Menai Bridge · Gwynedd and Anglesey

Extra bedroom and en-suite extensions in Menai Bridge

Want to stay in Menai Bridge but need more space? An extra bedroom and en-suite extension adds floor area on two levels without giving up much garden. Here's what's involved.

Useful details for planning an extra bedroom and en-suite extension in Menai Bridge.

Postcode districts
LL56 and LL59
County / area
Gwynedd and Anglesey, Wales
Price region
Wales
Guide price
£51,500–£69,500 (£1,840–£2,480 per m²), plus £5,500–£11,000 for the en-suite
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
Bangor (Gwynedd and Anglesey) (1.7 miles), Bethesda (5.6 miles), Llangefni (6.2 miles)
Distance to Bangor (Gwynedd and Anglesey)
about 1.7 miles
First visit
Free, no obligation

About an extra bedroom and en-suite extension

An extra bedroom and en-suite extension is a two-storey extension planned around a new double bedroom with its own shower room on the first floor, with a ground-floor room below. It is one of the most effective ways to add space for a growing family. Nationwide's 2025 research linked adding a double bedroom and bathroom to a three-bed, one-bathroom house with value gains of up to 24%.

We cover postcode districts LL56 and LL59 in and around Menai Bridge, along with neighbouring Bangor (Gwynedd and Anglesey), Bethesda and Llangefni.

What it costs in Menai Bridge

Our guide for Wales is £1,840–£2,480 per m² including VAT. On a project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space), that puts an extra bedroom and en-suite extension in Menai Bridge at roughly £51,500–£69,500 (plus £5,500–£11,000 for the en-suite). Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£1,690–£2,290 per m²£47,500–£64,000
Standard£1,840–£2,480 per m²£51,500–£69,500
Premium£2,210–£2,980 per m²£62,000–£83,500

Planning and building regulations in Menai Bridge

In Wales, an extra bedroom at the rear can be permitted development if the first floor goes no more than 3 m beyond the original rear wall and stays 10.5 m from the rear boundary. A two-storey side extension can also qualify if it is 10.5 m from the side boundary, set back 1 m and adds no more than 50% width. Otherwise the fee is £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 Menai Bridge homes

Sound and privacy

Bedrooms above a kitchen or family room benefit from an insulated floor to reduce noise. Side-facing upstairs windows usually have to be obscure-glazed, so we place the main bedroom window to the rear and the en-suite window to the side where possible.

Planning the en-suite

An en-suite needs a route for the soil pipe to the drains, enough fall for waste water and an extract fan to the outside under Part F. Placing it over the ground-floor utility or near an existing drain keeps pipework short and hidden.

How we'd run your project

  1. Visit and first ideas

    One of our team visits your house in Menai Bridge, checks the walls, roof and drains, and sketches out options with you.

  2. Get it approved

    Once you're happy with the design we submit it to the council for Menai Bridge and deal with any questions from the planning officer.

  3. Detail and price

    Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.

  4. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about extra bedroom and en-suite extensions in Menai Bridge

How much does an extra bedroom and en-suite extension cost in Menai Bridge?

Our guide for Wales, which covers Menai Bridge, is £1,840–£2,480 per m² including VAT. A typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £51,500–£69,500 (plus £5,500–£11,000 for the en-suite). Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Which postcodes do you cover around Menai Bridge?

We cover Menai Bridge (LL56 and LL59) and nearby places including Bangor (Gwynedd and Anglesey), Bethesda and Llangefni, plus the rest of Gwynedd and Anglesey. The first site visit is free.

Who handles building regulations for a project in Menai Bridge?

We handle it as part of the project. What's needed in Wales: building regulations approval under the Welsh Approved Documents, which differ from England's in places (notably energy efficiency). We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

Can an en-suite go in a room with no window?

Yes. A shower room without a window is allowed, provided it has a mechanical extract fan to the outside that meets Part F. Many people prefer a window for daylight, but if it faces a neighbour it will usually need obscure glass. We plan the extract route early so the duct is hidden.

What goes on the ground floor below a new bedroom?

Whatever suits you: a bigger kitchen, a family room, a study, a utility or a downstairs shower room. The ground floor usually costs about the same whatever it is used for, apart from kitchen units and bathroom fittings, which are priced separately.

Nearby

The same service in neighbouring towns:

Other extensions in Menai Bridge

All two-storey extension services in Menai Bridge · Extra bedroom and en-suite extensions across Gwynedd and Anglesey

The quickest next step is a visit. We'll look at your house in Menai Bridge and give you an honest view of the options.

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