How to insulate a garage

Whether you’re looking to expand the amount of living space you have, or you need a dedicated home office,  insulation is key to making your garage comfortable all year round.

Many homeowners choose to improve their current property rather than move on. With increasing house prices, there’s never been a better time to start working on your own home, for example by refurbishing or converting your garage, than right now.

The first steps

The main thing to do before starting to insulate your garage is to take a step back and ensure your garage is ready to be insulated. This means giving it a good spring clean and making sure you’ve got easy access to the walls, roof, floors, and doors. This is also a good to start checking for signs of damp or other problems that may need to be addressed before work begins.

Once you have thoroughly checked over your garage, you should then check the fit of the windows and doors to see if either of them is letting in a draft. If they are, you may wish to replace them with insulated doors and double-glazed windows. This is especially important if your garage is going to become an office or new living space for your family.
Also remember to check the condition of the garage roof, which can be particularly important for garages with flat roofs, as these are more susceptible to issues such as leaks.
Checking your garage before insulating may be tedious and long-winded, but it'll save you a lot of time, money, and frustration in the future.

You should also take this time to familiarise yourself with the UK building regulations, as extensive refurbishment work on properties normally requires a raise in overall insulation performance. So, it is always worth double checking with national and local regulations before getting started.

an image of a garage wall with insulation exposed


How to insulate garage walls

Most garages in the UK have walls that are made up of just a ‘single skin’ of breeze blocks. So, for these, you have several insulation options to choose from. However, if the condition of your garage’s walls is dissatisfactory, there is the option of deconstructing them, insulating the walls, and then rebuilding the wall. This is of course expensive and could be potentially troublesome, so only attempt to do it if necessary and you feel confident undertaking the job.

Internal wall insulation

The most tried and tested method is to construct a timber frame against the inside of the walls and install insulation slabs in between the sections of the timber frame.

External wall insulation

If your property features a detached garage, it may be wiser to opt for external wall insulation. This will involve fitting  insulation boards and suitable render systems to the external walls. It may seem strange increasing the thickness of the outside of your garage, but the internal space savings could be well worth it.

How to insulate a garage roof

Choosing the right garage roof insulation for your property will largely depend on whether your garage has a pitched or a flat roof. Garages with pitched roofs can be insulated in a similar way as when fitting loft insulation in your home. When it comes to garages with flat roofs, you have the choice between constructing a warm roof or a cold roof.
Warm roof construction refers to flat roofs where the insulation materials are fitted above the roof desk. This option is generally the most recommended route to go down, as it maximises internal space by retaining your full ceiling-to-floor height, all whilst keeping your roof deck warm and reducing the risk of condensation build up.
As for cold roof construction, it is the name for flat roofs where the insulation layer is below the roof deck. They are referred to as ‘cold roofs’ due to how any area above the insulation will be colder than the living space below. If you’re opting for a cold roof, we’d suggest first screwing 50x50mm battens to the side of your rafters below the roof deck. This will ensure that you maintain an air gap of 50mm.

an image of a garage door with insulation boards


How to insulate a garage floor

Uninsulated garage floors can become incredibly cold, so underfloor insulation is a must if you want your garage to be a viable living space during the winter months. Insulation boards are a great way of achieving that warm, welcoming feeling thanks to its fantastic performance, and its thin design to ensure you’ll lose minimal space.
Once you’ve chosen the right garage floor insulation, there are a few more things to consider. If you’d like to retain the concrete slab floor of your garage, you should install a damp-proof membrane before any insulation.
As well, can also choose to insulate your garage door. Although this is optional, it makes a massive difference to the overall insulation of the garage.

Whatever your plans are, making the right choice is vital. If you’re still unsure then get in touch with our customer service team on 01472 907051, or visit your local, friendly Howarth branch. They’ll be able to talk you through the pros and cons of each option and advise you which insulation is best for your needs.

26th Jul 2022 Emily Green

Recent Posts