Home office extensions in Penarth
From the first sketch to final sign-off, we plan and build home office extensions in Penarth and the surrounding South Glamorgan area.
- Guide price in PenarthFrom £14,500 inc VAT
- PlanningWelsh permitted development rules (rear up to 4 m)
- Build time8–12 weeks on site
- Postcode districtsCF64
Covering Penarth
Site visits are available across Penarth (CF64). We also work in nearby Cardiff (3 miles), Barry (5 miles), Cowbridge (12 miles).
Caerphilly, in Mid Glamorgan, is roughly 10 miles from Penarth and also on our list. In Wales, terraced houses with rear offshoots are common in the towns, while detached houses and bungalows dominate in rural areas.
Who a home office extension suits
- Homes where a loft or garden room is not practical
- People who work from home most of the week
- Households that need a second quiet room
North-facing glass and rooflights give steadier light for screen work. Where the office faces south, we use deeper reveals or external shading to keep glare and heat down.
What should I budget for a home office extension in Penarth?
Labour and material costs vary across the UK, so for Penarth we use our Wales factor (×0.93). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Penarth: £1,720 to £3,160 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 3.2 m 8 m² | £14,500 – £18,000 | £15,500 – £20,500 | £20,000 – £25,500 |
| 3 m × 3.6 m 11 m² | £18,500 – £23,000 | £21,500 – £28,000 | £27,500 – £35,000 |
| 3 m × 5 m 15 m² | £25,500 – £31,000 | £29,500 – £38,000 | £37,500 – £47,500 |
Try the guide-price tool to see a range for your own size and finish.
Will the council need to approve it?
In Wales a single-storey rear extension can usually project up to 4 m beyond the rear wall without a planning application, if it is no more than 4 m high, keeps eaves to 3 m and overall height to 4 m within 2 m of a boundary, and covers no more than half the land around the original house. Wales has no larger home extension prior approval scheme.
In a conservation area, national park, National Landscape or World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building over or within 3 m of a public sewer needs the water company's consent before the foundations go in.
The Party Wall etc. Act 1996 applies in Wales as in England: notice must be served before work to a shared wall, building on the boundary, or excavating close to a neighbour's foundations.
Applications are decided by the local planning authority (your county or county borough council, or the national park authority).
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Home office extension questions answered
Do I need building regulations approval in Penarth?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who do I contract with for a home office extension in Penarth?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Penarth, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Can I claim the cost against tax?
Building work on your home is not normally an allowable business expense, and claiming it can have capital gains tax effects. Speak to an accountant before assuming any tax relief.
How much does a home office extension cost?
Our guide range is about £1,720 to £3,160 per m² including VAT. An 11 m² standard-spec office is typically £21,500 to £28,000 in Penarth.
Book a free site visit in Penarth
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.