This quotation sets out the work, the price and what is provisional. Please read the assumptions and exclusions before accepting.

What we will build

• Garden room / home office: 4m × 3m (external), approximately 8.2 m² internal floor area.
• Walls: insulated timber frame finished in composite cladding.
• Roof: flat warm-deck roof in epdm.
• Foundations and floor: trench-fill foundations, concrete slab with insulation.
• Windows and doors: 1 × bifold 2.4×2.1m, 1 × window 0.9×0.9m.
• Completed to: complete finish (standard specification).
• Services: 6 power points, 4 light fittings, electric panel heaters.

Price breakdown

Assumptions this price relies on

• Under 2.5m high at the eaves and within permitted development limits; building regulations apply if over 30 m² or with sleeping accommodation.
• Foundations: trench fill 600mm wide × 0.6m deep in GEN1 concrete under all new external walls.
• Ground floor: 100mm concrete slab on 150mm compacted hardcore with 100mm PIR insulation.
• External walls: manufacturer-designed timber frame with insulated studs, breather membrane and a masonry or clad outer skin. The frame price is an allowance until the manufacturer quotes.
• Flat roof: warm-deck construction with 120mm PIR, 47×195 C24 joists at 400 centres with firrings to fall, epdm rubber roof membrane with adhesives & trims.
• 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.
• No planning application fee, party wall surveyor or planning drawings are included. Permitted development or existing consent is assumed.
• Work to comply with the building regulations applying in England; design by others where a design is required.

Not included

• Planning application, drawings and party wall matters
• Furniture, appliances and loose fittings
• Landscaping and reinstatement beyond the working area
• Anything found on opening up that could not be seen at survey
• Decking and paths

Programme, validity and payment

• Estimated time on site: about 4 weeks, subject to weather, materials and approvals.
• Payment in stages:

  Deposit on acceptance	10%	£4,596.48
  Watertight shell	40%	£18,385.92
  First and second fix complete	30%	£13,789.44
  Completion and handover	20%	£9,192.96

• Payment: Each stage is invoiced when it is reached and is due within 7 days.