With SDLT through the roof, is it time to dig deep to make the most of your property?

It may not even be necessary to do much digging. If you already have a cellar this could be ripe for conversion to additional living or luxury storage space. What might you need to consider?

Building regulations

Not to be confused with planning requirements, building regulations set standards for the design and construction of buildings to ensure the safety and health of the people in them.   

A simple conversion of a basement to living accommodation would require building regulation consent to ensure that the new area meets the requirements for matters such as ventilation, ceiling height, damp proofing, and electrical wiring. The building control department of the local authority should be advised that the works are taking place. They will need to inspect on completion to issue a certificate that the works are compliant. 

Planning permission

In basic terms, planning permission is required for development which results in a change of use to a property or where works are undertaken to the exterior of a property e.g. an extension. More minor works (extensively defined in the relevant legislation) are often permitted without the requirement to obtain such permissions. These are authorised under permitted development rights. However, local authorities can elect to remove these rights from selected areas at any time.

If you are considering the creation of a basement extension of one storey only, which extends no more than three metres past the back wall of your house (as unextended), includes no lightwells or any other development visible above-ground, and arguably doesn't require "engineering works" to construct, you may have permitted development rights for your development.  This does, of course, depend on the exact specifications of your project.

Permitted development rights for basements have been a cause for concern across London in the past few years. Albeit the completed basement development may not be visible from the street, the increased construction noise, dust and traffic issues that accompany such development have given rise to real objections and push-back from neighbours and therefore, local planning authorities. Numerous authorities, including Westminster and Kensington & Chelsea, have withdrawn permitted development rights for basement developments across their boroughs. Other London local authorities, such as Wandsworth, are also considering similar action. In these areas, a full application for planning permission will always be required for any development, however small. 

Party walls

Basement excavations, more so than any other kind of extension, can elicit strong responses from the neighbours. The Party Wall Act 1996 requires that you must first serve notice on your neighbour with details of your proposals if you are carrying out works to a shared wall or within three – six metres (depending on the nature of the works) from your neighbour's foundations, whether this is digging a basement or foundations for an above-ground extension,. 

Usually a minimum of two months' notice should be given to your neighbour before you start work. The notice period will depend on the type of works proposed. If you fail to serve the necessary notice, your neighbour could apply for an injunction to stop the works. 

If your neighbour fails to respond to the notice or they do not consent to the works, surveyors must be appointed by you and by or on behalf of your neighbour to agree acceptable terms on which the works can be carried out. This is known as a "party wall award".

In most cases you would pay your neighbour's surveyor's fees and it goes without saying that you would be responsible for putting right any damage to your neighbour's property as a result of the works.

Third party consents

You may have a leasehold property, in which case you may need to seek your landlord's consent prior to carrying out any works to the property. Where this is the case, the landlord should not unreasonably withhold that consent, but this will not apply where the proposed works will be outside the premises demised by the lease.

Some leases contain a complete prohibition on any works but, if you don't ask, you don't get.  Where the works are prohibited or outside the demise of the lease, if the landlord were to agree to the works, he would be free to set his own conditions for the grant of consent. This would most likely be the payment of a premium.

Estate Management Schemes

Some areas in London are subject to Estate Management Schemes (EMS). These impose covenants on property owners similar to those contained in leases and can contain prohibitions or restrictions on alterations. If the property is within an EMS it will be important to check the terms of any such scheme carefully and ensure that you comply with them.

Onward sales

Carrying out alterations to a property without obtaining the necessary consents can not only be costly to correct but can also cause problems on any future sale or refinancing. Where there is a breach of planning or building regulation consent, for example, the local planning authority has the power to take enforcement action. They can require the payment of a substantial fine, the undertaking of further works or, in a worst case scenario, the return of the property to its former state. Any such enforcement action is registered against the local land charges register for the property, and therefore known to anyone who undertakes a review of the property. Purchasers and particularly lenders can, unsurprisingly, be put off by the risk of future enforcement action.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.