4 Moving up: A loft conversion could create a couple of extra bedrooms, a home office or a massive playroom for the children. As long as the actual volume of the house isn’t increased, and its cubic content is not exceeded by more than 50m³ in the case of a terraced house and 70m³ in any other type of house, you don’t need approval for this type of work. But before you go ahead, think about the impact it will have on your home.

“It’s important that a loft conversion doesn’t make a home unbalanced,” says Briggs. “Adding two bedrooms upstairs is great, but is there enough space downstairs to complement them? A proper staircase to the conversion is also important among buyers.”

Value added to house: 6%-15% per bedroom

Loft conversions in smaller roof spaces can be made much more useful by adding a dormer window to increase headroom and light, though there are rules governing the addition of dormers.

Value added to house: 6%-15% per bedroom

5 Single-storey extension: Increasing the size of a downstairs room such as the kitchen will increase space and add value, and you may not need planning permission to do it. The extension must not be more than 4m high and should not be within 2m of the boundary of the house. It must not exceed 50m³ in the case of a terraced house and 70m³ for any other house.

“Volume is used extensively in describing the amount that can be built without planning permission,” says planning consultant Ken Dijksman. “Remember that all such measurements are based on external dimensions and include the roof, too.”

In addition, an extension can’t be built nearer to a road than the existing house or, with other outbuildings, cover more than 50% of the garden.

Value added to house: at least 10%

6 A splashing time: Buyers decide what a house is worth, and luxury additions such as swimming pools can polarise opinions; however, a well- designed pool in the right setting is often seen as a bonus. The pool, when combined with any existing outbuilding or extensions, must not cover more than half the garden.

Value added to house: up to 5%

7 People in glass houses: Adding a well-constructed conservatory will add value to a property. However, a conservatory past its best will work against you and detract from the value of the house. You can build a good-sized conservatory without planning permission if it falls within the parameters set up for an extension.

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