4 garden room builders in Hampshire
From Portsmouth and Southampton to Basingstoke. These are the garden room firms we have checked so far, with the facts each one publishes on its own website.
Listed in alphabetical order – not ranked. Every fact comes from the firm's own website, checked 20 October 2026. We haven't used these firms ourselves, and none of them has paid to be here. Where a firm doesn't publish something, we say “not stated”.
Brackenwood
- Based in
- Basingstoke (head office and showroom, Kimbell Road, RG22 4AT)
- Area covered
- Hampshire, Berkshire, Surrey, Dorset, West Sussex, Wiltshire and Oxfordshire.
- Prices
- not stated
- Insulation
- Honeycomb foil insulation with A++ rated windows and doors; fully insulated for year-round use
- Planning help
- not stated
- Guarantee
- 10-year insurance-backed guarantee on every project
- Also says
- Family-owned home improvement firm established in 1987 (windows, doors and conservatories as well as garden rooms). Solid timber garden rooms, prefabricated; says it uses its own craftsmen, no subcontractors.
CS Garden Offices
- Based in
- Gosport (workshop at 104 Fareham Road, PO13 0BA)
- Area covered
- Hampshire and the South: Portsmouth, Fareham, Southampton, Chichester, Winchester, Andover, Petersfield and surrounding areas. Also has pages for Dorset, Surrey, Sussex and Wiltshire.
- Prices
- From £8,982 (smallest standard garden office size; VAT not stated)
- Insulation
- Structural insulated panels with a 75mm polyurethane core; quotes a U-value of 0.13
- Planning help
- Says most garden offices need no planning permission and it can guide you through the process where needed.
- Guarantee
- 10-year guarantee
- Also says
- Modular SIP buildings made in its Gosport factory; says design, manufacture, groundworks and installation are all in-house, with a typical install in one day.
Southwicks Garden Rooms
- Based in
- Stubbington, Fareham (Crofton Retail Centre, PO14 2PE)
- Area covered
- South Hampshire, including Locks Heath, Park Gate, Sarisbury Green, Bursledon, Hamble, Wickham, Bishop's Waltham, Titchfield, Gosport, Botley, Whiteley, Lee-on-the-Solent, Hedge End, Denmead and Netley.
- Prices
- not stated
- Insulation
- Insulation to floor, walls and roof (Celotex under the floor), for year-round use
- Planning help
- not stated
- Guarantee
- 10-year structural guarantee, also covering design and manufacturing faults (exterior must be repainted every two years); 20-year Firestone EPDM roof guarantee
- Also says
- Southwicks Garden Rooms Ltd, registered in Portsmouth. Double-glazed windows; buildings sit on tanalised bearers on concrete foundations.
The Cottage Workshop
- Based in
- Lower Upham, near Southampton (SO32 1HH)
- Area covered
- Site visits within 50 miles of Southampton; installs across the South of England.
- Prices
- not stated
- Insulation
- not stated
- Planning help
- not stated
- Guarantee
- not stated
- Also says
- Small family-run workshop hand-making bespoke timber garden offices, summerhouses and sheds; offers heating, electrics and built-in furniture.
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