Roof paint : A beautiful roof with better durability
The roof is one of the most important parts of a building. It forms a strong barrier against the penetration of wind, snow and rain. Damage to the roof or roof tiles can quickly lead to thousands of dollars of damage and repair costs. One way to prevent this is to treat your roof with a roof paint or roof tile coating. The quality of your roofing system impacts your investment and assets. Roof paint does not only waterproof, protect from sun damage and prevent deterioration, but also improves the cost and energy efficiency of your building. It is additionally the least expensive way to improve the looks of the building and increase its value. The roof painting cost is also small compared to replacing a roof.
In New Zealand, liquid coatings are becoming increasingly popular for waterproofing flat roofs. But it is also a common solution for tiled roofs. Ultimately, as the roof is an important part of your building, you do not want to use any roof coating or roof painting service; when the job is well done, with the right product, roof painting is beneficial, however, a poor quality roof paint and sloppy application may turn out very costly. In this article we will outline the different types of roof coating, which is best for your needs, and where to find roof coating solutions across New Zealand.
Flat or pitched roof? How to choose the best roof paint
Roofing or roofing tiles is only worth the investment if you use the right coating. This differs per type of roof and the material of the surface or roof tiles. The environment also plays a role. Does the roof, for example, suffer from heavy wind, salt water or the full sun? There is a suitable roof coating for every roof.
Typically used for: Commercial and industrial buildings, factory buildings and barns
A major advantage of flat roofs is that they are the most advantageous in construction. There is less surface and therefore less coating needed. A danger of this type of roof is that water accumulates quickly and therefore leaks can occur.
Best flat roof coating: the best paint for a flat roof is a coating with strong water-repellent properties. For example bitumen / asphalt , rubber or a polyurea spraycoating.
Typically used for: Private houses , church buildings, farms, homes etc.
The original appearance of the roof tiles is often not intended to conceal but rather repair or embellish. A black or white opaque roof coating such as that used on flat roofs is therefore often not a good option. 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.
Best pitched roof coating: A roof coating on a flat roof is applied over the pre-existing membrane, usually asphalt or rubber.
Select the roof coating that is right for your project
Liquid roof coatings provide a seamless (“monolithic”), unbroken and smooth surface to your roof. They cure to a rubber-like waterproof membrane, which can be reinforced with additives or secondary materials for additional tensile strength or protective properties. Liquid roof coatings can be applied over most roof materials, including asphalt, concrete, metal, bitumen, felt, and more, though some may require priming. Each manufacturer and roofing contractor has their own formulation, but these are some of the basic roof coatings:
Bituminous and Modified Coatings – conventional industrial roof paint
Also known as asphalt or coal-tar pitch, bituminous coatings are highly sticky and viscous organic liquids used for waterproofing a roof. Aluminium pigments can be added for reflectivity, and the bitumen can be modified with polymers for improved physical qualities.When modified can last 10 to 20 years. Mostly used as industrial roof paint.
- 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
- Not as flexible as other coatings (unless modified), requires heat to cure
Water-based Acrylic Coatings – ideal for roof cladding private and industrial roofs
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 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.
- They are highly reflective
- UV resistant
- Cost effective
- Easy to work with
- Acrylics will lose thickness due to weathering
- Require temperatures above 10°C for application
- Typically do not perform well in water-ponding situations
Polyurethane, Polyurea, and Polymeric Coatings – alternative roof tile paints
These coatings (also referred to 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 in particular has outstanding physical properties and can resist permanent standing water conditions.
- Excellent tensile strength
- High resistance to temperatures (-40°C to 80°C),
- Stretch with the substrate
- Chemical, UV, impact and more traffic resistant than other coatings
- Good for ponding water conditions
- More expensive than acrylics
- Wear at the same rate as acrylics
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.
- Highly UV resistant
- Environmentally friendly
- Withstands ponding water
- Good weathering capabilities
- The most expensive coating option
- 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
If your project includes asbestos encapsulation, a liquid roof coating can provide you with the least difficult method of dealing with it. Attempted removal of asbestos can release the asbestosis-causing material, but with a liquid coating you can seal in the asbestos without having to disturb it, and protecting it from further interference.
Industrial roof coating and commercial roof paint services in New Zealand
Given the importance of roofing to the stability of a building, it is unsurprising that roof coating services are available from many providers across New Zealand. There are also plenty of products available for those looking to protect their shingles from the elements. Flat roof coating, however, is a specialist application job, requiring the expertise and training of professionals. We have compiled lists of contractors who operate in Auckland and Wellington but 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.
|Roof Coating Specialist||Address|
|Accredited Coatings||Mairangi Bay, Auckland 0754|
|Cowperthwaite Roof Coating||Unit G, 5 Cain Road, Penrose, Auckland|
|Kowhai Roof Coatings Limited||53A Victoria St, Onehunga Auckland 1061|
|Liquid Rubber||115B Elwood Rd Hastings, New Zealand 4172|
|Edwards & Hardy Roofing||10 Mepal Place, Papatoetoe, Auckland 2104|
|Roofing and Coating Systems Ltd||30a Goodshed Rd, Upper Hutt, Wellington 5018|
An overview of products to take on a roof paint project yourself
In New Zealand there is a whole range of waterproof 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 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! Take advantage of our 100% free quoting service by clicking the “Request a quote” button at the bottom of this article.
|Product||Roof Coating Type||Roof Type||PRICE (RRP) & THEORETICAL COVERAGE|
|Resene Summit Roof||Waterborne||Flat and vertical roofs||$153.90 – 4L (12 m² per litre)|
|Wattyl Solagard Roof Paint||Polymer||Flat and pitched roofs||$183.00 -10L (11 m² per litre)|
|Roofmax Roof Paint||Acrylic||Steel roofs||$147.00 – 10L (10 m² per litre)|
|Dulux Weathershield Roof & Trim||Acrylic||Flat||$220.00 – 10L (16 m² per litre)|