How you own it

FreeholdLand Registry title MS571753You own the house and the land under it, so no landlord or lease has a say in what you build.

Your plot

46m²87% already built onThe land your house stands on. About 6m² of it is still open ground, and anything you build has to fit in that.

Garden depth

About 1.5mEstimated from the title planThe distance from your back wall to the end of the garden. It is what decides how far a rear extension could reach before it runs out of room.

Roof height

8.2mTo the highest point of the roofHow tall the house already is. An extension is usually judged on staying below this line, so it sets the ceiling for anything you add.

Space inside

64m²From the energy certificateThe heated floor space you have today, to measure any addition against.

Energy rating

DScored 63, checked June 2014Where the house sits on the A to G scale for running costs, A being cheapest. Certificates last ten years, so an old one is worth redoing before you sell.

Last sold for

£79,950November 2011What it changed hands for last time, from the Land Registry. A starting point when you weigh up what work would be worth doing.

Worth knowing before you plan work

• You are in a conservation area. That is an area the council protects for how it looks, so it does not stop you building — it means changes people can see, at the front, the roof and the windows, are looked at more closely, and some jobs you could otherwise just get on with will need an application.
• The plot falls in an SSSI impact zone. SSSI stands for Site of Special Scientific Interest, a protected piece of nature nearby. The zone means the council consults Natural England about large schemes; a house extension is not usually one of them.
• This is a radon area. Radon is a natural gas that rises out of the ground across much of the country. If you build a new ground floor, the builder lays a sheet barrier under it, which is a standard part of the job rather than a complication.