Physical address:
128 City Road, EC1V 2NX, London,UK
Loft Conversion Cost London 2026 | Complete Pricing Guide
How Much Does a Loft Conversion Cost in London in 2026?
A loft conversion remains one of the best investments you can make in your London property. By converting unused roof space into a habitable room, you can add significant living area and property value without sacrificing any garden space. This guide provides detailed pricing information for loft conversions in London in 2026.
Average Loft Conversion Costs by Type
The cost of a loft conversion depends primarily on the type of conversion you choose. Here are the typical price ranges for London in 2026:
- Velux (rooflight) conversion: £20,000 to £35,000 – The most affordable option, using existing roof structure with new skylights
- Dormer conversion: £35,000 to £60,000 – The most popular choice, creating full-height living space with a box-shaped extension to the roof
- Hip-to-gable conversion: £40,000 to £65,000 – Extends the sloped side of the roof to create a vertical gable wall
- Mansard conversion: £50,000 to £75,000+ – The most extensive option, creating near-vertical walls for maximum space
- L-shaped dormer: £45,000 to £70,000 – Designed for Victorian terraced properties with rear outriggers
What Is Included in These Costs?
A professional loft conversion quote from Fixiz Ltd typically includes:
- All structural steelwork and timber framing
- New staircase to access the loft
- Insulation to meet current Building Regulations
- Electrical installation including lighting and sockets
- Plastering, skimming, and decoration
- Flooring
- Windows (Velux or dormer)
- Building Regulations application and inspections
- Scaffolding
Additional Costs to Consider
- En-suite bathroom: £3,500 to £8,000 additional
- Underfloor heating: £1,500 to £3,000 additional
- Juliet balcony: £1,000 to £2,500 additional
- Planning permission (if required): £500 to £1,000
- Structural engineer report: £300 to £600
- Party wall agreement: £700 to £1,500 per neighbour
Factors That Influence Loft Conversion Cost
Several factors affect the final price of your loft conversion:
- Conversion type: Mansard conversions cost significantly more than Velux due to the structural work involved
- Property type: Terraced houses may need party wall agreements, adding cost
- Roof condition: If the existing roof needs repairs before conversion, costs will increase
- Plumbing requirements: Adding an en-suite or wet room adds to the total
- Access and scaffolding: Properties with difficult access may incur higher scaffolding costs
- Finish level: Premium finishes, bespoke joinery, and high-spec fittings increase costs
How Much Value Does a Loft Conversion Add?
A loft conversion typically adds between 15% and 25% to your property value, depending on the type of conversion and the additional space created. In many North London boroughs, a well-designed loft conversion with an en-suite bedroom can add £50,000 to £100,000 or more to the property value, making it one of the highest-return home improvement projects.
How Long Does a Loft Conversion Take?
Typical timescales for loft conversions are:
- Velux conversion: 2 to 3 weeks
- Dormer conversion: 5 to 7 weeks
- Hip-to-gable: 6 to 8 weeks
- Mansard conversion: 8 to 12 weeks
Get a Free Loft Conversion Quote
At Fixiz Ltd, we provide fixed-price quotes for all types of loft conversions across North London. Our transparent pricing means no hidden extras. Contact us today for a free consultation and detailed quote for your loft conversion project.
Call us: 020 XXXX XXXX | Email: info@fixiz.co.uk