Warning: Our Portsmouth loft conversions are so comfortable, your guests might never want to leave your new spare bedroom!
Get Your Free Portsmouth QuoteSee what your Portsmouth neighbours say about our loft conversion work.
"I used to hit my head on the rafters. Now I can do jumping jacks in my new Portsmouth bedroom. Incredible transformation."
"Fantastic loft conversion in our Portsmouth home. The team was professional, tidy, and finished on time. Our new master bedroom with ensuite is stunning."
"Professional service from start to finish. Our hip-to-gable conversion has added so much space to our Portsmouth home. Quality workmanship."
"The structural work was done quickly and safely. As a Portsmouth local, I appreciated their knowledge of local planning rules."
"Honest, reliable and skilled. Our mansard loft in Portsmouth looks incredible. They finished exactly on budget."
"If you want a loft in Portsmouth, just book these guys. Seriously. Don't waste time with anyone else. Building Group is the real deal."
See more genuine Portsmouth customer reviews and loft conversion project galleries.
Read More ReviewsTransform your Portsmouth property's unused loft space into beautiful, functional living areas with our professional loft conversion services. Whether you need an extra bedroom, home office, or playroom in Portsmouth, we create bespoke solutions tailored to your lifestyle.
Our experienced Portsmouth team handles every aspect of your loft conversion project. From initial design and planning permission through to final decoration, we ensure your Portsmouth conversion maximizes space, natural light, and property value.
Choose the perfect conversion type for your Portsmouth property to maximize space and value
The most cost-effective option for Portsmouth properties using roof windows for natural light. Perfect for Portsmouth homes with adequate headroom.
Add valuable floor space and headroom to your Portsmouth property with single or multiple dormers. Popular choice in Portsmouth for space optimization.
Transform sloping hip roofs into vertical gable walls in your Portsmouth home, significantly increasing usable floor space. Ideal for Portsmouth semi-detached properties.
The premium option for Portsmouth properties creating maximum space with near-vertical walls. Perfect for period properties in Portsmouth.
Your Portsmouth property needs minimum 2.3m headroom at the highest point and sufficient floor area for conversion. Our Portsmouth specialists provide free assessments to determine if your loft is suitable and advise on the best conversion type for your Portsmouth property and budget. Most Portsmouth conversions fall under permitted development rights, but we handle all planning and building regulations applications where required.
Most terraced and semi-detached homes in Portsmouth have a 40-50 cubic meter allowance for roof extensions without full planning permission. We handle all Lawful Development Certificate applications for you.
Every conversion we build is inspected by approved inspectors to ensure compliance with Part B (Fire Safety) and Part L (Insulation) of the building regulations specific to Portsmouth housing stock.
Living in a terraced or semi-detached house in Portsmouth? We manage the Party Wall Notice process with your neighbors to ensure works can start on time.
Comprehensive evaluation of your Portsmouth loft space, structural assessment, and advice on the best conversion type for your property.
Architectural drawings, 3D visualizations, and planning permission applications for Portsmouth properties. We handle all regulatory approvals.
Steel beam installation, floor strengthening, and staircase construction by qualified Portsmouth engineers.
Velux roof windows, dormer construction, and window installations to maximize natural light in Portsmouth homes.
Complete bathroom installations including plumbing, electrical work, and luxury fixtures in your Portsmouth loft.
Plastering, decorating, flooring, and interior design services to create beautiful Portsmouth living spaces.
Professional space assessment
Architectural drawings and approvals
Professional loft specialists
Professional loft conversions throughout Portsmouth city centre, including period properties, modern homes, and conservation areas requiring specialist Portsmouth planning expertise.
Expert loft conversion services across all Portsmouth suburban areas. Specializing in semi-detached, detached, and terraced properties throughout Portsmouth.
Specialist conversions for Portsmouth's Victorian, Edwardian, and period properties. Sympathetic designs maintaining character while maximizing space.
Expert handling of Portsmouth conservation area requirements. We navigate planning restrictions and create beautiful conversions that comply with local regulations.
Portsmouth Loft Conversions Completed
Average Portsmouth Customer Rating
Years Serving Portsmouth
Portsmouth Building Control Approved
With over 15 years of experience in Portsmouth, we understand local planning requirements, building regulations, and architectural styles. Our Portsmouth team delivers exceptional loft conversions that enhance your property value.
Hip-to-gable conversion creating master bedroom with ensuite in a Victorian Portsmouth terrace. Added 30sqm of living space.
Project Value: £48,000
Dormer loft conversion in modern Portsmouth semi-detached. Created two bedrooms and bathroom for growing family.
Project Value: £42,000
Mansard conversion in Portsmouth conservation area. Luxury master suite with dressing room and ensuite.
Project Value: £65,000
"I used to hit my head on the rafters. Now I can do jumping jacks in my new Portsmouth bedroom. Incredible transformation."
- Joseph Clark, Portsmouth
"Fantastic loft conversion in our Portsmouth home. The team was professional, tidy, and finished on time. Our new master bedroom with ensuite is stunning."
- Olivia White, Portsmouth
"Professional service from start to finish. Our hip-to-gable conversion has added so much space to our Portsmouth home. Quality workmanship."
- Mark Thompson, Portsmouth
Loft conversion costs in Portsmouth vary based on type, size, and specifications. Typical Portsmouth prices: Velux conversions £20,000-£30,000, Dormer conversions £35,000-£45,000, Hip-to-gable £40,000-£55,000, Mansard conversions £45,000-£65,000. All Portsmouth quotes include structural work, insulation, electrics, plastering, and building control fees. Contact us for a free Portsmouth survey and detailed quote.
A transparent guide to typical conversion costs in the Portsmouth area (2025 Estimates)
| Conversion Type | Suitability | Timeframe | Price Range |
|---|---|---|---|
| Velux (Roof Light) | Existing headroom > 2.3m | 4-6 Weeks | £20k - £30k |
| Dormer (Rear) | Semis & Terraces | 6-8 Weeks | £35k - £50k |
| Hip-to-Gable | End-terrace & Semi-detached | 8-10 Weeks | £45k - £60k |
| Mansard | Period Properties / London Styles | 10-12 Weeks | £50k - £75k+ |
*Prices are indicative for Portsmouth properties and subject to survey.
Senior Structural Specialist
"I oversee all loft conversions in the Portsmouth area. My job is to ensure your project meets local building regulations while maximizing every inch of space. I'm happy to visit your property for a preliminary structural assessment."
Four recent loft conversions across the UK — from a London mansard within a conservation area to an L-shaped Manchester dormer, a Birmingham hip-to-gable, and a Leeds rear dormer. Tap any project for the full case study.
Loft
Mansard loft conversion on a London Victorian terrace within a conservation area — full mansard build raising the rear roof line, slate-clad cheeks to match the neighbours, two double bedrooms with private en-suites, and a sky-lit landing. Approval secured under full planning, not Permitted Development.
Loft
L-shaped rear dormer loft conversion on a Victorian terrace — turning unused roof space into two double bedrooms and a shared en-suite, with two Velux windows to the front, a glass balustrade to the new staircase, and matching slate-grey finish to blend with the original roof.
Loft
Rear dormer loft conversion turning unused roof space into a master bedroom and en-suite, with two Velux roof windows to the front and a slim glass balustrade to the new staircase.
Loft
Hip-to-gable conversion with rear dormer on a 1930s semi-detached — squaring off the original hipped roofline to gain full standing headroom, creating a master bedroom with built-in wardrobes and a generous en-suite, plus a third Velux to the front for natural light.
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View All Case StudiesFrom planning permission to the final coat of paint, we handle it all. Start your Portsmouth project now.
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