A bricklayer laying facing bricks on a new cavity wall, string line and spirit level in place

garage · provisional

Attached garage: how it is priced

Attached to the house, a garage shares a wall and often a roof line. Fewer bricks than detached, but the junction with the house, the fire separation and the matching finish all cost something.

FICTIONAL WORKED EXAMPLE · 6m × 3.5m (external) · 17.3 m² internal · finish: complete

£39,218.40

inc. VAT at 20% · £32,682.00 before VAT · about £1,891.32/m² · roughly 3 weeks on site

Materials (49 lines, catalogue allowances dated 2026-09-24)£11,346.80Labour (370 person-hours at a blended £30/hr)£11,084.85Provisional allowances (3)£1,735.00Plant£545.00Overheads 10% + contingency 5%£3,706.75Profit (15% markup)£4,262.76

WHERE THE MONEY GOES (AT COST)

Roof£6,550.75External walls£5,458.25Windows & external doors£2,430.00Floors£2,232.40Excavation & foundations£2,098.25Waste removal£1,460.00Drainage£1,130.00Fees & approvals£900.00

Open the full line-by-line example →

Default answers, a blended £30/hr labour rate and dated catalogue allowances. Your job, your rates and your merchant prices will differ — that is the point of the tool. Templates marked provisional are being validated against measured projects; every estimate says so.

What the wizard asks

Attached or detached — Is the garage attached to the house?
Dimensions — Are these internal or external measurements?, Length — length, Width — width (m) — 3–3.5m single, 5.5–6m double, Wall height to eaves
Roof — Roof type, Pitch, Covering, Rooflights
Walls — Wall construction, Outside finish
Ground and foundations — Foundation type, Foundation depth, Ground, Floor construction…
Windows and doors — Openings
Site — Anything to take down first?, Drainage, Access for deliveries and plant
Electrics — Sockets and switches, Light fittings
Inclusions, exclusions and notes — Exclusions, Notes for the estimate

Assumptions this example carries

Garage floor: 150mm concrete slab, power-floated, uninsulated.
Foundations: trench fill 600mm wide × 1.0m deep in GEN1 concrete under all new external walls.
Ground floor: 150mm concrete slab on 150mm compacted hardcore.
External walls: facing brick outer skin, 100mm full-fill insulated cavity, 100mm block inner skin.
Gable roof at 30° on manufacturer-designed trusses, covered in concrete interlocking tile. Truss price is an allowance until the manufacturer quotes.
Rainwater to a new soakaway at least 5m from the building; a percolation test may be required by building control.
The existing consumer unit has spare capacity for the new circuits; if not, a new unit is extra.

Priced work packages

Preliminaries & site setup · Demolition & clearance · Excavation & foundations · Floors · External walls · Roof · Windows & external doors · Drainage · Electrical · Scaffold & access · Plant hire · Waste removal · Deliveries · Testing & certification · Fees & approvals