Step-by-Step Guide: How to Insulate Your Garden Room for Year-Round Use

DIY vs Professional Insulation: Which is the Right Choice for Your Garden Room or Office?

A question I often get regarding garden rooms is do they need insulation? This is a perfectly reasonable question as structures like garden sheds are not insulated. However, garden rooms and offices are much more than a shed – they are a fully functional structure that can be used all year round.

In this article, I explain the benefits of insulating your garden office, and give tips on how to insulate a garden room if you already have a structure and are feeling the cold a little!

Does a Garden Room Office Need to be Insulated?

Yes. If you want a quick answer, a garden office should be insulated if you intend to use it during the winter. Can you imagine sitting inside your garden shed and working for 8 hours a day when the temperature outside is 2 degrees?

Of course not! This is what it could feel like without proper insulation for your garden room or garden office. The timber structure on its own simply won’t be warm enough during the autumn and winter, and heat will be lost easily. This is why insulation is essential.

How Do You Insulate an Outside Office?

Insulated garden rooms typically have insulation in four key areas:

• Floor
• Roof
• Walls
• Windows

The floor is typically insulated via foam insulation boards together with an underlay and thick floorboards. The 100mm foam insulation board acts as a fantastic barrier between the ground and internal space and the only downside is that it reduces your vertical space a little.

The roof and walls are usually insulated using a timber frame fitted to the external walls/roof and to this, you fix various insulation items such as breathable membrane, insulation board, and acoustic insulation board. This obviously leaves an ugly wooden frame on the inside of your garden office but this is addressed with plasterboard, plastering, and painting as you would inside a house.

Insulation for windows and doors is simple – you just need double-glazed glass as opposed to cheaper single-pane fixtures. Rope caulk can also be used to seal any gaps in the doorframe and window frame fittings where heat can be lost.

How Thick Should Garden Office Insulation Be?

Aside from the insulation method, you must also give thought to the thickness. If your insulation is too thin, it won’t be effective and you could still feel the cold.

As a rule of thumb, I recommend 50mm for the walls, and 100mm for the floor. This should give plenty of insulation without cramping the interior of your garden office too much.

When looking at how to insulate a garden office, you can opt for 50mm on the floor too, but I advise going thicker as plenty of cold can seep through the floor if the office is on a concrete base, for example. The floor is the area you can afford to have thicker insulation too as you are only losing vertical space.

What is the Best Way to Insulate Exterior Walls?

The exterior walls cover the largest surface area of your garden cabin so it’s the area where the most heat is lost. As a result, insulation here needs to be tip-top.

The best way to insulate exterior walls is to create a timber frame attached to the walls. Onto this, you create layers of insulation including a moisture barrier, breathable membrane, and insulation boards (typically 50mm).

Acoustic insulation can also be included but this is optional. On the inner layer, you then have plasterboard sheets and finally finish it with plaster and paint.

What is the Cheapest Way to Insulate a Garden Room or Office?

If you have a tight budget then it is possible to create cheap insulation for your garden room but let me warn you, the method might seem a little bizarre!

The thing you can’t avoid is having a timber frame and plasterboard connected to your external garden room walls. Therefore, you can’t really save much cost here – only by choosing cheaper timber and plasterboard.

The cost-saving exercise is what you fill the space between the boards and the external wall with! In the method above, we used a range of traditional insulation techniques such as breathable membranes, and insulation boards.

However, these cost money, so what’s the alternative? Wait for it…. Old clothes and packing material! This might seem unconventional, but old or recycled clothing and packing materials like polystyrene work fantastically. You can even take a peak in your loft and see if there is any spare insulation to steal!

Insulate to Regulate – Make Sure Your Garden Room is Insulated to Year-Round Use

The great thing is that if you choose to buy a garden room, you can often pay a little extra to have it insulated. This takes away the hassle and stress of buying the insulation materials and trying to install them yourself. Either way, your garden office should be insulated so that it is comfortable to use year-long.