Is a timber frame extension cheaper than a traditional brick extension?

Usually yes — both in materials and build time. Per-square-metre rates are typically £100–£200/m² cheaper, and the build programme is weeks shorter. The saving comes from the factory-made frame and faster on-site erection.

Do I need planning permission for a single-storey extension?

Often no, under permitted development. Rear single-storey extensions up to 3m (semi/terrace) or 4m (detached) usually qualify, extendable to 6m/8m under prior approval. Conservation areas and listed buildings are different — we confirm for your specific property.

What if my house is in a conservation area?

Permitted development rights don't apply in conservation areas, which cover a large part of Bath. You'll need a formal planning application. We can work with your architect on designs that satisfy conservation requirements.

How long does a timber frame extension take from start to finish?

Typical single-storey extension: 8–12 weeks on site after frame delivery, plus 4–8 weeks factory lead time before that. Total 12–20 weeks. Add time at the front if planning permission is needed.

Bath · Timber Extensions by city

Timber Extensions in Bath

Timber frame extensions — typically cheaper and faster than traditional blockwork, with the same building-regs compliance. TM Carpentry handles the structural carpentry side: frame, roof structure, sheathing and external cladding. Building regs apply regardless of construction method, and Bath has a lot of conservation-area properties where permitted-development rights don't apply. Available across Bath, Bristol and Keynsham — see the areas covered for specific neighbourhoods.

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What's included

Every timber extensions job covers the items below — always. The exact specification depends on your space and what you want it to do.

Timber frame construction
Roof structure (cut and truss)
Sheathing and breathable membrane
External cladding or render carrier
Internal studwork and first-fix carpentry
Coordination with bricklayer / groundworker trades

About timber extensions in Bath

What timber extensions typically look like in Bath

Bath timber extensions typically work within the Bath World Heritage Site and Bath Conservation Area, which means most extensions need a planning application rather than relying on permitted development. Most Bath extensions are smaller than Bristol's — typically single-storey rear extensions of 3–4m depth on Georgian and Victorian terraces, or side-return knock-throughs on Victorian semis. Tom works with B&NES Conservation Officer expectations where the extension is in a visible position from the street.

Honest note: The descriptions below are generalisations — what's typical or commonly found across Bath's neighbourhoods. Every property is different, so Tom will always confirm what's actually there on the site visit before quoting.

Planning & permissions

The planning context in Bath

Most residential streets in Bath fall within the Bath World Heritage Site and many are within the Bath Conservation Area. Permitted Development rights for extensions are heavily restricted — PD allows only a single-storey rear extension up to 3m (or 4m for a detached house) without neighbour consultation, and only if it's not forward of the principal elevation. Most useful Bath extensions (4m+, two-storey, side-return on a corner plot) need a full planning application with B&NES, especially if the extension is in a visible position or on a listed building. Listed Building Consent is required for any extension to a Grade II listed property. Building Regulations apply to all extensions regardless of size or construction method. Tom will tell you what's needed on the site visit before any work starts.

Common timber-extension patterns in Bath

Common Bath timber extension patterns: 3–4m single-storey rear extensions on Georgian and Victorian terraces (sized to fit the rear garden without overpowering the original building), 3m side-return extensions on Victorian semis (knock-through the side passage to widen the kitchen), occasional two-storey rear extensions on Victorian villas where the plot is deep enough, and (rarely) full-width rear extensions on the bigger detached houses in Oldfield Park, Larkhall and Weston. Most Bath extensions are clad in timber (larch or cedar) or render carrier to match Bath stone context — Bath stone replication is rare but possible for matching neighbouring properties. Most jobs require a structural engineer (loads + foundation design), and almost all need a planning consultant for the application.

Areas in Bath