Can I have double glazing in a summerhouse?

You’re looking for a summerhouse. Not just any summerhouse – a really great summerhouse. You’ve got a wee dream of shed heaven in your head. Scents of freshly-cut grass and summer flowers. The tinkling clink of ice cubes in a glass of something cold and delicious. The gorgeous vista of your carefully-tended garden… 

…and the uncontrollable shivering of someone sitting in a shed in Scotland. Not quite so dreamy now, is it? 

Scotland is a bonnie country, but we’re not known for our warm climates, and the joy of a summerhouse might be lessened when the sunshine is hiding behind a cloud. 

That doesn’t mean you can’t live your summerhouse dream, and you might be wondering if you can install double glazing to keep things a little cosier. 

But will double glazing in a summerhouse sort out this problem? 

Our Sheddie experts here at G&M have given me the lowdown on the best ways to keep a timber building warmth in and water out.

You don’t have to be freezing, even in unpredictable Scottish weather. Instead, discover how to make the best choices to keep your garden building dream-worthy, dry and above all, warm.  By the end of this article, you’ll be fully equipped to choose a timber building that creates your dry, cosy dream instead of a cold, damp nightmare.

What do you need to consider if adding double glazing to your summerhouse?

So can you add double glazing to your summerhouse?

The simple answer is that you can put double glazing in a timber garden building, but it’s not always the solution to keeping warm and dry. 

Why not? 

Well, there are lots of factors to consider, including:

1. Materials
2. Wall thickness
3. Staying watertight
4. Construction method

So let’s look into these a little more to help you figure out if putting double-glazing in a summerhouse is the right choice for you.

1. Materials

Timber garden buildings come in all shapes, sizes and types, and getting your head around the differences between sheds, log cabins, garden rooms, barbecue cabins and summerhouses can be tricky.

Each of these buildings is used for different purposes, and they are all constructed differently. It’s great to have choices, but sometimes all that choice feels overwhelming. You’re looking for what’s best for you. So let’s talk timber. 

The first thing to consider is the type of timber used to construct your building – should you go for whitewood or redwood?

This is a crucial question if your priority is staying cosy and dry. Whitewood is more prone to warping and bending in the Scottish climate. This becomes an issue if you have double-glazing units because the window frames can become loose, which means water can get inside your cosy wee space. 

Water + warmth = mould, and nobody wants that. Summerhouses, or any type of timber building, can be constructed of either whitewood or redwood, and it’s not always obvious from adverts and websites which material is being used.

Make sure that you know what you’re paying for. The type and quality of the timber used are important whatever type of garden building you buy. Whitewood just won’t cut it in this part of the world (especially if you’re thinking about double-glazing).

2. Wall Thickness

If you want double-glazed windows in a timber building, the walls have to be thick enough to support them. Not just so they don’t fall out, but so they stay watertight.

The industry standard for uPVC and aluminium double-glazed windows is 20-28mm thick. If you want double glazing in your timber building, the walls must be just as thick. If you’re looking at a summerhouse that has walls thick enough to hold double-glazing units, then you’re not actually looking at a summerhouse at all. You’re looking at a log cabin. These are built of interlocking timber logs, which create a much thicker wall than the tongue and groove or overlapping timber cladding used in summerhouses. 

Do thicker walls mean a warmer building? Not necessarily. It all depends on how your building is made and what it’s made of.

To add to the confusion, some companies use the term “summerhouse” when they’re actually talking about log cabins. Make sure to check exactly how the building is made, and how well that construction method keeps out water.

3. Staying Watertight

Whether or not water gets into your timber building is a big deal. The only foolproof way to keep water out is to have walls made of layers of timber, insulation, a breather membrane and an internal cavity. 

However, this option means that your building is now classed as a garden room, not a summerhouse. There are several differences between a garden room and a summerhouse, the most obvious one being the price. 

Unlike summerhouses or log cabins, garden rooms are built to building standards and specifications, and while they’re so weatherproof that you can actually live in them, they cost a lot more than a summerhouse does.

The good news is that you can easily have double glazing in a garden room, and they most definitely keep you warm and dry.

But a garden room is not a summerhouse, just like a summerhouse is not a log cabin. Let’s look at some more of the differences between these building types.

4. Construction Method

Like garden rooms, log cabins also have walls thick enough to support double glazing, but make sure you do your homework. As well as the type of timber used, the way the walls are constructed plays a big part in keeping the weather out. 

Comparing log cabins to garden rooms, we see that one uses a single layer of thicker timber whereas the other uses several layers of wood and insulation. Don’t forget too that timber is a natural material that can shift in response to changes in temperature and moisture.

The interlocking tongue and groove system used for some summerhouses and the outer cladding of a garden room is more watertight than that used in log cabins and helps prevent excess shifting.  Shifting timber can lead to, you guessed it, water getting into your building, even if the building has double glazing. It can also get pretty darn draughty. 

Log cabins are great if you live in a climate that doesn’t experience too much rainfall and where the temperatures stay pretty stable throughout each season. If you don’t, shifting is going to occur, and water and cold will get in.

What about double glazing in summerhouses?

“But what about the summerhouses?” I hear you cry. “Does a summerhouse mean I’m doomed to dressing like an Arctic explorer every time I want to use my garden building?”

“What if I can’t afford a garden room?” 

Valid questions, Sheddies. Valid questions.

Summerhouses (which some companies say when they actually mean “wee log cabin”) are made of a single skin of timber.

That single layer is what stands between you and the elements. Just like any other garden building, It’s susceptible to water and cold. But we know now that double glazing isn’t going to help us with a single-skinned building. Either the walls are too thin to support double glazing, or the construction method can’t guarantee your building will be watertight. So what can you do? 

The solution to keeping warm in your summerhouse?

Insulate, mate! You can insulate a summerhouse by yourself, although if you want the floor to be insulated this has to be done when the building is installed. The cost of having a professional do it will depend on the size and shape of the summerhouse, as well as what type of insulation they use, but a good rule of thumb is 70-80% of the total cost of the building.

If like me, you’re a real cauld tattie and this still isn’t warm enough for you, you could put in a wood-burning stove, like these beauts from Carse Country Stoves. Just because it’s a timber building doesn’t mean you can’t have a fire – but make sure it’s installed properly. Or you could add electricity to your summerhouse and stay cosy with a wee heater. 

Or if you want to stay snug-as-a-bug-in-a-rug in your garden building all year round, whatever the weather, and if double glazing is really important to you, or if you want to live in the building, then a garden room is what you need.

See what I mean about choices?

Should you add double glazing to your summerhouse?

So where does all this leave you?

As you can see, the question isn’t so much about windows as it is about choosing the right type of garden building.

Do you need a summerhouse, a log cabin or a garden room?

Is double glazing even an option if you want to stay dry and mould-free?

What other factors should you consider as you prepare to choose the timber garden building of your dreams?

Choosing Your Garden Building

Don’t worry Sheddies – I’ve got your back. Together we can totally make your shed dreams a roasty-toasty reality. Go ahead and make the choice that suits you best. Here are the key things you need to know:

Gillies & Mackay have been designing, manufacturing and installing timber garden buildings for more than 30 years. We know our stuff. But the last thing we want is for you to buy a G&M building and regret your purchase. That’s why we devote so much time and energy to sheducation, sheducation, sheducation.

If you still have questions, check out our Learning Centre or ask away using the contact form below.