Open basement kitchen with amber pendants and sliding doors to a sunken patio with steps up to the garden
| 4.8 42+ Reviews
Considerate Construction Scheme

Basement Conversion in Putney

Transforming your southwest London home with a tailored basement conversion in Putney requires more than standard building work.

With over a decade of award-winning craftsmanship, Proficiency Design & Build combines luxury design and structural expertise to deliver high-end basement conversions, fully tailored to your lifestyle and approved by Wandsworth Council.

Convert With Us
Furnished basement living room with broad foreground steps, straight rear-left stairs and a right-hand window to a lightwell

Rated 4.9/5 on

Fantastic builders who really care about the quality of finish.

Portrait of Oliver Meek

Oliver Meek ( Director At Rio Cinema )

The Proficiency Difference

Local
Expertise

With over 14 years of experience, we specialise in Victorian and Edwardian basement conversions across Putney and Central London. Our team expertly manages building regulations, planning permission, and construction, backed by a 4.8/5 Google rating.

Dedicated Project Management

Every basement renovation and house extension project is led by a qualified project manager who oversees every building phase from planning to completion. We strive to deliver transparent communication, meticulous building control, quality services, and complete customer satisfaction.

High-End
Finishes

We only use premium building materials and expert tradesmen to enhance the long-term property value of your Putney home, delivering luxurious, high-quality results that stand the test of time.

Experience the Difference

SW15 Basement Conversion Specialists

As trusted basement conversion builders in SW15, we help homeowners create extra space without compromising existing areas.

Working across Putney and the neighbouring Greater London surrounding areas, we handle all applications and party wall agreements through the London Borough of Wandsworth Council on your behalf.

From luxury home cinema rooms and home offices to bespoke wine cellars, guest suites, and kids' playrooms, our basement conversion company designs refined living areas in this sought-after southwest London conservation area.

Plan Your Build

Basement Conversion Process

Free Consultation

Our basement conversion contractors assess feasibility, structural constraints, and planning applications to confirm the potential of your new basement conversion.

Structural Planning & Design

Our expert architectural services produce detailed structural drawings and submit them to the Wandsworth Council for approval.

Excavation & Groundworks

All excavation and groundwork comply with local building regulations, including the installation of concrete slabs where required.

Waterproofing & Drainage

We use industry-approved Type C cavity drain membrane systems for Putney basement conversion projects to prevent damp and water ingress.

Fit-Out & Finishing

Our interior design team tailors your new basement to your vision, delivering high-end yet functional spaces.

Our Construction Company

Proficiency Design & Build is a specialist construction company delivering high-quality basement conversions throughout Putney, SW15 and Greater London.

  • Federation of Master Builders - Approved membership confirms quality work, financial stability, and adherence to industry standards.
  • Fully Insured - Comprehensive coverage, including Public Liability, Professional Indemnity, and Contractors All Risk. We are also NICEIC and Gas Safe approved.
  • Considerate Contractor Scheme - We are committed to best practice in worker wellbeing, community relations, and minimising environmental impact on every home extension project.
    • Get a Quote

Our Building Projects

The Avenue kitchen adjoining a pale-sofa living area with veined marble worktops and black-and-brass pendants
The Avenue, Queen's Park Side Return House Extension View Project
Light-filled Conewood Street kitchen renovation with a pale pink island and brass-handled cabinetry
Conewood Street, Highbury Side Kitchen Extension View Project
Kitchen interior in the Cambridge Road project with a white-topped island and timber breakfast bar
Cambridge Road, Twickenham Open Plan Kitchen Extension View Project
Open-plan kitchen at Westbere Road with a pale island worktop and herringbone timber flooring
Wesbere Road, West Hampstead Kitchen Renovation View Project

High-End Basement Conversion Services
Basement lounge refurbishment with beige seating and a wall-mounted TV, a left-hand kitchenette and curved carpeted stairs to the right

Refurb

Transform existing cellars into bright, functional rooms filled with natural light, tailored exactly to your specs and vision.

Refurb Your Basement
Blue-grey basement living area with a rectangular hopper window, dark sofa and home entertainment system

Conversion

Full basement conversions designed and built by experienced contractors, managing planning, excavation, and high-quality fit-out from start to finish.

Basement passage connecting two separate rooms and a wine cellar beneath black iron staircase railings

Cellar

Bespoke cellar conversions, including wine storage, tasting rooms, or entertainment spaces that inherently increase your property value.

Building a room

Work With Local Basement Conversion Experts

Contact Proficiency Design & Build for all your basement conversions in Putney.

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