Garage Conversion Cost Guide for Brighton & Hove Homes
Realistic budgets, hidden extras and money-saving tips for coastal properties.
Why Garage Conversion Costs Vary So Widely
Brighton & Hove garages range from 1930s brick boxes to Victorian coach houses made of bungaroosh. Key drivers that push budgets up or down include:
Structural upgrades – steel goal-posts, underpinning shallow footings, hot-lime pinning for bungaroosh
Services – plumbing for en-suites, new consumer unit, data cabling, MVHR ventilation
Finishes – engineered oak and bespoke joinery versus sheet vinyl and off-the-shelf cabinets
Compliance fees – Building Control, structural engineer, SAP assessor, air-pressure test
Planning – full application and heritage reports if the façade faces a conservation street
Typical Spend Bands (Spring 2025)
Lean home office spec
Basic single garage, no bathroom, entry-level electrics
Expect £28 000 – £34 000 plus VAT
Mid-spec guest room with WC
New soil pipe or macerator, better insulation, two rooflights
Budget £38 000 – £45 000 plus VAT
High-spec annexe or gym
Double garage, en-suite shower, UFH, bespoke storage, acoustic floor
Range £55 000 – £70 000 plus VAT
Prices assume standard brick construction; bungaroosh remediation adds roughly 10–15 percent.
Cost Breakdown – Where the Money Goes
Design and approvals
Measured survey and concept drawings
Planning or lawful-development fee
Structural calculations
Structural and shell
Garage-door removal and goal-post frame
New cavity-wall infill or glazed screen
Floor slab insulation and screed
Envelope upgrades
Wall insulation, battening and lime or gypsum plaster
Roof insulation under deck or rafters
External lime render or brick-slip cladding (if required)
First-fix services
New ring main on RCBOs
Plumbing runs for radiators or UFH manifold
MVHR or humidity-sensing extract ducting
Second-fix and finishes
Flooring, skirting, architraves
Socket plates, switchgear, light fittings
Decoration and snagging
Professional and statutory
Building Control plan check and inspections
SAP calc and U-value report
Air-pressure test (optional but future-proofs EPC)
Hidden Extras Brighton Homeowners Encounter
Replacing corroded steel lintels in sea-air zones
Upgrading fuse board if spare capacity is lacking
Lime-render patches where bungaroosh walls crumble under old cement
Cycle storage or transport statements requested by planners
Unforeseen drainage reroutes when sewers run beneath the slab
Keep a 10–15 percent contingency for surprises—especially on period property conversions.
Value Boost and Payback
A heated, fully insulated office or bedroom in Brighton can add £40 000–£60 000 to market value, often covering the build cost.
EPC uplift by one band reduces energy bills, improving lender and buyer appeal.
Self-contained annexes generate £70 – £120 per night on Airbnb once council licensing is in place.
Financing Options
Further-advance mortgage at 4–5 percent APR over the existing term
Home-improvement loan from local credit union (typical 6.9 percent APR)
Green-energy grants where external-wall insulation is included
0 percent VAT on certain energy-saving measures until 2027
Cost-Saving Tips That Don’t Compromise Quality
Retain part of the original slab if depth and damp levels allow—saves screed pour.
Choose factory-finished roof lights; onsite frame painting adds labour.
Run heating off existing boiler circuit instead of installing a standalone electric system.
Opt for mineral-wool insulation in timber studs: cheaper than PIR and breathable for bungaroosh.
Stage the project: shell out and first fix in phase one, finishes later when budget allows.
Suggested Next Reads
USE THE FORM BELOW TO GET YOUR FREE QUOTE TODAY!
Safe-Bricks Limited © 2025. All rights reserved.