Part single, part two-storey extensions in Denbigh
Adding a part single, part two-storey extension in Denbigh gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in Wales.
Useful details for planning a part single, part two-storey extension in Denbigh.
- Postcode districts
- LL16 and LL17
- County / area
- Clwyd, Wales
- Price region
- Wales
- Guide price
- £66,000–£91,000 (£1,840–£2,530 per m²)
- Approval route
- It may be permitted development if the ground floor goes no more than 4 m and the first floor no more than 3 m beyond the original rear wall, with the first floor 10.5 m from the rear boundary.
- Nearest towns
- Ruthin (6.3 miles), Abergele (9.8 miles), Rhyl (9.9 miles)
- Distance to Wrexham
- about 20 miles
- First visit
- Free, no obligation
About a part single, part two-storey extension
A part single, part two-storey extension suits you if you want a generous ground floor but only need one extra room upstairs, or if a full two-storey design would affect a neighbour too much. You get design options that test where the two-storey part works best, the approvals your nation needs, structural design, building regulations approval and the build, carried out by vetted teams working under S&K.
Denbigh sits about 20.0 miles from Wrexham. Closer to home, Ruthin is 6.3 miles away and Abergele 9.8 miles.
What it costs in Denbigh
Our guide for Wales is £1,840–£2,530 per m² including VAT. On a project with a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total), that puts a part single, part two-storey extension in Denbigh at roughly £66,000–£91,000. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.
| Spec | Per m² | A 6 m × 4 m ground floor and a first floor over half of it (36 m² in total) |
|---|---|---|
| Essential | £1,690–£2,330 per m² | £61,000–£84,000 |
| Standard | £1,840–£2,530 per m² | £66,000–£91,000 |
| Premium | £2,210–£3,040 per m² | £79,500–£109,500 |
Planning and building regulations in Denbigh
In Wales, a part two-storey rear extension can be permitted development if the first floor goes no more than 3 m and the ground floor no more than 4 m beyond the original rear wall, with the first floor at least 10.5 m from the rear boundary. Conservation areas and other protected areas are excluded. If the design falls outside these limits, a householder application costs £585.
Approval in Wales: Householder planning application: £585. Councils normally decide householder applications within 8 weeks.
Building regulations: Building regulations approval under the Welsh Approved Documents, which differ from England's in places (notably energy efficiency).
Design points for Denbigh homes
Structure at the step
The first-floor wall above often sits over the new open-plan space, so it needs a steel beam or frame to carry it. Loads come down at different points than in a full two-storey design, and the engineer sizes the foundations to suit each part.
The roof junction
Where the single-storey roof meets the two-storey wall you need a sound weathering detail, usually a lead or similar flashing, and enough height for roof lights or a lantern. We set the roof falls and the upstairs window sill heights together so they do not clash.
How we'd run your project
Start at your house
We come to your home in Denbigh, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Design and approvals
We draw the extension and check it against the rules for Wales, then apply for planning permission or a certificate of lawfulness, whichever fits.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.
Questions about part single, part two-storey extensions in Denbigh
How long does a part single, part two-storey extension take?
Allow 4 to 8 weeks for survey and design, then the approval period (councils normally decide householder applications within 8 weeks), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.
Which postcodes do you cover around Denbigh?
We cover Denbigh (LL16 and LL17) and nearby places including Ruthin, Abergele and Rhyl, plus the rest of Clwyd. The first site visit is free.
How much does a part single, part two-storey extension cost in Denbigh?
Our guide for Wales, which covers Denbigh, is £1,840–£2,530 per m² including VAT. A typical project with a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total) comes to about £66,000–£91,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
Which side should the two-storey part go on?
Usually the side furthest from the nearest neighbour's windows, so the single-storey part sits nearest them and keeps their light. Other factors are where the stairs land upstairs, which room needs the extra space and where drains run. We sketch options at the design stage and explain which is most likely to be approved.
Can the single-storey part be deeper than the two-storey part?
With planning permission, yes, and that is often the point of the design: the ground floor projects further into the garden while the first floor stays back from neighbours. Under permitted development, the depth limits for extensions of more than one storey can apply to the whole extension, so we confirm which route applies before drawings are finalised.
Nearby
Nearby towns we cover for part single, part two-storey extensions:
Other extensions in Denbigh
- Rear
- Side
- Wraparound
- Over a garage
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Denbigh · Part single, part two-storey extensions across Clwyd
The quickest next step is a visit. We'll look at your house in Denbigh and give you an honest view of the options.