Dormer loft conversions in Northallerton

Covering Northallerton

Northallerton sits 30 miles north-west of York, with Darlington 14 miles to the north and Thornaby-on-Tees 14 miles to the north.

Homes in Yorkshire and the Humber

Stone-built terraces are typical of many West Yorkshire towns, while red brick dominates in Hull and much of South Yorkshire, so matching materials is a big part of designing an extension here.

What goes into a dormer loft conversion?

A dormer loft conversion builds a box-shaped extension out from the rear slope of the roof, creating vertical walls and full head height across most of the new floor. It is the most popular type of loft conversion because it gives the most usable space for the cost.

Lawful development certificate or planning drawings
Dormer frame, roof covering and cladding
Staircase, insulation and plasterboard

How much should I budget for a dormer loft conversion?

Typical ranges for dormer loft conversions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

Dormer loft conversions	Guide price incl. VAT
Rear dormer, bedroom only	£50,000 to £65,000
Full-width dormer with en-suite	£60,000 to £80,000
L-shaped dormer (over rear outrigger)	£65,000 to £90,000

Planning and building rules in Northallerton

Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.

In England many loft conversions are permitted development: the extra roof volume must stay within 40 m³ on a terraced house or 50 m³ on a semi or detached house, nothing can sit higher than the existing ridge, no dormer can face a road on the main elevation, and side windows must be obscure-glazed and non-opening below 1.7 m.

What should I think about before starting?

A flat dormer roof needs proper falls and a quality membrane.
L-shaped dormers are common on Victorian terraces with a rear outrigger.

How does the project run?

Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

What people ask before starting

Is a dormer permitted development?

Rear dormers in England often are, within the 40 m³ (terrace) or 50 m³ (semi or detached) volume allowance. Front dormers facing a road are not.

What cladding can a dormer have?

Tile-hanging to match the roof, render, slate, timber or zinc, depending on the house and any planning conditions.

Do you work in Northallerton?

Yes. Northallerton is within our coverage for dormer loft conversions, along with nearby Darlington and Thornaby-on-Tees.

Also covering

Learn more about dormer loft conversions, or see every project we cover in Northallerton.