What is the best way to protect outdoor furniture from the sun?

How does the sun damage outdoor furniture?

It would be useful to understand how the sun’s ultraviolet rays damage garden and patio furniture before deciding how to protect your valuable investment and make it last for a very long time.

The ultraviolet rays of the sun (UV) are a form of electromagnetic radiation. In other words, the rays are caused by radiant energy with wavelengths shorter than visible sunlight and microwaves, but longer than for instance X-rays. 

This electromagnetic energy produces photochemical reactions and photo-oxidation in outdoor furniture materials - particularly with organic molecules found in materials such as wood and rattan; and with synthetic molecules found in materials such as PVC and polymers - causing irreversible damage such as fading, decomposition, lifting, cracking, and hardening.

The degradation of the molecules sometimes happens even at low levels of exposure, because it is affected by factors such as humidity, temperature, wind, dust in the air, and surface dirt, all of which change the absorption of the radiant energy of the UV rays.

 

What is the most noticeable damage caused by the sun’s UV rays?

You will probably first notice fading or discolouration of your garden furniture as well as a loss of its sheen and gloss. As the degradation progresses, the material will become increasingly more brittle, with splintering, cracking, layers lifting, and ultimately structural collapse as the chairs or tables break.

 

How do the sun’s UV rays damage wooden and rattan outdoor furniture?

The UV rays cause a chemical reaction, called photo-oxidation, in the wood that destroys the cellulose and lignin in the wood and rattan. Lignin hardens and strengthens the cell walls, and without lignin, the cells and wood fibres are destroyed, causing the wood to crack, crumble, warp, and slough off layers, almost like a snake would shed its skin.

 

It is recommended that you seal the wood and rattan furniture for protection against moisture and regularly spray them with a polyurethane UV protectant to act like sunscreen while the furniture is in use.

 

How do the sun’s UV rays damage outdoor furniture made from synthetic materials?

Steel and cast-iron furniture is highly resistant to the sun’s UV rays but can still be damaged. In particular, the UV rays break down the coating and surface layers, making the furniture prone to rust and deterioration. Photo-oxidation can also bleach the metal making it lose its shine and colour. Coupled with thermal shocks (sudden temperature changes) or when the sun heats certain parts of the furniture more than another, causing the metal to expand and contract unevenly, warping the furniture out of shape.

Certain grades and untreated aluminium are vulnerable, but high-quality anodised aluminium garden furniture is highly resistant to UV exposure because they reflect most of the UV wavelengths. The paint or other coating of the aluminium will be damaged and some surface discolouring and loss of sheen will be experienced. Paste wax over the paint or other sealant on metal furniture will act as a sunscreen while the furniture is in use. Be sure to rub it in well and wipe off any remainder to ensure you don’t stain your clothes.

 

How do the sun’s UV rays damage outdoor furniture made from synthetic materials?

The most common synthetic materials used to manufacture outdoor furniture are PVC, polymers, polyethene, polypropylene, synthetic rubber, and nylon. Unfortunately, these materials are the most vulnerable to the sun’s UV rays.

The first signs of damage will be fading and discolouration, followed by the material becoming hard and brittle. The photochemical reaction between the UV rays and these synthetic materials causes small molecules to split off and the synthetic fibres degrade in a process called chain scission, resulting in structural weakness. Paste wax or plastic restorer will help prevent the PVC from drying out and will act as a sunscreen while the furniture is in use. Be sure to rub it in well to ensure you don’t stain clothes.

 

What is the best way to protect outdoor furniture against the sun’s UV rays?

You can put them in the shade, store them indoors, or apply UV protective coats, but without a doubt, the best and most convenient way to protect your garden and patio furniture is to simply cover them with the best quality covers that keep out the UV rays and which are themselves UV resistant.

 

We will consider some of the other materials from which garden furniture covers are commonly made, but please heed this advice: Only use covers that not only keep out the UV rays but are themselves UV resistant, otherwise you will be replacing the covers in a matter of months if you live in an area with high UV radiation.

Duraspell garden furniture covers have a remarkable 50UV rating, which means it keeps out 98% of the UV rays. They are manufactured from a superior woven microfibre polyester in which the manufacturers, Clearspell Ltd, have so much confidence that they have backed their covers with a 5-year guarantee, unheard of in the industry.

Not only do Duraspell covers prevent UV rays from reaching the furniture, but they also keep them dry, protect them from cold and heat, thermal shocks, wind and dust, and they keep the furniture clean. Combined, in addition to their individual benefits, together these qualities eliminate all the factors mentioned above which negatively impact the potential for damage caused by the sun.

 

Which are the most UV-resistant materials suitable for outdoor furniture covers?

Polyester

• Polyester fibres are made to be incredibly durable and can withstand many years of regular washing, extreme temperatures, strong winds or tears, and are inherently UV resistant. Woven into the microfibre pattern of Duraspell covers, they keep out 98% of the sun’s UV rays, and are 100% waterproof, but can still breathe, allowing moisture and heat which can damage your furniture, to escape

Acrylic

• Acrylic is also highly UV resistant and durable, but as a material for outdoor furniture covers it has the disadvantage that it creates static electricity, burns easily, and is harder to clean than polyester.

 Other materials used:

• Unbleached cotton contains lignins that act as UV absorbers, and silk reflects the UV radiation, but neither is as durable as synthetic covers and will not last long.

• Materials such as HDPE, PAI, and PVDF are highly UV resistant, making them good choices for furniture, but they are not soft enough to use as a fabric for outdoor furniture covers.
• Vinyl and PVC furniture covers keep the UV rays away from the furniture, but as explained under the materials used for garden furniture, they are not UV resistant themselves.
• UV-treated vinyl and PVC outdoor furniture covers will last somewhat longer, but nowhere near as long as polyester. Another disadvantage of vinyl and PVC as they are not breathable, and although they keep water out, they trap heat and moisture under the furniture covers, heightening the potential for mould and other damage.

Please check our buyer’s guide if you need help working out what size garden corner set covers you require. Click here