Roof coating protects your building from the elements
Roof is one of the most important parts of a building, and it accounts for some 40% of the building’s (excluding towers) exterior. It protects the interior from the seasons, wind, rain, and importantly in Qatar, sun. Your roof needs to be a solid barrier between your building and the elements; a roofing failure can lead to thousands of rials of damage and repair or replacement work. The quality of your roofing system impacts your investment and assets. One way to protect it is with roof coating.
In Qatar, elastomeric coatings are the fastest growing sector of the flat roof refurbishment market. Roof coating do not only waterproof and prevent deterioration, but also improve the cost and energy efficiency of your building by reflecting heat and reducing the need for air conditioning.
In this article we will outline the different types of roof coating, which is best for your roof, and where to find roof coating solutions in Qatar.
Roof coatings for the most common roof types
The coating type you choose for a roof project depends on the roofing material and the slope of the roof. Flat roofs and pitched roofs have different needs and there are different materials suitable for each. Windy, rainy, snow-prone or sunny environments all have different demands.
- Flat roofs: These are the most common roofs in Qatar; not only for commercial and industrial buildings but also for residential villas and towers. They are the most cost efficient roof shape because they have a smaller surface area and so need less material. The danger with flat roofs is leaking and water pooling, so the main goal in coating them is to create a waterproof barrier. A roof coating on a flat roof is applied over the pre-existing membrane, usually asphalt or rubber.
- Pitched roofs: These allow for shingles and tiling, meaning that water can easily drain and there is less risk of leaks. Tiling also has the benefit of allowing spot fixes, where fixing a leak may be a simple case of fixing the tile. When applying roof tile paint, the aim is to waterproof and provide UV protection for the tiles themselves, extending the life of the actual tiles.
Commercial & Industrial Qatari roof coating specialists
Given the importance of roofing to the stability of a building, it is unsurprising that roof coating services are available from many providers across Qatar. There are also plenty of products available for those looking for a party for painting roof shingles and protecting them from the elements. Flat roof coating, however, is a specialist application job, requiring the expertise and training of professionals. If you would like more information, or want to be connected with one of our coating partners, contact us! Our experts are here to help. Get in touch by clicking the “Request a quote” button at the bottom of this article.
The 4 basic roof coating types for optimal protection
Roof coatings provide a seamless (“monolithic”), unbroken and smooth surface to the roof. They cure to a rubber-like waterproof, UV resistant membrane, which can be reinforced with additives or secondary materials for additional tensile strength or protective properties. They can also be given properties that increase their functionality; the roof coating systems can be modified into heat reflective roof coating which keeps the inside air cooler and reduces the need for use of air conditioning. They can also be reinforced with nanotechnology to make them even easier to clean or even self cleaning.
Roof coatings can be applied over most roof materials, including asphalt, concrete, metal, bitumen, felt, and more. Each manufacturer and roof coating company has their own formulation, but these are the 4 basic roof coatings:
1. Bituminous and Modified Coatings – waterproofing roof coating
Also known as asphalt or coal-tar pitch, bituminous coatings are highly sticky and viscous organic liquids used for waterproofing roofs. Aluminium pigments can be added for reflectivity, and the bitumen can be modified with polymers for improved physical qualities.
Pros: Versatile, can be applied to asphalt. concrete, asbestos (for encapsulation), cement or metal sheeting, and built-up felt. With aluminium can deflect UV and heat from the roof.
Cons: Not as flexible as other coatings (unless modified), requires heat to cure. When modified can last 10 to 20 years. Mostly used as industrial roof paint.
2. Low VOC Acrylic Coatings – water based roof paint
This is the most cost effective liquid waterproofing system. A single component system, water-based acrylics are applied 5-10 times thicker than a house paint. Titanium dioxide (TiO2) is added to make the coating more durable and heat reflective. The white colour reduces the temperature of the roof, reflects sunlight, and so reduces the temperature of the interior and air conditioning costs. By reducing temperature and UV radiation TiO2 also protects the roof from deterioration, increasing its life. A zinc oxide additive (ZnO) can also improve reflectivity, as well as resisting mildew and algae growth.
Pros: They are highly reflective, UV resistant, cost effective, and easy to work with.
Cons: Acrylics will lose thickness due to weathering, require temperatures above 10°C for application, and typically do not perform well in water-ponding situations.
3. Polymeric, Polyurea, and Polyurethane Coatings – flexibility & UV protection
These coatings (also known as “cold liquid applied” roof coatings) are applied to a roof as a cold liquid, forming an elastomeric waterproof membrane. They are capable of stretching with the substrate without being damaged. Cold applied liquid coatings are rapid curing even in winter, have excellent adhesion to a variety of substrates, and are cost-effective. Polyurea especially has exceptional physical properties and can resist permanent standing water conditions.
Pros: Excellent tensile strength, high resistance to temperatures (-40°C to 80°C), stretch with the substrate, chemical resistant, UV resistant, more traffic and impact resistant than other coatings. Good for ponding water conditions. Can be applied on as roof tile paint.
Cons: More expensive than acrylics, wear at the same rate as acrylics.
4. Silicone Coatings – environmentally friendly roof coating
Inorganic, moisture-cured coatings made of liquid silicone. Silicone coatings can expand and contract with a substrate, providing thermal shock protection through temperature changes. Therefore suitable for metal roofs.
Pros: Highly UV resistant, elastomeric, impermeable, environmentally friendly, withstands ponding water, good weathering capabilities.
Cons: The most expensive coating option, and they lose their reflectivity over time. If the roof needs recoating it must be done with silicone or the previous silicone coating must be removed completely. Not resistant to tearing.
A small selection of roof paint products in Qatar
In Qatar there is a whole range of waterproof and UV resistant roof coatings, sealants and roof tile paints available. Whether you are looking to protect, decorate or repair your roof; there is a product to suit your needs. Keep in mind that a large elastomeric roof coating job can be difficult without proper equipment, knowledge and preparation. If you’re not sure, we’ll recommend one of our partners approved applicators to come and do it for you! Make use of our 100% free quoting service by clicking the “Request a quote” button at the bottom of this article.
|Roof coating product||Price (MSRP)||Packaging||Theoretical coverage||Roof types|
|Gardner-Gibson Sta-Kool Ultra Elastomeric Roof Coating||Rial936.00||18.9L||50-75 sq. ft. per gallon||aluminum, asphalt or tar|
|Henry Company Henry Solar-Flex||Rial 308.00||5 Gallon||100 sq. ft. per gallon||Recoating roofs previously coated with asphalt emulsion, acrylic or aluminum coatings, metal roofs|
|KST Coatings Elastomeric Roof Coating||Rial 286.00||1 Gallon||50 – 100 sq. ft. per gallon||Metal, EPDM and other single ply membranes, modified bitumen, polyurethane foam, concrete, rubber roofs and previously coated surfaces|
|Gardner-Gibson Aluma-Kote||Rial 561
|4.75 Gallon||50 sq. ft. per gallon||Aluminium roofs|
|Gaco Western GacoRoof Silicone Roof Coating||Rial 415.00||1 Gallon||100 Sq. Ft/Gallon||aged asphalt, aged EPDM, aged TPO/CPA, built-up, cap sheet, composite, concrete, fiberglass, metal, modified bitumen, torch down, sprayed polyurethane foam and most existing coatings on flat or sloped roofs|