carpet You can’t decide solely on the price per roll.
Selection criteria: what is important for a garage roof
A garage is not a residential building, but also not a simple outbuilding. Tools, spare parts, and sometimes winter supplies are often stored here. The roof must withstand snow loads in winter and not melt under the scorching sun in summer. The main enemy of bituminous materials is not water, but cyclic freezing and thawing, which destroys the structure of the canvas.
When choosing a material, first of all pay attention to basis products. It is this that determines the strength characteristics. Fiberglass and fiberglass are considered more reliable than cardboard, which was used in old GOST standards. Polyester provides the elasticity necessary to compensate for building movements.
⚠️ Attention: Do not use cardboard-based materials for flat roofs with a slope of less than 5 degrees without additional waterproofing. Cardboard quickly absorbs moisture and rots, turning into dust in 3-5 years.
The type of topping is also important. Coarse granular coating protects the bitumen layer from destruction by ultraviolet radiation. Fine-grained or dusty topping (often found in cheap analogues) serves only to prevent the layers from sticking together during storage, but does not protect from the sun.
Ruberoid: classic or relic of the past?
Traditional roofing felt has been a staple material for garages for decades. Its popularity is due to its low price and availability. However, the modern market offers improved versions that are significantly superior to their Soviet counterparts in durability.
There are several types of roofing felt, and they should not be confused. RCP (roofing with dust coating) is only suitable for base layers or temporary waterproofing. For the top layer you need RKK (with coarse sprinkles) or RCC (with colored sprinkles). The service life of ordinary roofing felt is 5-7 years, after which it requires repair.
- 🏷️ Price: The most budget option on the market, available at any hardware store.
- 📉 Elasticity: Low, cracks at subzero temperatures, requires heating during installation.
- 📅 Service life: On average 5-8 years, after which a complete re-laying is required.
Installation of roofing felt requires the use of open fire or special mastics. This creates fire safety risks, especially if the garage is located in dense buildings. In addition, the bitumen mastic used for gluing must be of high quality, otherwise bubbles will form.
Fused roofing: Stekloizol, Bikrost and analogues
If you are looking for a balance between price and quality, pay attention to materials based on fiberglass or fiberglass. People often call them “Stekloizol”, “Bikrost”, “Linokrom” or “Tehnoelast”. These are rolled bitumen-polymer materials that are fused onto the base with a gas burner.
The fiberglass base provides high tensile strength, which is critical for garages with soft roofs where walking on the roof is possible when clearing snow. Bitumen-polymer binder (CBS or APP modified bitumen) retains elasticity even in frosts down to -25°C.
The installation technology consists of heating the bottom layer with a burner until a characteristic shine appears and rolling it with a roller. It is important not to overheat the material, so as not to burn the fiberglass, and not to underheat, otherwise there will be no adhesion. Quality assembled Stekloizol lasts 15-20 years.
☑️ Preparation for fusing
Particular attention should be paid to preparing the foundation. The concrete slab must be dry and level. The presence of moisture under the carpet will lead to water boiling when heated and the formation of swellings that will burst at the first frost.
Polymer membranes: modern technologies
For those who want to forget about the problem of leaks for 30-50 years, there are polymer membranes (PVC, TPO, EPDM). These are high-tech materials that differ from bitumen analogues in the installation method and chemical composition. They do not require heating with an open fire, which makes them safe.
Membranes are installed mechanically (fastening with disc dowels) or using the ballast method (loading with stones). The seams between the sheets are welded with hot air using a special hair dryer, forming a monolithic, hermetic connection, stronger than the material itself.
| Membrane type | Base | Service life | Features |
|---|---|---|---|
| PVC | Polyester mesh | up to 30 years old | Fireproof, but afraid of oils and bitumen |
| TPO | Fiberglass/Polyester | up to 40 years old | High frost resistance, environmental friendliness |
| EPDM | Synthetic rubber | up to 50 years | Highest elasticity, difficult adhesive installation |
Despite the high cost of the material itself, PVC membranes often turn out to be more profitable in the long run. The absence of the need for heavy equipment to lift the rolls (they are lightweight) and the speed of installation compensate for the difference in price.
