Llanidloes · Powys

Two-storey side extensions in Llanidloes

For a two-storey side extension in Llanidloes, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for Powys.

Llanidloes: the key facts for this kind of project.

Postcode districts
SY17, SY18 and SY19
County / area
Powys, Wales
Price region
Wales
Guide price
£79,000–£106,500 (£1,890–£2,530 per m²)
Approval route
Can be permitted development in Wales if it is 10.5 m from the side boundary, set back 1 m from the front and doesn't widen the house by more than half; otherwise planning permission.
Nearest towns
Newtown (11.1 miles), Llandrindod Wells (15.9 miles), Builth Wells (21.5 miles)
Distance to Newtown
about 11.1 miles
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

We cover postcode districts SY17, SY18 and SY19 in and around Llanidloes, along with neighbouring Newtown, Llandrindod Wells and Builth Wells.

What it costs in Llanidloes

Most of the cost of a two-storey side extension is set by its size and specification. For Llanidloes and the rest of Wales, our guide is £1,890–£2,530 per m² including VAT, so about £79,000–£106,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Keep a contingency of around 10% for things nobody can see until the ground is opened up.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£1,740–£2,330 per m²£73,000–£98,000
Standard£1,890–£2,530 per m²£79,000–£106,500
Premium£2,260–£3,040 per m²£95,000–£127,500

Planning and building regulations in Llanidloes

In Wales, a two-storey side extension can be permitted development if it is at least 10.5 m from the boundary opposite the side wall, set back at least 1 m from the front of the house and does not increase the house's widest width by more than 50%. If it fails any test, or the house is in a protected area, 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 Llanidloes homes

Avoiding a terracing effect

Where semi-detached houses sit close together, side extensions on neighbouring houses can join up and turn a row of pairs into a terrace. Many councils ask for a gap to the boundary at first floor to stop this, so we check local guidance before fixing the width.

Side windows, boundaries and gutters

Upstairs windows in the side wall face the neighbour, so they are usually obscure-glazed and fixed, or left out. Building close to the boundary also raises questions about foundations, overhanging gutters and access for maintenance, so we design the eaves and gutter to stay within your land.

How we'd run your project

  1. Start at your house

    We come to your home in Llanidloes, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  2. Drawings, then consent

    We draw the scheme, check it against the rules in Wales, and take it through the right consent with the council.

  3. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  4. On site

    One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about two-storey side extensions in Llanidloes

Which postcodes do you cover around Llanidloes?

We cover Llanidloes (SY17, SY18 and SY19) and nearby places including Newtown, Llandrindod Wells and Builth Wells, plus the rest of Powys. The first site visit is free.

Do I need planning permission for a two-storey side extension in Llanidloes?

Llanidloes is in Wales, so Wales planning rules apply. Can be permitted development in Wales if it is 10.5 m from the side boundary, set back 1 m from the front and doesn't widen the house by more than half; otherwise planning permission. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How long does a two-storey side 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.

How much does a two-storey side extension cost in Llanidloes?

Our guide for Wales, which covers Llanidloes, is £1,890–£2,530 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £79,000–£106,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

Close to Llanidloes? We work across the area, including:

Other extensions in Llanidloes

All two-storey extension services in Llanidloes · Two-storey side extensions across Powys

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Llanidloes.

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