A leaking or swollen joint between concrete slabs roofing felt on a flat garage roof - this is a direct signal to immediately select a new coating, since ignoring the problem will lead to dampness inside the room and damage to the car. When searching for an answer to a question, what material is better for a garage roof? Roll roofing, you must immediately discard options with a cardboard base, since they will not withstand modern requirements for waterproofing and temperature changes. The modern market offers solutions based on fiberglass and polyester fabrics that guarantee tightness for decades to come.
It is a mistaken belief that any bituminous material left over from the construction of a house is suitable for a garage, because a garage roof has its own specific operation and is often subjected to mechanical stress. Correctly selected roll covering must have high elasticity to compensate for micro-movements of floor slabs, and resistance to ultraviolet radiation. In this article, we will analyze the technical characteristics of market leaders and help you determine the best choice for your case.
Criteria for choosing a durable coating
The basis for deciding whether what material is better for a garage roof? Roll roofing, is an analysis of its component composition, and not just the price segment. The key element here is the reinforcing layer, which takes on tensile loads when the base deforms. Materials based on fiberglass or polyester are significantly superior to classic cardboard counterparts in strength and service life.
The second important parameter is the type of bitumen impregnation and the presence of polymer additives. Oxidized bitumen with type modifiers APP (APP) or SBS (SBS) provides the material with the necessary properties of elasticity at low temperatures and heat resistance in summer. Without these components, the coating will become brittle in the cold or leak under the scorching sun, losing its tightness.
⚠️ Attention: The use of materials with a cardboard base (ruberoid RKK, RKP) is justified only as a temporary solution for a period of 3-5 years or as a lining layer in a multi-layer cake, but not as a finishing coating.
It is also worth considering the thickness of the protective coating. For the top layer of the roof, which will be in direct contact with the atmosphere, coarse granite or slate chips are required. It protects the bitumen layer from destruction by ultraviolet radiation and mechanical damage when walking during roof maintenance.
Comparison of popular types of rolled roofing
To understand what material is better for a garage roof? Roll roofing in your situation, you need to conduct a detailed comparison of the main types of products presented on the construction market. The best-selling materials are glass-based materials, which are divided into several categories depending on their purpose and structure.
- 🏗️ Stekloizol - a fiberglass-based material with a double-sided bitumen coating, often used for waterproofing foundations and roofs, and is characterized by high biostability.
- 🛡️ Linocrom — economy class covering made of polyester or fiberglass, suitable for laying in one layer on a prepared base or as part of a multi-layer carpet.
- 💎 Technoelast - premium material based on polyester fabric with a high polymer content, withstands extreme temperatures and has a service life of up to 25-30 years.
- 🧱 Bikrost - an economical solution for waterproofing, which requires a protective layer or installation in several layers due to the smaller thickness of the bitumen layer.
When choosing between these options, it is important to pay attention to the labeling. Letter K at the end of the name (for example, Technoelast K) indicates the presence of a coarse granule, which makes the material suitable for the top layer. Marking P means that the material has a film coating on both sides and is intended exclusively for lower layers or waterproofing.
Fused roofing technology
Most modern answers to the question what material is better for a garage roof? Roll roofing, comes down to built-up bitumen-polymer materials. The technology for their installation requires strict adherence to temperature conditions and preparation of the base. The surface must be dry, clean and treated with a bitumen primer for adhesion.
The laying process consists of heating the lower bitumen layer with a gas burner until it melts and then rolling out the roll. It is important not to overheat the material, otherwise the base may burn, and not to underheat, which will lead to a lack of adhesion. The overlap of the canvases should be at least 10 cm in width and 15 cm at the end.
☑️ Checklist for preparing for fusion
Particular attention should be paid to areas adjacent to vertical surfaces, parapets and ventilation pipes. Here, the method of inserting the material onto the vertical with mandatory fixation with a metal clamping bar is used. Ignoring this step is the most common cause of future leaks.
Polymer membranes as an alternative to bitumen
If classic bitumen solutions seem too heavy or labor-intensive to install, you should consider polymer membranes, which are gaining popularity in the garage construction segment. These materials are made on the basis PVC (polyvinyl chloride), TPO (thermoplastic olefins) or EPDM (synthetic rubber).