⚠️ Attention: When choosing a PVC membrane, make sure that there are no bitumen stains on the old roof. Bitumen reacts chemically with PVC plasticizers, destroying the material. A separating layer is required.
Liquid rubber and self-leveling roofs
If the garage roof has a complex configuration, many pipes, ventilation ducts and connections, traditional roll materials may be inconvenient to install. In this case, they come to the rescue self-leveling roofs or "liquid rubber".
This material is a two-component emulsion based on bitumen and polymers, which is applied by spraying or brushing. When it hardens, it forms a seamless elastic film that completely follows the contours of the base. This the only way to create a 100% airtight roof covering with a lot of obstructions.
Liquid rubber adheres well to concrete, metal and wood. It has no seams, which eliminates the possibility of leaks at the joints. However, the material is sensitive to the quality of base preparation and requires professional spraying equipment.
Is it possible to apply liquid rubber in winter?
Technically, some compositions allow work at low temperatures, but the humidity of the base and air should be minimal. It is better to plan such work for the warm period of the year to guarantee polymerization.
Comparative analysis: cost and durability
To finally decide what is better to cover the roof, you need to bring all the data together. Cheap material does not always mean savings if after 5 years you have to pay again for work and materials. Expensive material pays off due to the lack of repairs.
Let's consider three operating scenarios. For a temporary garage or building that is planned to be demolished in the next 5 years, roofing felt is suitable. For a permanent garage where a car and tools are stored, it is better to choose a fused roofing based on fiberglass. For a flat roof that is in use, or if the budget allows, choose membranes.
Don’t forget to take into account the cost of related materials: primer, gas mixture, fasteners. Sometimes a cheap roll requires expensive glue or complex preparation, which changes the final estimate.
Buy roofing materials with a margin of 5-7% for overlaps and trimming. Buying one additional roll later may not be profitable due to delivery costs.
Installation technology: main stages
The quality of the roof depends 80% on correct installation. Even the most expensive Technoelast It will leak if it is glued to a wet stove or if it is not heated properly. The process begins with thoroughly cleaning the base from the old coating, if it is swollen, or simply from debris.
Then apply primer (bitumen primer). It binds dust and improves grip. After the primer has dried (usually 2-4 hours), surfacing begins. You need to move smoothly, warming up the roll and the base at the same time, so that the bitumen “floats” like a roller in front of the tool.
- Cleaning and drying the base.
- Primer primer.
- Laying the first layer (lining material is often used).
- Laying the finishing layer with sprinkles.
- Sealing of junctions and funnels.
Pay special attention to junctions with parapets and pipes. Special patterns and an additional layer of waterproofing are used here. An error in these components is the most common cause of leaks.
The secret to durability is double layering. Even if you use expensive material, the combination of a lining layer and a finishing layer with topping will increase the service life of the roof by 1.5 times.
Is it possible to lay a soft roof over old roofing felt?
Technically, this is possible if the old coating is firmly in place and has no blisters or water between the layers. However, experts recommend removing the old layer in order to see the condition of the slab and not increase the load on the garage structure. Two layers of old roofing material can “lock” moisture inside, which will accelerate rotting.
What roof pitch is needed for a soft roof?
The minimum slope for deposited materials is 1.5-3 degrees (about 2-3 cm per 1 linear meter). If the roof is completely flat, it is necessary to create a slope-forming screed or use expanded clay concrete so that the water does not stagnate, but flows into funnels.
Do you need to clear your roof of snow in winter?
Modern materials (Stekloizol, Membranes) can withstand the weight of snow. However, if the layer of snow is very large, it is better to carefully remove it with a wooden shovel. The use of metal shovels is prohibited - they can easily damage the topping and break the seal.