Garage Conversion FAQs & Mistakes to Avoid – Brighton & Hove

Answers to the questions homeowners ask most, plus the slip-ups that cost time and money.

Fast Answers to Common Questions

Can I live in my converted garage all year?
Yes—if the walls, floor and roof meet Part L insulation targets and you install continuous ventilation, the space stays warm and condensation-free.

Will I need planning permission?
Most single garages in Brighton convert under Permitted Development, but conservation areas, listed buildings and façade changes require an application.

Do Building Regulations apply even without planning?
Absolutely. Your conversion must pass structure, insulation, fire safety and electrics inspections.

How long does a single-garage conversion take?
Four to six on-site weeks once permissions, engineer calcs and materials are ready.

Does a conversion affect council tax?
Brighton & Hove City Council rarely re-band for a single extra room, but check if you add a self-contained annexe.

Can I keep part of the garage for storage?
Yes—build a stud wall 600 mm behind a new insulated roller door to create a secure store while converting the rest.

Will a macerator toilet be noisy?
Modern units run at 45–55 dB. Fit acoustic matting and mount the pump on rubber feet to reduce sound.

Is electric under-floor heating expensive to run?
At off-peak rates it costs about 15–20 p per hour in a well-insulated 15 m² room; pair with a floor sensor thermostat for efficiency.

Biggest Mistakes Brighton Homeowners Make

Skipping a moisture survey in bungaroosh walls
Trapped damp emerges through new plaster—always test with capacitance and carbide meters first.

Using sand-cement render on lime-rich masonry
Cement locks in moisture and forces salts outward, leading to bulges within two winters.

Undersizing the goal-post frame
Garage door openings carry roof loads; cheap 102 × 102 UC beams often deflect. Follow engineer calcs and include padstones.

Ignoring airtightness
Gaps around beams and service penetrations create cold draughts and moisture pockets. Tape everything with vapour-control tape.

Forgetting incoming gas and water routes
Existing meter boxes sometimes block the new wall line. Relocating them mid-build is costly and delays inspections.

Installing bathroom extract that vents into the loft
Moist air rots rafters; duct fans through the roof with back-draught shutters and marine-grade terminals.

Leaving electrical upgrades until the end
Old fuse boards lack spare ways. Confirm capacity at quote stage to avoid emergency consumer-unit swaps.

Choosing glossy vinyl paint over lime plaster
Low-permeability paint traps moisture behind vibrant colours. Use mineral or clay paint on breathable substrates.

Underestimating furniture clearances
A guest sofa-bed needs 2 m when unfolded; plan circulation paths before walls go up.

Pro Tips to Dodge Every Pitfall

Order steel beams two weeks ahead—Brighton suppliers book slots fast.
Photograph each hidden layer for your Building Control file and future buyers.
Wrap goal-post legs in 10 mm aerogel to eliminate cold-bridge condensation.
Install a Wi-Fi humidity sensor; set alerts at 65 % RH to catch problems early.
Ask neighbours about parking before losing your off-street bay; sometimes a cycle store placates objections.
Allow a 10–15 % contingency—bungaroosh always hides one surprise.