Single-storey extensions in Portishead

Covering Portishead

Portishead is about 35 miles north-east of Taunton. We also cover Clevedon (5 miles to the south-west), Kingswood and Chepstow.

Homes in the South West

In the South West, matching local stone, render or slate is often the main design question, and conservation areas and listed buildings are common in historic towns.

What do you get with a single-storey extension?

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
Planning or lawful development certificate where needed
First-fix and second-fix electrics, plastering and making good

What will a single-storey extension cost?

Typical ranges for single-storey extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

Single-storey extensions	Guide 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

Planning and building rules in Portishead

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.

What should I think about before starting?

Drains under the footprint may need diverting or a build-over agreement with the water company.
Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.

How does the project run?

Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

What people ask before starting

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 Portishead?

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

Other towns nearby

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