Garage & Basement Conversions Across London

Transform unused garage or basement into valuable living space. We create home offices, gyms, guest bedrooms, and playrooms from wasted space. We handle building regulations, insulation, heating, and all electrics throughout the conversion process.

London's Most Trusted Construction Partner

20+ Years Delivering Excellence

100+ London Projects Completed

Based on 56 Reviews

Based on 82 Reviews

Based on 108 Reviews

Book a FREE Home-Visit and Consultation

James Mitchell

Wandsworth, London | January 2025

5.0

Stopped cooking at home. 6 weeks later, hosting family dinners every weekend. Home value up £40k.

David & Michelle Chen

Hampstead, London | June 2025

5.0

Previous builder abandoned us halfway. F&F finished in 8 weeks. Daily updates. Fares treated it like his own home.

Sarah Thompson

Clapham, London | March 2025

5.0

11 weeks. Victorian terrace to dream home. Friends keep asking who did it. Already recommended to two neighbours.

Our Services

Professional Building Services in Garage & Basement Conversions

For over 22 years, Foundation and Finishing has been delivering exceptional Garage & Basement Conversions services across Greater London. Whether you're adding space with a side return, creating an open-plan kitchen-diner, or building a double-storey addition, we handle every detail from planning permission to final completion.

Garage Conversions

Transform your garage into usable living space. Popular uses include home offices, gyms, bedrooms, and playrooms. We handle insulation, heating, electrics, plastering, and flooring.

Basement Waterproofing & Tanking

Adds robust waterproofing systems to keep basements dry and structurally protected before or during conversion.

Basement Conversions

Converts basements into dry, comfortable living space, often for media rooms, bedrooms or utility areas.

Why Families Choose Us

20+ Years, Results
That Speak for
Themselves

Over 100 London families trusted us with their biggest investment. The kind of work that makes homeowners call us back for their next property.

You Decide Everything, We Handle Everything

Over 100 London families trusted us with their biggest investment. The kind of work that makes homeowners call us back for their next property.

Work That Actually Gets Done On Time

Over 100 London families trusted us with their biggest investment. The kind of work that makes homeowners call us back for their next property.

Same Team From Quote to Completion

We work with the same qualified tradespeople on every job. Gas engineers, electricians, builders, finishers. They know our standards and they deliver. One point of contact for you, zero coordination headaches.

Honest Communication

We give you realistic timelines and pricing up front. If we discover something unexpected during the work, you know immediately. No hiding problems until it's too late.

20+ Years, Results
That Speak for
Themselves

Over 100 London families trusted us with their biggest investment. The kind of work that makes homeowners call us back for their next property.

You Decide Everything, We Handle Everything

Over 100 London families trusted us with their biggest investment. The kind of work that makes homeowners call us back for their next property.

Same Team From Quote to Completion

We work with the same qualified tradespeople on every job. Gas engineers, electricians, builders, finishers. They know our standards and they deliver. One point of contact for you, zero coordination headaches.

Honest Communication

We give you realistic timelines and pricing up front. If we discover something unexpected during the work, you know immediately. No hiding problems until it's too late.

Work That Actually Gets Done On Time

Over 100 London families trusted us with their biggest investment. The kind of work that makes homeowners call us back for their next property.

Trusted Construction Services

Quality Craftsmanship & Reliability

Strong Foundations, Lasting Results

Professional & Committed Team

Trusted Construction Services

Quality Craftsmanship & Reliability

Strong Foundations, Lasting Results

Professional & Committed Team

Our Process

Simple. Straightforward. No Surprises.

Here’s exactly how we handle every project, from start to finish.

Get In Touch

Here's exactly how we handle every project, from start to finish.

We Listen & Advise

We measure everything, talk through your vision, and tell you what will actually work in your space.

Clear Quote

Fixed price. Fixed timeline. No surprises halfway through your project.

We Build It

Same team from day one to completion. Weekly progress photos. Direct line to Fares whenever you need answers.

Frequently Asked Questions

Do garage conversions need planning permission?

Most garage conversions fall under permitted development and don't need planning permission. We assess your specific situation during the free consultation.

How long does a garage conversion take?

Typical garage conversions take 4-6 weeks from start to completion, depending on the scope of work and whether services need extending from the main house.

Can any basement be converted?

Most basements can be converted with proper waterproofing and ventilation. We assess feasibility including head height, access, and drainage during your consultation.

Will converting my garage affect property value?

Converting garage to living space often adds more value than keeping it as garage storage, especially in areas where off-street parking isn't at a premium.

What about heating and insulation?

We install insulation to current building regulations and extend your heating system. Converted spaces are comfortable year-round and energy efficient.