Giffnock (G46) is one of East Renfrewshire’s most sought-after residential areas, with a mix of 1930s–1960s detached and semi-detached properties that offer excellent scope for rear extensions. Home Decor Zone Ltd builds house extensions across Giffnock, Orchard Park and Broom, with a track record of open-plan kitchen extensions and garden-facing family rooms.
What our prices include
All prices on this page are labour plus building materials — plaster, plasterboard, pipework and plumbing fittings, electrical cable and accessories, timber, adhesives, grout, sealants and fixings. Every quote is itemised line by line.
Not included (you buy these, or we can supply and add them to the quote): kitchen units and appliances, bathroom suites and tiles, flooring, paint and any bespoke joinery — quoted separately or supplied by you. You get our 10% trade discount at Topps Tiles, B&Q TradePoint, Wholesale Domestic and Victoria Plumbing.
Extension Options in Giffnock
Single-Storey Rear Extension — most common in G46
Giffnock’s post-war detached and semi-detached stock typically has generous rear gardens and traditional cavity wall construction — ideal for a straightforward rear extension. A 20–30m² extension creates a large open-plan kitchen-dining-living space with bifold doors to the garden. Most qualify as permitted development without planning permission from East Renfrewshire Council.
Open-Plan Kitchen Extension
Combining a rear extension with the removal of the existing kitchen/dining wall (steel beam installation) is the most transformative project we carry out in Giffnock — turning a 1960s cellular ground floor into a modern open-plan family space.
House Extension Cost in Giffnock 2025–26
| Type | Cost | Time |
|---|---|---|
| Single-storey rear (20m²) | £48,000–£72,000 | 12–16 wks |
| Single-storey rear (30m²) | £70,000–£108,000 | 14–18 wks |
| Two-storey | £90,000–£142,000 | 20–26 wks |
Planning & Building Warrant — East Renfrewshire Council
Giffnock is in East Renfrewshire. Single-storey rear extensions up to 4m (detached) or 3m (semi) typically qualify as permitted development. A building warrant from East Renfrewshire Building Standards is always required. We handle the full warrant application and obtain your completion certificate.
FAQ
Do I need planning permission for a house extension in Giffnock?
Most standard rear extensions up to 4m (detached) or 3m (semi) qualify as permitted development from East Renfrewshire Council. A building warrant is always required. We confirm what’s needed at your free survey.
How much does a house extension cost in Giffnock?
A 20m² single-storey rear extension in Giffnock costs approximately £48,000–£72,000 inc. building warrant. We provide a fixed-price written quote after a free survey.
Free Extension Survey in Giffnock
We visit your G46 property and provide a fixed-price written quote. No obligation.
Related services & areas
Other services in Giffnock: Loft Conversion Giffnock · Kitchen Renovation Giffnock · Bathroom Renovation Giffnock · Bathroom Fitters Giffnock
House Extensions in nearby areas: Clarkston · Bearsden · Newton Mearns
See all our house extensions across Glasgow.
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