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Read More About How to Convert a Basement

How to Convert a Basement

Implementing plans for a basement in your house is a great way of adding space. In busy urban areas, many people have begun adding space down and started building up in order to stem issue around overcrowding. Many basements are infinitely customisable, and most offer comprehensive lighting and living solutions, so it may be an excellent choice for your home. In this article, we look at how to convert a basement and take you through the steps required to expand your property.

Why Convert a Basement?

Basements are particularly suited to urban areas and other places where a conventional extension isn’t possible. Often, there’s nowhere to go – if you own a terraced house for example there probably isn’t the space you’d need to build out back. Other than creating space, basements can also add value to a property, and depending on the area they can increase the house’s desirability enormously.

Do you Need any Permissions?

When it comes to the nuts and bolts of how to convert a basement, you need to make sure you have the right planning permissions to carry out your work. Under certain circumstances, building can be undertaken using permitted development and this will prevent the need to apply for planning permission. If you have a cellar beneath your property already, for example, and you’d like to convert it for use in your home, you should only need to apply for change of use. As always, it’s best to get proper advice from reputable sources before you start work.

Building Regulations and Next Steps

Fundamentally, there are two different types of basement. You can either use an existing cellar, or excavate underneath your home to create a new building structure to develop. However you create a basement, you will be subject to building regulations that determine the construction standards of your property. There is one exemption – if you’re renovating an existing basement that is already habitable.


When carrying out any work to your property, whether it be redecoration or major renovation, you need to have a clear idea in your mind what your budget is. When it comes to converting a basement for habitable use, small costs can add up, so it is imperative to get the advice of a trusted building or property expert before you start. If you need to excavate to make room for your basement, it goes without saying that the more ground you need to take away the more expensive the project gets.

The Construction and Waterproofing

Once you’ve got to the stage of planning, designing and costing up your basement project, you need to make sure the construction and waterproofing of it is up to scratch. This is important, and where many basement conversions can go horribly wrong.


Basement waterproofing products should be one of your primary concerns. The further down you go, the more what’s called hydrostatic pressure becomes a problem, which is essentially the pressure of moisture and water on the outside of your basement wall. Basement waterproofing is often called tanking – and it’s one of the most important steps when it comes to converting and improving the longevity of your basement.

Before you waterproof you should make sure you identify and repair any issues with the outside of the property, evaluate the ground next to your outside walls, and ensure all plants and growth from around the area is removed. If you would like any more help with this or any assistance, please do feel free to contact us here at Permagard and we’ll do everything we can to help.

Need more help with how to convert a basement? We have years of experience in basement waterproofing at Permagard. Find out more about basement waterproofing on our site.

Photos: Houzz