Gwynedd house extensions

Towns we cover in Gwynedd

Towns we cover here include Bangor, Gwynedd, Caernarfon, Holyhead, Llangefni.

• Bangor, Gwynedd
• Caernarfon
• Holyhead
• Llangefni

Planning and building control in Gwynedd

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 regulations approval is separate from planning. Wales has its own building regulations and approved documents; the council or a registered building control approver checks the plans, inspects the work and issues a completion certificate.

Gwynedd extension prices at a glance

We publish guide prices so you can budget before anyone visits. For Gwynedd they are adjusted by ×0.93, the factor we use across Wales.

Which extension suits a Gwynedd home?

In Wales, terraced houses with rear offshoots are common in the towns, while detached houses and bungalows dominate in rural areas.

Start by comparing bungalow extensions, side return extensions and pitched roof extensions: between them they cover most of the layouts we see requested for houses like these.