How to convert a cellar in 6 steps

Cellar conversions are a popular renovation. An increasing number of people want to know how to convert a cellar and make the most of that space. Basement conversions offer a great way to extend and renovate your existing property without cutting into your garden. Alternatively, they’re a great way to extend your square footage if you have no garden space at all.

Cellar conversions add a whole new level to your floor and can be used for a variety of purposes, such as new social spaces or bedrooms. Consequently, this often makes them better options than loft conversions. Plus, a cellar conversion adds value to your property, meaning you’re making a long-term financial investment that’ll pay off when/if you decide to sell your home.

How to convert a cellar

Cellar conversion building regulations

There are a number of steps that you must take in order to convert your cellar, but hiring a professional, or a team of professionals can help you through this process. For example, you’ll need a:

• Structural engineer
• Plumber
• Electrician
• Painter and decorator

You should check with your local authority to see whether you require planning permission, and you should also make sure your cellar can meet fire safety regulations.

Read our UK Building Regulations guide for more information.

How much to convert a cellar into a living space?

Want to know how much a cellar conversion might cost you?

• Cellar conversion cost: Most conversions average around £1,400 per square metre.
• Spiral wine cellar cost guide: Self-build kits range in price from £18,800 to £33,400 (minus installation fees)

Click on the individual links to learn more about each basement conversion and its associated costs.

How to convert a cellar into a room

Step one: Consider hiring a professional

Hiring a professional is one of the first steps you need to take. They can help you with several aspects of the process, from checking the foundations to planning out the layout of the cellar to its decor and finish.

For the best results, we recommend hiring a cellar conversion expert. When you hire one of our trusted professionals, you’re able to see their profile and view their customer reviews. Even better, those reviews are from your neighbours and checked by us to make sure they’re legitimate.

Step two: Check your waterproofing

The next aspect your need to consider is how you’re going to waterproof the area, which will affect your insurance claim (especially if you live in a flood-risk area). Waterproofing can be done in a number of ways:

• Externally waterproof it;
• Use tanking and apply fully bonded cement to the walls and floor; or
• Use cavity drain membranes to ensure water stays out of your cellar.

Step three: Work out if you need to level your flooring

Flooring is another important consideration when converting your cellar, especially if you have uneven floors. Screeding a concrete layer will render your floor more even and give you plenty of further flooring options. Read our ‘how-to screed a floor‘ guide for further information.

You could also opt for a floating timber floor, and if your cellar is particularly cold, you might want to opt for underfloor heating.

Step four: Consider your insulation and heating

Insulating your cellar not only makes your home more energy-efficient but also creates a more welcoming living space. There are many insulation options to choose from, including blanket insulation, foam board insulation, loose-fill insulation, and sprayed foam insulation.

As well as properly insulating your basement, you’ll also need to heat it. Thankfully, there are many options for this too, including underfloor heating, radiators, electric heaters, and oil heaters.

Step five: Plan your lighting

Once you’ve decided upon and installed the foundations outlined above, the penultimate consideration before decorating your newly renovated cellar is lighting. Of course, natural light is preferable. However, if you’re unable to install a window, spotlights and wall lights are great options that will light up your basement whilst maintaining the ceiling’s height.

Step six: Add the finishing touches

You can hire an interior decorator to design your new cellar for you or do it yourself with some mood boards for inspiration (and a little bit of DIY know-how!) Now you have a lovely, new space to use however you please, consider turning it into a social space, a bedroom, or even a wine cellar!

The options are endless when you convert a cellar, and you can be as creative as you please! Check out our cost to finish a basement guide to learn how much a project like this might set you back.

How to convert a damp cellar

Whether you’re converting your cellar to live in or just using it for storage, it needs to be properly waterproofed (or tanked) so your belongings don’t get damp. Waterproofing also increases the value of your home by making it more appealing to potential buyers.

The type of ground your home is built on will dictate the kind of waterproofing you need, so it’s important to work out what you want to use your basement for before you get started. Having a rough idea of the budget also helps.

Read our guide: How much does tanking cost? for a comprehensive breakdown.

FAQ

Is it worth converting a cellar?

Victorian cellar conversions or small cellar conversions are trickier to renovate because their original purpose was meant for storage. For example, in the Victorian age, homeowners used their cellars to store coal, food, and other goods. Consequently, converting these basements is only worth it if you want to use them as storage and increase your home’s value.

What do you need to do to convert a cellar?

If you just want to convert a single room, you can use a membrane lining system that can be installed in a matter of weeks. This includes digging out the sump and fitting the pumping system. Alternatively, if you want to convert or extend the cellar beneath your entire house and turn it into a livable space, you’ll need to underpin, waterproof, and insulate the existing structure, which can take several months. However, the end results are worth it.

Do you need planning permission for a cellar conversion?

If you want to convert your basement into a habitable space, you’ll need building regulations approval. However, if you’ve already renovated your cellar and you only want to make repairs or redecorate, you don’t need to check building regulations. When it comes to planning permission, it’s not usually required unless the renovation alters the external facade of your house. For example, if you add extra lighting or build a separate unit.