Thinking about extending your home in Hackney or the surrounding E postcodes? Whether you’re planning a light-filled kitchen-diner in a Victorian terrace near London Fields, a double-storey addition in Stoke Newington, or a creative side return in Dalston, understanding realistic 2025 extension costs is key before you begin.
This guide is written for Hackney homeowners — from Clapton and Homerton to Hoxton and Shoreditch — who want clear cost insights, planning guidance and trusted local advice. It’s based on current London market averages and the on-site experience of Buildaway, a reliable East London construction company known for transparent quotes and an 18-month labour warranty.
How Much Does a House Extension Cost in Hackney (2025)?
Prices in Hackney reflect inner East London’s growing property demand — generally higher than outer London suburbs, but still competitive given the area’s strong housing stock and transport links. Expect these average figures:
Single-Storey Rear Extension
- Build-only: £2,200 – £2,800 per m²
- Fully finished with kitchen: £2,800 – £3,500 per m²
- Example: a 25 m² kitchen-diner = £55,000 – £70,000 build-only or £70,000 – £90,000 turnkey
Double-Storey Rear Extension
- Build-only: £2,000 – £2,600 per m²
- Fully finished: £2,600 – £3,300 per m²
- Example: 40 m² over two floors = £80,000 – £110,000 build-only or £105,000 – £130,000 turnkey
Side Return & Wrap-Around Extensions
Typically match single-storey rates: £2,200 – £2,900 per m² depending on structure and roof glazing. These are solid, realistic Hackney rates for insured, Building-Control-compliant contractors who deliver quality and aftercare.
What Drives the Price Up or Down
- Size & footprint – more square metres = more materials, labour, and finishes.
- Structural steel (RSJs) – removing load-bearing walls adds £2k–£6k+.
- Foundations & drainage – tricky ground or drainage diversions increase cost.
- Roof style & glazing – flat roofs with rooflights are cheaper; bifolds add £3k–£8k+.
- Kitchens & bathrooms – kitchens £10k–£25k+, bathrooms £6k–£15k+.
- Heating & plumbing – new bathrooms may need a Megaflo/unvented system (£2.5k–£4.5k).
- Finishes & joinery – bespoke carpentry and premium flooring add value.
- Access & parking – Hackney’s narrow streets and limited parking can slightly raise costs.
Planning Permission & Building Control in Hackney
- Many single-storey rear or side extensions qualify under Permitted Development (PD) if within set limits.
- Full planning is needed for double-storey, front, or larger rear extensions.
- Conservation Areas (common in Clapton, De Beauvoir Town, and Hackney Central) remove PD rights, so planning approval is required.
- Building Control sign-off is always mandatory for structure, insulation, drainage and electrical compliance.
A reputable contractor can work alongside your architect to prepare drawings, calculations, and planning submissions smoothly.
How Long Will It Take?
- Design & planning: 4–12 weeks
- Technical drawings & approvals: 2–6 weeks
- On-site build:
- Single-storey: 10–14 weeks
- Double-storey: 14–20 weeks
- Add extra time for bespoke glazing or custom kitchens.
Typical Full Project Budget Breakdown (30 m² Double-Storey)
| Element | Typical Cost |
|---|---|
| Core structure & shell | £70,000 – £85,000 |
| Windows / doors / glazing | £5,000 – £10,000 |
| Kitchen supply & fit | £12,000 – £25,000 |
| Bathroom fit-out | £6,000 – £12,000 |
| Heating / boiler / Megaflo | £3,000 – £5,000 |
| Flooring & decorating | £5,000 – £15,000 |
| Professional fees & permissions | £3,000 – £8,000 |
| Total realistic range: | £100,000 – £135,000 |
(Larger or more bespoke designs may exceed £150k.)
Why Hackney Clients Choose Buildaway
- East London expertise — familiar with Hackney terraces, planning rules and council expectations.
- Transparent quotes — detailed, staged pricing (no hidden costs).
- 18-month labour warranty — above standard industry coverage.
- Fully insured & compliant — Gas Safe, NICEIC, and all liability certificates.
- Reliable project management — managing logistics, neighbours, and Building Control coordination.
Frequently Asked Questions
Do I need planning permission for my Hackney extension?
Often not for smaller single-storey rears, but homes in conservation areas or double-storey builds will need it.
Can I live at home during construction?
Usually yes, especially for single-storey projects — though dust and noise are inevitable.
Will I need to upgrade my boiler or water system?
If adding extra bathrooms or a large kitchen, upgrading to a Megaflo or modern boiler is smart.
What guarantees do you provide?
Buildaway includes an 18-month labour warranty for all structural and finish work.
Next Steps for Hackney Homeowners
If you’re ready to explore your Hackney extension:
- Book a free home visit to assess space and budget.
- We can arrange design and planning packages if you don’t yet have drawings.
- Get a transparent, detailed quote outlining every cost clearly.
📞 020 8108 0388
📧 info@buildaway.co.uk
Buildaway — trusted by Hackney homeowners for quality extensions, renovations and kitchens done right.