What is a hip-to-gable loft conversion?

A hip-to-gable loft conversion replaces the sloping side (the hip) of a semi-detached or detached roof with a vertical gable wall. This extends the ridge and creates enough space for a staircase and a full-size room, usually combined with a rear dormer.
How much does a hip-to-gable loft conversion cost in Dartford?
In Dartford, a hip-to-gable loft conversion typically costs £61,500–£87,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Building costs in the South East run about 12% above the UK average, and the figures for Dartford are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A hip-to-gable with rear dormer | £61,500–£87,500 |
| Higher specification | £87,500–£109,500 |
What moves the price most:
- Size of the rear dormer
- Bathroom and plumbing
- Gable wall construction and finish
- Roof tile matching
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a hip-to-gable loft conversion in Dartford?
Here is how the rules work for a hip-to-gable loft conversion in England. In England a hip-to-gable conversion is often permitted development within the 50 cubic metre roof volume limit for semi-detached and detached houses, provided the gable does not face a road and the house is not in a conservation area.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
What we take care of:
- Gable wall built in brick or block and finished to match
- Staircase and fire-safe escape route
- Roof extension and rear dormer
- Building control sign-off
- Survey and planning check
- Drawings and structural calculations
How long does it take?
The build itself usually takes 7 to 10 weeks on site. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Dartford
The South East has a broad mix of housing, from Victorian terraces in the towns to post-war semis and newer estates, so extension types vary street by street.
We work across Dartford and neighbouring areas such as Erith, Bexleyheath and Swanley. Postcodes we cover in Dartford include DA1.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about hip-to-gable loft conversions in Dartford
How much does a hip-to-gable loft conversion cost in Dartford?
In Dartford, a hip-to-gable loft conversion typically costs £61,500–£87,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Do you build hip-to-gable loft conversions in Dartford?
Yes. We build hip-to-gable loft conversions across Dartford, including postcodes DA1. Every project starts with a free home visit.
Is a hip-to-gable conversion permitted development?
Often yes in England, within the 50 cubic metre roof volume limit for semi-detached and detached houses. It is not permitted development in conservation areas or where rights have been removed.
How long does it take?
Typically 7 to 10 weeks on site.
Can the gable be brick?
Yes. We match the existing finish, whether brick, render or pebbledash.
