Builders – South-West London | Our Guide to Cellar and Basement Conversions

Published by Hannah King

Posted on 2 October 2019

When an ordinary extension just isn’t enough or a loft conversion is not possible, many homeowners choose to head below ground with cellar and basement conversions. It’s a great investment for space and value and an opportunity to create a dream room you don’t have. Please read on this week for our ultimate guide to cellar and basement conversions.

The Benefits of Basement Conversions

When you convert a basement you’re essentially creating a brand new livable area. It’s also a home improvement that offers flexibility, allowing the homeowner to create a space of their dreams. Most people have their own ideas as to what they’d use this new area for but some inspiring suggestions include a home gym, swimming pool and home cinema. With this mind, basement conversions can add 10 per-cent to a properties value. It’ll also speed up the process should you come to sell your home and give you years of enjoyment prior.

How Long Do They Take and How Deep Should They Be?

The depth of basement conversions depends on how they are going to be used. You may, for instance, want to keep ceiling heights low for rooms like offices and storage. In terms of a timescale, this too would depend on the end-use of your basement conversion. As a ballpark figure, you’re looking at a few weeks to several months depending on the scale.

Planning Permission and Permitted Development (PD) Rights

In terms of converting a basement that’s already existing, it’s unlikely any work will require planning permission. This is provided it’s kept a part of the property and you don’t plan on using it as a separate entity i.e. a rental flat. Major works like excavating, however, are likely to require planning permission. It’s, therefore, always best to check with your local authority on the local planning regulations. Sometimes a conversion can also be done under permitted development (PD). For this, you will need a certificate of lawful development to prove the work did not require planning permission.

Building Regulations for Basement Conversions

Before you can use your new basement your builder will need to ensure it meets building regulations. It must be deemed legally habitable through the right levels of insulation, with plenty of head height and emergency exits. After any structural work is complete a building inspector will pay a visit to sign the work off. They will also check to make sure the work hasn’t impacted the house or that of your neighbours either.

What is Damp Proofing, Tanking and Underpinning?

You may be familiar with some terminology based around basement conversions and the most common ones are damp proofing, tanking and underpinning. In terms of damp proofing, this is essentially waterproofing to stop damp entering a building’s structure and one of the most common ways of doing this right is tanking the underground space. Our team will carry out the tanking by applying a coating to the interior of the basement walls. The two methods we use are also brush-applied tanking or a cavity membrane drainage system. Underpinning for cellars basically means strengthening the foundation of an existing building so if a new basement’s required it keeps everything stable long after the excavations.

Factors Influencing Cost

Finally, we move onto cost and the factors that can influence budget. This is things like architect fees and structural engineers, not to mention the cost of the build. Then there’s the tanking for the walls, per square metre, VAT and planning charges. You’ll also need to consider site access and whether your house is located on problematic ground conditions.

Builders – South-West London for Cellar and Basement Conversions

Thank you for reading this week’s post exploring cellar and basement conversions. If you already have a cellar then you’re partway there in terms of creating a new habitable space. At Kluk Construction, we also have plenty of background transforming cellars into beautiful rooms and when you consider the options there is endless potential, ever yearned for a home gym and sauna perhaps? Then there’s games rooms, playrooms and home cinemas for cosy nights in watching movies. Please get in touch to find out more and to take your home to a deeper new level.

A bedroom basement conversion.

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