Insulating a shed can be very inexpensive and very effective at the same time. Just a small initial outlay can save hundreds of pounds in additional heating bills as well as hundreds of pounds connecting your mains electric supply to a distant outbuilding. Combine insulating a shed with the use of solar panels on the shed roof and your building can be an economical and environmentally friendly structure.

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solar-panelsTable of contents:

  1. What do you need to know before you insulate a shed?
  2. How do you insulate a shed?

Key questions to answer before insulating a shed

Below are four key questions that will affect the outcome of your shed insulation project. Answer them to the best detail you know and you’ll be able to make an informed decision on what needs to be done to ensure your shed insulation is effective.

1. Are the windows and doors of the shed intact?

After years of use or a particularly stormy winter, sheds can be left in a state of disarray. It’s important to check, before planning a shed insulation project, that the windows and doors of the structure are intact. There’s no point in insulating the structure if the windows are compromised as the effect of the insulation will be automatically lost.

2. Are there any leaks in the roof or the floor?

Pay attention to corners and to overlaps of roofing or flooring materials to ensure no leaks are compromising the structure of the shed. If shed insulation becomes damp it can spread mould and decay timber as well as negate any positive effect the insulation has on energy efficiency and warmth.

3. Are there any gaps in the cladding?

Seal gaps in the cladding of the shed with a moisture-resistant and weatherproof sealant. Just a standard tube from any builders or construction merchant should do the job. This will bolster the effect of the insulation and make sure that the shed is even more impervious to damp and condensation.

4. What is the shed being used for?

If you’re insulating a shed for use as a home office or cosy garden building, then it’s worth installing a breather membrane between the shed walls and the insulation to help with moisture. This is especially necessary if there is no other ventilation in the shed (e.g. a roof vent). Humans naturally create moisture in the area they are in so turning a shed into a home office or garden building without a breather membrane can result in a build-up of moisture which will create damp and condensation problems.

Our top tip for insulating a shed

The goal for insulating a shed for use as a garden building or other ‘warm’ use is to make the structure better at retaining heat. Once this has been done the structure is cheaper to heat and more energy efficient.

So how do I insulate a shed?

Most domestic sheds in the UK have stripped back internal timber walls such as the ones to the right, minus the insulation slab. The exposed joists make it easy to insulate for DIYers as there are just a few steps and there’s little structural work needed. If the joists are equal distance apart then insulation slab is your best bet for insulating a shed.


The insulation slab can be friction-fit (pushed in to fit the width of the joists) with very little effort, and you don’t need to secure them so it’s an easy one-person task. Before doing this though you must consider installing a breather membrane suited to timber frame walls for ventilation. Install the breather membrane and then the insulation. Once the insulation is fit into the joists all you need to do is fix OSB or plywood board over the insulation to hide it from view and finish off the project.

General-Purpose-Sealant timber-frame-permeable-breather-membranes insulation slab Plywood-OSB-Board

Insulating a shed with natural insulation

Insulating a shed is eco-friendly and environmentally conscious in its nature but there are specific products you could use to make your project even greener. Naturally occurring insulation products like sheep’s wool insulation offer not only good thermal insulation properties but moisture-wicking properties too. You wouldn’t need to install a breather membrane with sheep’s wool insulation.

Natural insulation boards and insulation batts – such as woodfibre insulation – can also make insulating a shed greener. The sustainable wood boards can be cut to size to fit into the internal shed joists and the wood fibre insulation batts can be installed as friction-fit slabs.

Insulating a shed floor

Insulating a shed floor will always reduce the internal height of the shed as you must layer insulating products above the already existing floor. It’s worth doing though as a lot of heat will escape through the floor, especially in the winter months. To insulate a shed floor you can lay a thin layer of insulation board and top it off with OSB or plywood to stabilise the floor surface and protect the insulation.

sheeps-wool woodfibre-batts insulation board Plywood-OSB-Board








For more advice or help on how to insulate a shed or which products to use, contact us on 01752 692 206 or use our live chat feature in the bottom right to be put in contact with an expert as soon as possible.

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