JR General Building

Garage Conversions
Extra space. More value.

A garage conversion is one of the most cost-effective ways to create extra living space without extending your home. Whether you need a home office, gym, additional bedroom or family room, JR General Building delivers complete garage conversions — from structural alterations through to the final finish.

Call 07450 015 853
Free survey & quote
Fully managed project
Building Control handled
  • Credential 01

    SMAS Worksafe

    SMAS Worksafe accredited

  • Credential 02

    Marshalls Approved

    Marshalls Approved Installer

  • Credential 03

    City & Guilds

    City & Guilds qualified bricklayers

  • Credential 04

    CSCS Registered

    CSCS registered crews

Garage conversions across Milton Keynes & the Home Counties

A garage conversion is one of the most cost-effective ways to add a proper room to your home — without the expense and disruption of a full extension. Most conversions reuse the existing walls, roof and foundations, so you gain warm, usable living space quickly and affordably.

JR General Building designs and builds complete garage conversions across Milton Keynes and the surrounding Home Counties, managing every trade in-house from the first survey to the final coat of paint — including Building Control.

Unlock the space

Make your garage work harder

Many garages become little more than storage space. A professionally designed conversion unlocks the potential of your property while adding genuine, usable square footage to your home.

Our experienced team manages every stage of the project, so the new room feels like it has always been part of the house.

Popular garage conversion ideas

  • Home offices
  • Additional bedrooms
  • Children's playrooms
  • Home gyms
  • Utility rooms
  • Self-contained annexes

Every type

Integral, attached or detached — we convert them all

Whether it's an integral garage off the hallway, an attached single or double garage, or a detached garage to the side of the house, the right approach is different every time. We survey the structure, floor level and damp-proofing first, then build accordingly.

Garages we convert

  • Integral (built-in) garages
  • Attached single & double garages
  • Detached garages
  • Part-garage conversions (keep some storage)
  • Garage-to-annexe conversions

Complete service

A complete garage conversion service

Unlike many contractors, we complete the majority of the work using our own experienced trades. From first survey to final handover, every stage is carefully managed and kept tidy.

Our service includes

  • Structural alterations
  • Brickwork & blockwork
  • Foundations where required
  • Insulation & damp-proofing
  • Windows and doors
  • Electrical installation
  • Plumbing
  • Plastering
  • Flooring
  • Decoration-ready finish
  • Building Control coordination

Handled for you

Planning permission and building regs — sorted

Most garage conversions fall under permitted development and don't need planning permission, though there are exceptions — flats, listed buildings, conservation areas and homes under an Article 4 direction. Either way, a conversion must meet Building Regulations for insulation, damp-proofing, fire safety, ventilation and any structural work.

We check the planning position for your property up front and coordinate Building Control approval as part of the job, so nothing is left for you to chase.

Extra space. More value.

Design, build and transform — all under one roof, with our own trades on every project.

Compare

Garage conversion or extension?

We build both, so here's an honest comparison to help you weigh up the options.

Garage conversion
Extension
Typical cost
Lower — reuses existing walls, roof and foundations
Higher — built new from the foundations up
Disruption
Minimal — mostly internal work
Significant — groundwork and structure
Time on site
Around 3–5 weeks
Several months
Planning
Usually permitted development
Often needs planning permission
Space gained
One good-sized room
Larger, sometimes multi-room space
Best when
You want a room quickly and affordably
You need major extra space and can keep the garage

Not sure which suits your home? We'll give you honest advice on both at the free survey.

Cost & quotes

What affects the cost of a garage conversion

Every garage is different, so we quote each project individually after a free survey. The main things that move the price are:

We don't give vague ballpark figures over the phone. You get a clear, itemised written quote after we've seen the space — with no obligation.

Get your free quote

What affects the price

  • Single vs double garage (floor area)
  • Whether the floor, walls or roof need upgrading
  • Damp-proofing and insulation to current standards
  • Removing or bricking up the garage door
  • Adding plumbing for a kitchen, utility or bathroom
  • Extending heating and electrics into the new room
  • The level of finish and joinery you choose

Our process

How your garage conversion happens

One team, one point of contact, from the first visit to handover.

  1. 01

    Free survey & ideas

    We visit, measure up, check levels, damp and services, and talk through how you want to use the room.

