Natural Movement of Timber

What happens to your wooden shed or summerhouse in a hot summer?

Timber is a natural product and will expand in wet or damp conditions when it absorbs moisture. This moisture then evaporates in warm and dry conditions.

It is spring and you have just built your lovely new shed, of which you are very proud. The shed sits proudly in the garden with its gleaming new coat of wood protector.

You visit the shed every day, like a child with a new toy and you are particulary pleased with it because you have assembled it with your own hands.

Then the hot weather comes, so you take out the bbq as well as the garden furniture stored there.

Sitting one weekend with a glass of wine in one hand or a glass of beer in the other admiring your lovely shed, clank! you drop your glass because you suddenly realise there's a big gap in the side wall of your shed. You run into the shed to examine it inside. You are suddenly sweating buckets and because it is so hot you rush out of the shed again for some fresh air.

Your lovely new shed is ruined. Whoa, hang on here; let's look at what has happened. You have taken your garden furniture out of the shed to enjoy the great weather. You've been mowing your lawn less often because the grass is too dry to grow and there is no need to use any tools stored in the shed because it is too hot.

So you've had no reason to enter your shed for a week or so. The windows have been tightly closed, the door has been shut and it is hot outside. The inside of your shed has become hotter and hotter; probably well over 120F when the sun is at its highest point so the inside is like an oven. The moisture from the timber has rapidly evaporated and the timber has started to shrink. This really does happen to timber. Have you ever noticed that sometimes doors in your home become difficult to close during the winter, but open very easily during the summer months? This is down to the timber expanding with moisture content and contracting when the moisture content evaporates. The same thing happens to your shed.

So how do you stop this happening? When it becomes very hot, open a window or door to help get air inside, thereby reducing the inside temperature. This next suggestion may seem strange, but it works. Put a bucket of water inside the shed so the timber takes in moisture again and prevents excess shrinkage. Your shed is not ruined because the boards usually expand back into place with the return of wet, damp weather.

Remember your shed is made from timber which expands and shrinks naturally. Although tolerances are built in when manufactured, sometimes the hot weather pushes those tolerances over and beyond its limits. It is not a manufacturing fault but just the way timber reacts to the British weather.