Building Basements - What to consider...

London Basement Builder

Old Basements are often coal holes with no head room, damp storage places with all the timber joists exposed and letting in cold air to the ground floor of the house. Modern basements are now excavated with new foundation underpinning and flood water and foul drainage systems installed, tanked and then fitted out to your specification. Perfect living areas.

There are three main types of basement we work on, each has it’s own considerations for property owners:

Basement Renovations

  • Ask a local estate agent to see if developing your cellar would add to the value of the house.
  • if you are renovating an existing cellar and the work is internal, you probably won’t need planning permission, but always check with your local planning authority (an external light-well will require planning)
  • Building control is a requirement and necessary as local building inspectors check the preparation of all structural works and the finished item.

Adding a Basement to an Existing Property

Communicate with your neighbours let them know what your plans are. Basements can be non-neighbour friendly, even more so if you're semi-detached, and they take time. Introduce us, we try to take that pressure away.

  • This is the most expensive of the three types of basement as it requires additional engineering and safety considerations.
  • Make sure you will redeem any outlay you make on your basement in the value of you property
  • This type of basement is normally most feasible in city centres where property values are very high.
  • High water tables and main services running beneath the property can make costs prohibitive, although most situations can be taken care of.
  • Some modern terraces and townhouses have ‘raft foundations’ so can’t be underpinned, so basements are not an option
  • You will almost certainly need planning permission
  • If you share a wall with a neighbour, you will need a party wall agreement drawn up prior to building work
  • Any new construction has to meet Building Regulations

New Builds

  • You will need to check that the plot is suitable, that it is well drained and not subject to flooding.
  • Good access for excavation work will be required. Good access can keep the price down.
  • The Architects we use are experienced in basement design and it is important to make sure that the natural light aspect is utilised wherever possible when designing your basement.
  • You will need planning permission as part of the New build. A new build is deemed to be a separate entity from an existing structure, if it is attached to an existing house it may be looked at as an extension. You will need to approach lawyers to deal with this matter.
  • Building Regulations will need to be met at various intervals in the New build process.
  • In some case’s there is an easement on VAT, check with your accountant on this point to see if you are eligible

What our Customers Say...

The attention to detail and the quality of finish on offer, has quite honestly blown me away. At every stage in this lengthy process the quality of the finished product has been extraordinary, their arduous care and attention to detail has helped to produce my ideal home.
Thomas Penn, Hackney, London

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Tel: 020 3086 8816 or 07779 062227

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create your ideal Subterranean Space