  2. 02

    Quote & Building Control

    You get a clear written quote. Once you're happy, we handle Building Control and any approvals.

  3. 03

    The build

    Our own trades carry out the structural work, insulation, electrics, plastering and finishes — kept tidy throughout.

  4. 04

    Finish & handover

    We snag, clean up and hand over a warm, decoration-ready room that feels part of the house.

The JR difference

Why choose JR General Building?

  • Three generations of construction experience
  • In-house groundworkers, bricklayers and plasterers
  • SMAS Worksafe accredited
  • Building Control coordinated for you
  • Clear written quotations
  • High-quality, guaranteed workmanship

FAQs

Garage conversion questions, answered

The things homeowners most often ask us before starting a garage conversion.

Do I need planning permission for a garage conversion?

Most garage conversions are covered by permitted development and don't need planning permission. Exceptions include flats and maisonettes, listed buildings, conservation areas and homes affected by an Article 4 direction. We check your property's planning position before any work starts.

Do garage conversions need Building Regulations approval?

Yes. A conversion must meet Building Regulations for insulation, damp-proofing, fire safety, ventilation, electrics and any structural changes. We coordinate Building Control sign-off as part of the project.

How long does a garage conversion take?

Most single-garage conversions take around three to five weeks on site, depending on the amount of structural work, plumbing and the level of finish. We give you a programme with your quote.

Will a garage conversion add value to my home?

Converting a garage into good-quality living space usually adds value and makes a home more sellable, especially where the garage was only used for storage. We'll give you honest advice on parking and layout so the conversion works for buyers too.

Can I convert my garage into a bedroom, office or annexe?

Yes. Popular uses include home offices, bedrooms, gyms, playrooms, utility rooms and self-contained annexes. Rooms with sleeping or bathroom facilities have extra Building Regulations requirements, which we take care of.

Can you keep the look of the garage door?

Yes. We can brick up the opening to match the house or fit a dummy door so the front elevation still looks right — whichever suits the property.

Do you convert integral and detached garages?

We convert integral, attached and detached garages, as well as part-garage conversions where you want to keep some storage.

Will the new room be warm and dry?

Yes. We insulate the walls, floor and roof to current standards, install damp-proofing where needed and extend your heating, so the room is comfortable all year round.

Will I lose my parking?

You'll lose the garage as a parking space, but most homes keep driveway parking. We'll talk this through so you're happy with the trade-off before you commit.

Is a garage conversion better than an extension?

For adding a single room, a garage conversion is usually faster, cheaper and less disruptive than an extension, because it reuses the existing walls, roof and foundations. An extension makes more sense when you need significantly more space or want to keep the garage — we're happy to advise on both.

Should I get a Lawful Development Certificate?

Even where a conversion is permitted development, a Lawful Development Certificate from your council is useful proof that the work is lawful — which helps when you come to sell. We can advise whether one is worth obtaining for your property.

Can the new room be soundproofed?

Yes. Where the room adjoins living space or will be used as an office, gym or media room, we can add acoustic insulation to the walls, floor and ceiling to keep noise transfer to a minimum.

Do you handle the whole project?

Yes. From survey and Building Control to structural work, electrics, plastering and a decoration-ready finish — it is all done by our own team.

Ready to discuss your garage conversion?

Whether you're creating extra family space or increasing the value of your property, we'd be happy to discuss your ideas. Book your free site survey today.

Where we work

Based in Milton Keynes. Covering Milton Keynes and the Home Counties.

From the MK borough — Bletchley, Stony Stratford, Wolverton, Newport Pagnell — out to Bedford, Northampton, Aylesbury, Luton, Watford and Greater London. If you're unsure whether you're in our area, please call — we usually are.

Primary towns

  • Buckinghamshire
  • Bedfordshire
  • Northamptonshire
  • Hertfordshire
  • Greater London

Surrounding towns

  • Stony Stratford
  • Wolverton
  • Bletchley
  • Newport Pagnell
  • Cranfield
  • Olney
  • Towcester
  • Buckingham
  • Leighton Buzzard
  • Northampton
  • Bedford
  • Aylesbury
  • Luton
  • Hemel Hempstead
  • Watford
  • London

Map centred on Milton Keynes — coverage radiates across Buckinghamshire, Bedfordshire, Northamptonshire, Hertfordshire and into Greater London.