Two-storey wraparound extensions in Caernarfon

The basics for Caernarfon at a glance.

Postcode districts: LL54, LL55 and LL61
County / area: Gwynedd and Anglesey, Wales
Price region: Wales
Guide price: £111,000–£152,000 (£1,980–£2,710 per m²)
Approval route: Usually needs planning permission, because the combined side and rear works rarely meet every permitted development test.
Nearest towns: Menai Bridge (7.3 miles), Llangefni (8.1 miles), Bangor (Gwynedd and Anglesey) (8.3 miles)
Distance to Bangor (Gwynedd and Anglesey): about 8.3 miles
First visit: Free, no obligation

About a two-storey wraparound extension

A two-storey wraparound extension suits a house with space both beside it and behind it, where you want to transform the layout rather than add a single room. You get one design for the whole L-shape, the planning application, structural design for the corner and the openings into the house, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.

Caernarfon sits about 8.3 miles from Bangor (Gwynedd and Anglesey). Closer to home, Menai Bridge is 7.3 miles away and Llangefni 8.1 miles.

What it costs in Caernarfon

Expect a two-storey wraparound extension in Caernarfon to land somewhere around £111,000–£152,000 for an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). Our Wales guide rate is £1,980–£2,710 per m², including VAT. Professional fees for drawings and the structural engineer are listed separately on our prices page.

Spec	Per m²	An L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space)
Essential	£1,820–£2,500 per m²	£102,000–£140,000
Standard	£1,980–£2,710 per m²	£111,000–£152,000
Premium	£2,370–£3,260 per m²	£133,000–£182,500

Planning and building regulations in Caernarfon

In Wales, a wraparound would have to pass both the side and rear tests to be permitted development: 10.5 m to the opposite side boundary, a 1 m set-back from the front and no more than 50% added width, plus the 4 m and 3 m rear depth limits and 10.5 m to the rear boundary. Many wraparounds therefore need a householder application, which 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 Caernarfon homes

Daylight to the middle

A deep L-shaped plan can leave the middle of the ground floor dark, because the old rear rooms are now enclosed. We use wide rear openings, a well-placed stair and, where part of the extension is single storey, roof lights, while keeping total glazing within the Part L allowance.

Two roofs that meet

A wraparound needs the side roof and rear roof to join cleanly, often with a valley or hip where they meet. Getting pitches and ridge heights right keeps rainwater moving and avoids a bulky mass at the back corner, which neighbours and planners notice.

How we'd run your project

Visit and first ideas
One of our team visits your house in Caernarfon, checks the walls, roof and drains, and sketches out options with you.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Caernarfon.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about two-storey wraparound extensions in Caernarfon

How long does a two-storey wraparound 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 Caernarfon?

We cover Caernarfon (LL54, LL55 and LL61) and nearby places including Menai Bridge, Llangefni and Bangor (Gwynedd and Anglesey), plus the rest of Gwynedd and Anglesey. The first site visit is free.

Do I need planning permission for a two-storey wraparound extension in Caernarfon?

Caernarfon is in Wales, so Wales planning rules apply. Usually needs planning permission, because the combined side and rear works rarely meet every permitted development test. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Can I stay at home during a wraparound extension?

Many people do, but a wraparound affects two sides of the house and usually the kitchen, so there will be weeks without a full kitchen. We plan a temporary kitchen, keep a route through the house and seal off the work area. For some families, moving out while the rear wall is opened up is easier.

Can a wraparound extension be part single, part two-storey?

Yes. Many wraparounds keep the rear part single storey with roof lights over the kitchen and put the two-storey part to the side. This can reduce the effect on neighbours and the cost. We set out both options at the design stage, so you can compare floor space against price before choosing.

Nearby

Other towns near Caernarfon:

Other extensions in Caernarfon

All two-storey extension services in Caernarfon · Two-storey wraparound extensions across Gwynedd and Anglesey

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