How to Waterproof and Insulate a Shed

How to Waterproof and Insulate a Shed

Once your shed is in place in your garden, keeping it protected from the elements is vitally important, as is preparing the interior of your shed for its intended use. Ensuring your shed is properly waterproofed and insulated should be something all shed owners think about.

Whether you’re considering doing one or both of these, our guide will provide you with some of the most important things you need to know to help keep your shed in perfect condition and protected from the elements.


How Do I Stop Water Seeping into My Wooden Shed?

Water ingress in your shed can be a real nightmare. Whether you’re using it to store garden equipment or bikes, or it’s something like a garden office, the last thing you want is water getting inside. Unfortunately, as sheds are exposed to the elements all year round, there’s a chance they may, over time, begin to leak water.

If you’ve recently bought a brand-new Power Sheds shed, good news: you won’t need to do anything (other than add some silicone around the windows) to waterproof your shed. This is thanks to our shiplap cladding, which encourages water to run downwards, polyester felt roofing and toughened glass windows. You can find out more about how our sheds are waterproofed here.

What’s the Best Way to Waterproof a Shed?

Fortunately, waterproofing your shed is a relatively straightforward process. First off, if your shed has gutters, make sure you regularly clear them. As with your house, if gutters become clogged then damp and excess water can overflow into your shed.

Look at your shed walls for any holes, which could have occurred as a result of the elements, damage from falling branches or weeds working their way into the wood. Use builder’s caulking or expanding foam to fill in any gaps and ensure water cannot get through.

Check the windows of your shed to ensure the silicone you put on when you first built your shed is still intact. Just like when you silicone your kitchen sink or bath, silicone will wear off over time. If it isn’t looking watertight, give it another application.

How to Waterproof a Shed Floor

The best place to start when it comes to waterproofing your shed floor is by ensuring you have a solid shed base and foundation in place. This will raise the shed off the ground and help avoid any seepage of water into your shed from ground level, plus it’ll allow air to circulate underneath and keep the floor of your shed dry.

All Power Sheds come with a fully boarded tongue and groove floor with pre attached floor joists which sit on the underside of the floor, lifting the shed off the base by 44mm, which will help keep your shed well elevated and dry.

Finding a Waterproof Shed Roof Covering

It’s probably quite obvious that the roof plays the most important role in keeping your shed waterproof. Most sheds will have a felt layer applied to the roof in order to do this and, as with all aspects of your shed, constant exposure to the elements may mean that damage and wear and tear occurs over time. This means that you should check your roof lining regularly and replace when signs of wear and tear or damage are showing.

Each Power Shed comes with polyester backed roofing felt which must be fitted once the shed has been built. This is specifically designed to withstand the elements and help stop water leaking into your shed.


Why Should I Insulate My Shed?

Insulating your shed is not a necessity, however, if you’re looking to use the space as an office or extension to the home it can be a good idea to install some insulation to keep the heat in and make it more comfortable for year-round use. It can also be beneficial to install insulation if your shed is used to store equipment that could be affected by extreme temperatures.

When considering whether or not to insulate your shed, consider its condition. For example, if you have an old shed that has leaks and wear and tear, adding insulation probably isn’t worth the expense. You should seek to fix these issues first before proceeding.

What’s the Best Way to Insulate a Shed?

There are several ways you can go about insulating your shed, varying from the cheap DIY options to more expensive choices. Here are some of the best ways to insulate a shed:

Celotex (PIR) Boards

Celotex boards are simply plywood insulation boards made from polyisocyanurate (PIR), which is a thermoset plastic in the form of foam. These can be easily cut to size and installed to the walls of your shed.

Bubble Wrap

A little more of a DIY method is using bubble wrap. If you’re looking for a cost-effective solution, this could be the one for you. Whilst using regular bubble wrap can be effective, we’d recommend trying foil-backed bubble wrap for extra efficiency.


Commonly used in construction, rockwool is a very efficient insulation method. It’s also great for keeping sound in (or out), so if you’re intending on enjoying music in your shed or turning it into that music studio you’ve always wanted, this could be the option for you.

How to Insulate a Shed Roof

Insulating your shed roof is relatively simply and can be done in exactly the same way as your shed walls. In fact, you won’t have to do anything differently, just continue up when you’ve done the walls to cover the entire ceiling. As heat rises, having the roof well insulated will play an important role in keeping your shed warm.

How to Insulate a Shed Floor

As mentioned above, having a properly installed shed base which allows for circulation of air and avoids damp is the best place to start here. Before you lay the wooden floor in your shed, you’ll want to use PIR boards. Just cut these down to fit in the floor cavity and underneath the joists, ensuring they lay flush and flat, then lay your floor over the top.

Having a correctly insulated floor can stop your shed from losing up to 40% of its heat, so it’s a great addition. However, it can be one of the more expensive parts of insulating your shed.


Taking proper care of your shed will help it remain in good condition for much longer, which is why upkeep, such as waterproofing and insulation, as well as painting your shed annually are so important. Whatever type of shed you have and whatever its purpose, from pent shed and apex shed to bike shed and beyond, looking after your garden building is always important.