Garage conversions
Structural Calculations for Garage Conversions
Your price before you pay · Building control ready · Worked remotely · You choose the date
Converting your garage into a habitable room is one of the most cost-effective ways to add space and value to your home. Whether it becomes a bedroom, office, or living room, Calcs-Online provides the structural calculations you need to pass building control and get your project built safely — the floor slab, the walls, the roof, and every new opening, all assessed by our structural engineers.
- 9,000+ Projects Since 2012
- 100% Approval Rate on Our Calculations
- Structural engineers
- A clear price, and a date you choose
Every part of the structure, assessed — walls, floor, roof, and openings
Your garage conversion calculations
Every garage is different. Your calculations should be too.
Calculations for your garage
Integral or detached, concrete block, single brick or timber frame: the calculations are worked out for your garage type, wall construction and roof structure.
The whole structure, assessed
We assess floor slab condition, wall adequacy, roof loading, and the beam or lintel requirements for every new opening in your conversion.
Approved, or refunded
100% building regulations approval rate on 9,000+ projects since 2012, and a free refund if your calculations are ever not approved. The pack is prepared for what building control asks to see.
100% Building Regulations Approval Rate For Our Structural Calculations
What every quote includes
- Want an engineer to look first? Get in touch.
- Up to £500,000 insurance
- Money back if our calculations are not approved
- You choose the date; each date shows its price
- Worked by structural engineers
- A clear price, and a date you choose
What do garage conversion structural calculations include?
Turning a garage into a habitable room touches every part of the structure — not just the door opening. Your calculation package covers the whole conversion:
- Floor slab assessment — is the existing slab adequate, or does it need upgrading?
- Wall structural adequacy — cavity walls, single brick, or blockwork, each assessed correctly
- Roof load calculations — ensuring the existing roof structure can carry any new loads
- Beam and lintel design for all new openings — windows, doors, and internal openings
- Full building control compliance pack
- Contractor pack with a detailed specification for whoever builds it
How our pricing works
The quote sets out what is included, before you commit.
Get your price before you commit
You choose the date your calculations arrive, and each date shows its own price.
Just replacing the garage door?
If you’re only swapping the garage door for a window, standard door, or wall — and keeping the rest of the garage as it is — that’s a simpler job you can order online. It has its own page.
Garage door conversion structural calculations →Why choose Calcs-Online for garage conversion structural calculations?
Worked out for your garage
Every garage is different — concrete block, single brick, timber frame, integral or detached. We assess what you have and calculate what you need.
Building control ready
Our calculations are prepared specifically to meet building regulations. 100% approval rate on 9,000+ projects since 2012, or a free refund.
Worked remotely
We work from drawings, photos, and your project details, anywhere in the UK.
Your price first
Your quote tells you what you will pay before you commit.
A date that suits you
You choose the date your calculations arrive; each date shows its own price.
Talk to an engineer first
Want an engineer to look at your project before you order? Get in touch.
Common garage conversion challenges — and how we solve them
Is my garage slab adequate for a habitable floor?
A common question building control will ask. We assess the existing slab against the loads of a habitable room and specify any upgrades needed — so there are no surprises once the floor build-up goes in.
Are my garage walls structural enough?
Cavity walls, single brick and blockwork all behave differently. We calculate the adequacy of what is there and specify strengthening only where it is needed.
What happens to the garage door opening?
We design the lintel or beam for the new opening and specify the wall construction above it, whether you’re adding a window, a standard door, or bricking it up entirely.
Do I need planning permission?
Permitted development rights often cover garage conversions, but building regulations approval is always required. Our calculations are prepared specifically to satisfy building control.
Can I add a bathroom or bedroom in my garage?
Yes — with some additional structural considerations. We cover floor loading, drainage penetrations through the slab, and any roof modifications needed for ventilation or rooflights.
How it works
Get a quote
Complete our online quote form with your garage type, planned conversion scope, and any drawings or photos you have.
Project review
You get your price, then you choose the date that suits you.
Structural assessment
Our engineers assess the existing structure — walls, floor, roof, and any proposed openings — against the relevant building regulations.
Calculations and drawings
We produce your full structural calculation package, including any beam or lintel designs, load path analysis and a contractor pack to build from.
Delivery and support
Your calculations are delivered on the date you chose, ready for building control submission. Questions about them from building control or the builder come to us.
Get the structure right before work starts
Structural mistakes are expensive: work ripped out, repairs nobody budgeted for, an application refused.
Calculations checked before the build starts take those risks out. Building control sees what it needs, and whoever builds it knows exactly what to fit.
Calcs-Online works from your drawings and photos. Want an engineer to look first? Get in touch.
Talk to an engineer first
If you would like an engineer to look at your drawings and photos before you order, get in touch.
Worked from your drawings
Calcs-Online works from the plans and photos you send, and the calculations come back ready for building control.
Approved,
or refunded
Our structural calculations have a 100% approval rate across 9,000+ projects since 2012, and a free refund if yours are not approved.
“They asked good and very detailed questions of us and were very patient in dealing with our queries Lack of use of any jargon made things very understandable for us.”
FAQ
Questions
Do I need structural calculations for a garage conversion?
Yes — building regulations require structural calculations for any garage conversion to a habitable room. Your local authority will not issue a completion certificate without them.
How much do garage conversion structural calculations cost?
It depends on the scope of structural work required. You see your price before you pay.
What’s the difference between a garage conversion and a garage door conversion?
A full garage conversion transforms the entire garage into a habitable room — floor, walls, roof, and all openings are assessed. A garage door conversion only replaces the door opening with a window, standard door, or wall, and is a simpler service you can order online — see the garage door conversion page.
Do you need to visit my property?
No. Calcs-Online works from drawings, photos and your project details, anywhere in the UK. Our calculations have a 100% building regulations approval rate on 9,000+ projects since 2012, with a free refund if yours are ever not approved.
Will my calculations pass building control?
Yes: a 100% approval rate on 9,000+ projects since 2012. If yours were refused, you would get a refund.
Start your garage conversion project today
Get your price for your garage conversion — building control ready, worked remotely.
