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Why black exterior doors are often advised against and how to overcome potential heat issues

Selecting black paint for an exterior door may seem like a durable, hard-wearing colour choice, but actually many industry experts advise against using it.

In this blog, we’ll explore why and how to overcome potential heat issues that arise when using black paint:

Reasons why black exterior doors are often advised against

Causes damage to the door

Black paint absorbs more UV rays than lighter colours, by absorbing heat each day, the door will become hotter than it should, causing the exterior door to shrink and swell. The timber may crack, split or warp until it no longer fits in the frame properly.

Low Light Reflective Value (LRV)

Black paint has a Light Reflective Value (LRV) of 0%, it does not reflect, it absorbs light. Most paint manufacturers include this number on the tin, or on their website, it is often advised for an external door you should aim for 55% LRV or higher. The higher the paint is on the LRV index the more light it will reflect and the less likely it is to cause the door to crack or warp.

 Voids the warranty

The door frame may even warp in reaction to the swelling door and will unfortunately void the warranty on your door.

Deteriorates faster

Black paint, especially with a high gloss finish makes small imperfections highly visible and fades over time when exposed to sunlight. A light coloured timber door would endure years of wear, but once a dark paint or stain is applied it deteriorates faster. It will be worse if your door faces South and has no protection or cover from the sun.

Unsafe for use

If the black paint absorbs too much sun, it will split and damage your front door, making it unsafe for use.

Use an Anti-Heat Additive to overcome heat issues

Although black exterior doors are often advised against as the build up of heat can damage the door and surrounding frame, using a solution that reduces the build up of heat overcomes this issue and gives users clear benefits over standard black paint.

Zobel Anti-Heat can reduce the temperature up to 20℃ when applied to wooden components, for substrates with Zobel’s ZowoTec coating systems for doors and DecoTec coating systems for garden houses and log cabins.

How does Anti-Heat work?

Zobel Anti-Heat reflects IR radiation, which is not visible by humans but is found in sunlight alongside UV. IR radiation does not affect colour tone, but is absorbed by the object and converted into heat.

By preventing IR radiation absorption, Zobel Anti-Heat avoids the build up of heat and makes using black paint safe and reliable. It does not only work with black colour tones, but also reduces surface temperatures of up to 20℃ for dark tones of green, blue, grey and red.

Benefits of Zobel Anti-Heat

Reduces energy consumption and costs

Using Zobel Anti-Heat helps to save energy, as buildings with intense heat build up need to be cooled with costly air conditioning units with a high energy consumption. Using Zobel’s coating with reduced heat absorption qualities saves energy and money.

Requires less maintenance

By using Zobel Anti-Heat the wood coating is able to withstand more stress, so less maintenance is required. It also reduces the risk of resin escaping from resinous woods for an outstanding finish.

At Redwood we combine the highest quality Anti-Heat additive solutions with technical expertise. Contact us on 023 9223 3310 or email