The main advantage of such membranes is the possibility of mechanical fastening or installation using a ballast method, which eliminates the use of open fire on the roof. This is especially true for wooden or flammable garage structures. The joints of the canvases are welded with hot air, forming a monolithic, homogeneous coating.
| Membrane type | Base | Installation method | Service life |
|---|---|---|---|
| PVC | Polyvinyl chloride | Hot air welding | Up to 20 years |
| TPO | Polypropylene and rubber | Welding / Mechanical | Up to 25 years |
| EPDM | Synthetic rubber | Adhesive / Mechanical | Up to 40 years old |
| Bitumen-polymer | Fiberglass/Polyester | Deposition | 10-15 years |
Despite their high performance characteristics, polymer membranes require special equipment for welding seams and certain skills of the installer. For smaller garage co-ops, this option may be less accessible due to the difficulty of finding qualified workers.
Secrets of saving on roofing
You can save money by using a combined method: lay the bottom layer from a cheaper material (for example, Bikrost), and the top layer from an expensive and durable one (Technoelast). This gives excellent results on a reasonable budget.
Self-leveling and painting waterproofing
In some cases, when the garage roof has a complex geometry with many obstacles, liquid rubber or bitumen-polymer mastic may be the best solution. These materials form a seamless coating that completely follows the contours of the base, which eliminates the presence of joints - potential places for leaks.
The application technology is simple: the composition is applied with a brush, roller or airless spray. However, to create a full-fledged roofing carpet, reinforcement with fiberglass mesh is required, otherwise the elastic layer may break due to thermal expansion of the slab. This method is often chosen as a repair option over the old coating.
⚠️ Attention: Application of self-leveling roofing is possible only when the air temperature is above +5°C and there is no precipitation, since moisture and cold disrupt the polymerization process of the material.
In terms of durability, high-quality mastics with UV protection can last up to 10-15 years, but they are inferior to rolled materials in mechanical strength. Walk on such a roof with caution so as not to damage the waterproofing layer.
Errors during installation and operation
Even if you identified correctly, what material is better for a garage roof? Roll roofing, violation of installation technology will reduce all advantages to nothing. The most common mistake is laying the material on a damp base. The moisture remaining under the carpet turns into steam when heated, swelling the covering and tearing it away from the base.
Another common problem is insufficient heating of the joints. If the side overlap is not heated properly, the bitumen will not fuse into a monolith, and water will gain access under the roof. You can check the quality of the seam with a special hook, trying to bend the edge of the fabric.
Tip: Before starting work, be sure to check the slope of the roof. For surfaced materials, the minimum slope should be 1-2 degrees (about 1.5-3 cm per 1 meter of length) to ensure water drainage.
Don't forget about regular maintenance. Twice a year, in spring and autumn, it is necessary to clean the roof of leaves, branches and debris. Accumulated dirt retains moisture and promotes the germination of moss, which with its roots can damage the protective layer of the roof.
Main conclusion: The optimal choice for a garage is a bitumen-polymer material based on polyester with coarse-grained topping, laid in two layers using fusion technology.
Frequently asked questions (FAQ)
Is it possible to lay a new roof directly on the old roofing felt?
This is technically possible, but not recommended. The old layer can hide blisters and moisture, which will lead to rapid failure of the new coating. It is better to dismantle the old layer or carefully prepare it by repairing all defects if dismantling is impossible.
What material to choose for a wooden garage roof?
For a wooden base, it is strictly forbidden to use fused materials with open fire. In this case, the optimal choice would be polymer membranes with mechanical fastening or lining materials on a bitumen-polymer basis, mounted on cold mastic.
How many layers of roofing should be laid on concrete?
Modern premium materials (polyester based) often allow installation in one layer. Economy class materials (based on fiberglass) require installation in at least two layers to ensure reliable waterproofing and compensate for base movements.
At what temperature can roofing be fused?
The optimal temperature range for working with bitumen-polymer materials is from +5°C to +25°C. At lower temperatures, the material becomes rigid and does not heat up well, and at too high temperatures there is a risk of bitumen overheating.