Frequently Asked Questions

What is the difference between a cellar and a basement?

On this website the terms 'cellar' and 'basement' are used interchangeably to mean a room or collection of rooms that are located below (or partially below) ground level. In the UK the term 'cellar' tends to be used to describe residential projects while the term 'basement' is used to describe newbuild and commercial projects. However for all intents and purposes the terms 'cellar' and 'basement' can be taken to have the same meaning.
 
How much does a basement conversion cost?
The cost of a basement conversion will depend on a number of factors including:

The size of the basement
Whether it is necessary to lower the floor to provide adequate headroom
Whether underpinning is required
The condition of the basement - e.g. structural strength of floor slab, condition of walls
The proposed quality of fittings and decor in the basement
Access constraints etc...

For this reason the cost of a basement conversion can vary from as little as £10,000 for the conversion of a very small basement space to well over £100,000 for a large project involving the excavation of basement space where none previously existed (known as a 'basement dig-out').
 
How much will a basement conversion add to the value of my house?
In virtually all cases a basement conversion will add to the value of a property. However the exact increase in value will depend on a number of factors such as local property prices, the size of the basement, and the quality of fittings and decor in the basement.
 
How much does the inclusion of a basement add to the cost of a newbuild house?
Once again, it is difficult to provide exact figures. However, the cost of including a basement as a proportion of overall project cost is lowest where land costs are high and on sites with ground conditions that would require deep foundations even if a basement were not included in the design (e.g. sloping site, poor ground). A detailed cost-benefit study is available from the Basement Information Centre entitled "Basements 1 - Benefits Viability and Costs."1 The study found that a typical three bedroom house with a storey wholly below ground might cost 11.5% more than an equivalent house without a basement, while a house with a partial basement might cost just 4.1% more. Obviously, the additional cost of including a basement should be weighed up against the benefits that the inclusion of a basement provides.
 
What can I use my basement for?
Basements can be used for virtually any purpose that above-ground rooms can be used for. Popular uses in domestic properties include playrooms, gyms, swimming pools, music rooms / studios, kitchens, bathrooms, bedrooms. In commercial properties, basement areas can be used for archive storage, car parking, and retail space.