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Spray Foam Insulation

Spray Foam For Garden Sheds: The Essential Guide


Garden sheds have risen in popularity over the last few years, with many using them for much more than just storing garden tools and bikes. The humble garden shed has become a Man Cave, a garden room, a pub at the end of the garden-and even a hobby room!

But would your garden shed be up to it? With holes, damp, creepy crawlies and structural issues – most garden sheds need to be insulated and improved before you want to spend any time in there.

Using spray foam insulation is one of the best ways to achieve this easily and with great cosmetic results. Read on to find out how…

Why Are Sheds Proving So Popular?

The shed paint company Cuprinol (sponsor the “Shed of the Year” competition run by Channel 4), recently revealed that they have seen a surge in entrants from people who are using their garden shed to make additional income.

In fact, this year’s winner made an impressive £5,000 per year from carrying out their hobby inside their shed.

Shed owners are using their sheds to write the next best seller, to create artwork, to build children’s toys, or simply as a space to relax and think about their money-making schemes in. But being warm, dry and comfortable is essential if you want your shed to be conducive to work or rest.


This year's 'Shed Of The Year' winner made an impressive £5000 per year from carrying out their hobby inside their shed-and you could do too!

Why Should I Insulate My Garden Shed?

Most garden sheds are the flat pack variety that we can buy at DIY stores. They are inexpensive panel structures, usually made from softwoods and are simply slotted together on a concrete or paving slab base.

The roof is generally a plywood with a layer of black bitumen sheets or even plastic. Occasionally they might have shingles. The walls are almost always single layer although you can choose to add plywood to the inside to create usable walls for shelving.

The lack of insulation in a garden shed means that it can suffer from all kinds of issues:

 Condensation: Any change in temperature will result in condensation building up inside your shed. This will result in water dripping onto your stored items, and general mould and damp developing on the timbers. Eventually, the timber will begin to rot, and you will need to replace your shed. Painting it can protect the wood, but this will need to be an ongoing job.
 Damage: The inside of the shed will be damp without insulation, and, therefore, your stored items will become damaged over time. This is especially the case for soft furnishings; if you have a sofa, chair or even a daybed inside your shed, you need it to be insulated. The electrics can also be damaged by any water.
● Temperature: Any space that is not insulated will be cold in the Winter, and hot in the Summer. The aim of insulation is to regulate temperature, and to ensure that it retains heat when needed.


Without adequate insulation in place, sheds can be a hotspot for condensation and damp, leading to speckles of mould on soft furnishings

Shed Insulation: Why Spray Foam Does It Better

The one thing you will notice about your new shed, after you have built it, is that there are places where you have gaps and even where you might be able to see the outside. This isn’t because of your poor DIY skill, it is the nature of a flat pack structure.

It is assumed that the shed will be used for garden storage and therefore this type of structure is adequate. These holes and gaps can be difficult to close with normal insulation such as mineral wool. There will be gaps that will allow the insulation to become wet. What you need is something that will close all holes.

Spray foam is perfect to use as both a hole filler and a general insulator. The process of insulating your shed will go something like this:

● Build your shed to the manufacturer’s instructions on a base that is lifted off the ground where possible. Using a concrete base or a paving slabs is a good idea.
● Once complete, use a spray foam with a small nozzle to fill all the obvious gaps. This will include the joins where the corners meet, and the underside of the roof. Around the windows is also an important place to check for gaps.
● You can then get an expert in to apply the insulation part of the process. Spray foam insulation needs to be applied by an expert as it contains chemicals that need to be carefully mixed and left to harden before they become stable. The contractor will spray the foam between the roof rafters, and in the gaps between the wall struts. It will then be trimmed so it is flush to the wall.
● You can then add plasterboard or plywood to give the room a finished look, before finishing the procedure by painting. As a result, your shed will be warmer and more usable all year round.


For UK properties, space is at a premium. By insulating with spray foam, you can transform your shed into an additional room-in less than 24 hours!

7 Primary Plus Points Of Spray Foam Shed Insulation

● Spray foam is incredibly flexible, making it perfect for awkward spaces, such as in a small shed.
● Spray foam will not take up any additional space. 100 mm of spray foam offers the same insulation value as 270mm of mineral wool insulation. You will have the head height you need, and will not lose any floor space.
● Spray foam is waterproof and even if some becomes exposed to the outside due to holes in the exterior walls, it will not become wet. Most insulation will become ineffective if it becomes soaked with water and will not easily dry out. Spray foam does not absorb water at all.
● Spray foam also offers a sound proofing quality to your shed so it can be used as a studio, or to play musical instruments in without annoying your neighbours.
● Spray foam offers some structural integrity to your shed. Closed cell spray foam is very hard and is perfect for providing additional strength to the walls and roof; however open cell spray foam will offer better insulation and breathability, as well as additional support to the structure. In essence, your shed will last much longer.
● Spray foam is entirely safe and stable once applied. As long as an expert has completed the job, you can trust that the spray foam will not release any harmful chemicals or toxins.
● Spray foam will not encourage small animals such as mice, rats or squirrels. It is not an attractive food source, and it cannot be used as nesting material. Mineral wool, however, attracts small animals due to its structure.

As you can see, spray foam is the perfect way to get the shed of your dreams. It may not win you Shed of the Year, but you might just build a place that you can disappear to when you need your own space.

In fact, you could even make a living from your shed – you just need the perfect spot to dream up the best ideas.

Set your shed up for success this Summer, with the help of spray foam insulation. Take the first step to creating a harmonious hideaway today, by calling 0800 1700 636, or by simply clicking the button below!