Single-storey extensions · Northolt

Single-storey extensions in Northolt

Our single-storey extensions service covers Northolt and the rest of London. You get a fixed price in writing for the agreed specification, and one person co-ordinating the trades.

Covering Northolt

Our coverage around Northolt (UB5) also includes Greenford (1 miles to the south) and Harrow.

Homes in London

Much of London’s housing is Victorian and Edwardian terraces, which is why side return extensions, rear dormers and mansards are so common. Many streets are in conservation areas, and several boroughs use Article 4 directions that remove some permitted development rights.

What is included in a single-storey extension in Northolt?

We design the extension around how you use the house: where the light comes from, how the new room joins the old one, and what happens to the drains and the garden. The structure is built in brick or block to match the house, finished with a flat roof and lantern or a pitched roof, then insulated, plastered and handed back ready to decorate.

  • Measured survey and design drawings
  • Building control application and inspections
  • Foundations, drainage and structural steel

How much does a single-storey extension cost in Northolt?

Use these ranges to budget for single-storey extensions; the survey turns them into a fixed price for the agreed specification.

Single-storey extensionsGuide price incl. VAT
Standard specification£2,600 to £3,000 per m²
Good specification£3,000 to £3,500 per m²
High specification£3,500 to £4,000 per m²

How is a single-storey extension approved in Northolt?

English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.

In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary. Deeper extensions, up to 6 m or 8 m, need prior approval from the council first.

What can change the price or programme?

  • Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.
  • Kitchens and doors have long lead times, so we order them early.

From first call to completion

  1. Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
  2. Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
  3. Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
  4. We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

Single-storey extensions: common questions

How much does a single-storey extension cost?

Most single-storey extensions cost about £2,600 to £4,000 per square metre including VAT, depending on specification, glazing and ground conditions. We give a fixed price in writing for the agreed specification after the survey.

Can we stay in the house during the build?

Usually yes. We keep the existing house closed off from the works until the knock-through near the end, and agree a temporary kitchen set-up with you if the kitchen is affected.

Who deals with the council for a project in Northolt?

We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.

Single-storey extensions near Northolt

Learn more about single-storey extensions, or see every project we cover in Northolt.

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