How To and How Often to Treat Your Garden Summer Houses
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How To Treat Your 1st Choice Summer House
There are many types of treatments available for summer houses and corner buildings, ranging from water-based treatment through to fully pressurised tanalised treatments. Years ago one of the favourite treatments was creosote, often mixed with old engine oil. This treatment did a sterling job protecting the timber from the harsh weather. This had a distinctive smell, quite strong, which tended to linger for quite a while. Not ideal if you had treated the inside of your corner building which you wanted to work in.Improved safety rules were introduced in 2003 as it had proved dangerous to use and from 30th June 2004 it is illegal even to store it or keep it in any form. A new substitute Crecote has been introduced for people who wish to get a similar effect.
A water-based preservative is commonly used on cheap summer houses, mainly serving the purpose of a base coat, for your second coat to be put on. The water is a carrier for the chemicals and helps the chemical to adhere and react to the wood of the garden summerhouse, thus protecting it to a certain degree. This can be either painted on, sprayed on, or the panels can be dipped into a bath of this treatment.
Solvent and spirit-based shed preservatives are the preferred and better method of putting treatment onto timber. The solvent again is a carrier for the chemicals and works far better than the water. The solvent or spirit helps greatly and gives better protection to the timber. Yet this can be painted on, sprayed on or dipped onto the summerhouse. Very few people dip their building in this dues to the possibility of reactions to the operatives doing the dipping.
Oil-based treatments and you are moving into the realms of ‘Rolls Royce’ types of treatment. The oil holds the chemicals and bond the chemicals into the wood. The oil soaks into the timber, giving a certain amount of ‘give’ helping with the natural movement of your corner garden summerhouse.Tanalising, or pressure-treating, is the very best you can do for your timber. The tanalising process consists of the wood being put into a sealed vat. And the Tanalith E fluid is forced into the wood under pressure.
This ensures that the preservative goes a great deal further than just brushing or spraying. The result of this is that the timber should be protected against rot for 15 years. On the Platinum corner summer building the cladding is pressure treated as standard and on the Diamond ones they are dip treated as standard. All log cabins are supplied untreated so that you can select the treatment to suit your preference.
The pressure treatment also protects against fungal and insect attacks giving your new building a long life. The appearance of the timber is quite attractive, having a light natural green tint to the wood which can blend into the garden. However, you can add a colour treatment to the wood if you wish. This treatment is ideal for any building in an enclosed space, i.e. where treating the corner summer building would prove difficult or where you like the idea of very low maintenance.
However, whatever treatment you have it is important to keep an eye on it to ensure that you retreat when necessary. The only other treatment which the tanalised summer house needs in a corner is a water repellent treatment, such as Thomsons WaterSeal. This would stop any dampness coming through if the building was subjected to torrential rain. (the timber is treated against rotting and is not a water repellent in its own right)
The water-based treated corner garden building or summerhouse should be re-treated within four weeks of delivery, ideally, and then every 2-3 years, depending on the weather conditions. The same would apply with the spirit or solvent-based treatments. With the oil-based treatment after the building has its first coat, you could get up to 4-5 years before anything needs doing again except for any sides facing into the weather.
I do not recommend any of the water-based treatments for the topcoats. I would only recommend spirit, solvent or oil-based preservatives despite what the cheap corner building manufacturers may say. Water-based treatments are fine for base coats or fences, nothing else.
Some summer houses manufacturers claim to offer a 10-year guarantee, even with the water-based treatment; however, like most things in life this is not as good an offer as it seems. There are strict conditions stating that if your corner building is not treated EVERY year, then the guarantee would be null and void. This means that the treatment they are applying only last for ONE year and further protection is coming from the treatment YOU have to apply every year. A WORTHLESS guarantee. DON’T be fooled by them. The best thing (or worse) is that you will be fortunate to find any details of the conditions on those sites.
With the benefit of my 40 years in the garden buildings business, I hope that the above advice is useful for you to understand how to get the best out of your new corner summerhouse or log cabin. Over the years there have been many improvements and changes to the treatments available, some good and some bad, however, if you look after your summer houses, they will last many many years.
Regularly oil any moving parts such as locks and door or opening window hinges.
Keep an eye on the condition of the roofing felt. If it starts to deteriorate, replace it with a good quality replacement – if water starts to seep into the roof, this is the beginning of the end for your garden building. If you are in any doubt, or would like any advice, please telephone or CONTACT US for further assistance.
Farnham Display Site – Summer Buildings
Guildford Display Site – Summerhouses
Should I Bother Treating My Summer House?
You may feel you want to put it off, but your garden summer house does need treating from time to time to give it a long life. If you follow our advice, you won’t need to do this more than every 2 or 3 years. This will ensure your garden outbuildings can be protected against everything the weather can throw at it.
Treating a building can be a messy affair, indeed, if I am doing it, so the advice is to wear old clothes which can be thrown away if too severely stained. Always bear in mind that many treatments can irritate the skin due to the chemicals in them which help to preserve the wood. But always take your time and try not to splash the treatment. If you do get any treatment on your hands, face or skin ensure you wash this off straight away.
If you have the opportunity try to treat your new building before it is assembled, certainly if it is one on the cheaper ones obtainable on the web or at your local DIY superstore as you will find the treatment they use is just like coloured water and does not give any protection to your shed. By doing this before assembly, you can ensure that all parts of the building are treated. Whilst, when assembled these parts won’t get any weather, it will not do any harm if you can do so. Always try to ensure it is liberally coated to stop moisture getting into the wood.
You will find that PAR (prepared all round) timber such as shiplap or T&G summer buildings will have a smooth finish and you can paint the treatment on very quickly. However, as the treatment will not soak in too well, it is best to use at least two coats. If your building is a feather edge or made from sawn finished timber, you will find the treatment will soak into the wood and will take longer to do. However, you will know that this treatment will last the longest due to the treatment soaking into your timbers.
You can choose to use a spray to apply treatment but, if you do, it is vital that you wear a face mask and, ideally, goggles to ensure that the fine spray does not get down your throat or on your eyes. It some instances where it is awkward to get to, such as between the fence and your summerhouse a spray is a good idea. By getting on the roof, you can reach down into the gap and liberally spray the treatment onto all exposed areas.
After you have finished treating you can take a break from these duties for, generally at least 2 or 3 years. You will find that the sides of your summer building facing into the weather, i.e. The sides which get the sun shining onto it or the rain splashing against it will need treating more often. It will become apparent by the walls fading in colour. Never wait until signs of damp start getting into the wood as this will be the beginning of the end for your garden building.
My advice is based on 40 years in the garden buildings business. For further advice about what type of treatment to use take a look at our other articles.

Hi, I'm Robin Antill, founder of 1st Choice Leisure Buildings, and I use my expertise gained over 40 years in the garden buildings industry to understand that each customer is different. With my manufacturing, retailing and customer service experience my articles help people choose their ideal shed, garden workshop, summerhouse, log cabin or garden office needs to suit their requirement and that is key to satisfaction. And what do I do when I'm not writing? You may find me following Grimsby Town Football Club or riding roller coasters - so plenty of 'ups and downs' in my life.