For homeowners

Extensions and refurbishments for London homes

Rear and side-return extensions, kitchens, bathrooms, bespoke joinery and whole-flat or whole-house refurbishments. We price every job line by line after a site visit, and build to your architect’s drawings or to a layout we plan with you.

One schedule for the whole house

Rear extensions, side-returns and refurbishments on London terraces

Our homeowner projects range from Victorian houses to London flats. Whatever the mix of work, it goes into one itemised schedule and one week-by-week programme.

  • Structure, services and finishes priced line by line
  • Architect, engineer, Building Control and party wall fees shown separately
  • A visible 10% contingency
Line drawing of a row of terraced houses, one with a rear extension, one with a side-return and one under refurbishment
Rear extension, side-return and refurbishment on a London terrace. Illustration

Homes

Recent home projects

All projects

Cost planner

Get a realistic range before anyone visits

Choose a project and a size. You will see the works, preliminaries, contingency, fees and VAT as separate lines.

Type of project

Measure the new internal floor area (length × width). It is shown on your architect's drawings.

Estimated total including VAT

£92,000 to £123,000

£77,000 to £102,000 before VAT

Standard finish. Choose your finish level and extras in the full planner.

See the line-by-line breakdown

Reviews

What homeowners wrote

Unedited, from our Trustpilot page.

  • Really professional service, we have ordered bespoke joinery units for my parents house, made with spray painted MDF with routed handles and also soft close drawers internally for the wardrobes. We also ordered a bespoke tv unit. Really great work, we loved it!

    ★★★★★ Elen Z. Bespoke wardrobes and TV unit Trustpilot, September 2024
  • Very professional company and great communication. Job complete in time. Highly recommended.

    ★★★★★ Alenoush G. Trustpilot, October 2024
  • Mount St Projects did a fantastic job with our property! We love our new doors and are so impressed with their service and communication. Highly Recommended!

    ★★★★★ Arman New doors Trustpilot, September 2024

Questions

Questions from homeowners

What building work do you do for homeowners in London?

Single-storey rear, side-return and wraparound extensions, kitchens, bathrooms, bespoke joinery, and full flat or house refurbishments, priced as an itemised schedule of works after a site visit.

How much does a house extension cost in London?

Our planner gives £92,000 to £123,000 for a 24 m² extension at a standard finish, including professional fees, a 10% contingency and VAT.

Do you work with my architect?

Yes. We price and build from your architect’s drawings, and show their fee, the structural engineer, Building Control and party wall costs as separate lines.

Are you members of a trade body?

Yes. Mount St Projects Ltd is a member of the Federation of Master Builders, company number 15499277.

Next step

What happens when you get in touch

  1. Tell us about the project

    Two minutes on our enquiry form, or call us. Drawings help but are not needed.

  2. We visit and measure

    We look at the property, the access, and anything that affects price: structure, services, neighbours, the landlord’s requirements.

  3. You receive a priced schedule of works

    Every line itemised, with provisional sums and exclusions stated, so you can compare it line by line with any other quote.