Loft Conversion Glasgow | Dormer, Velux & Hip-to-Gable Specialists

Types of Loft Conversion We Build in Glasgow

Velux / Rooflight Loft Conversion — from £15,000

The most affordable option — Velux windows are fitted into the existing roof slope without altering the structure, so no planning permission is required in most cases. You need a minimum of 2.2–2.4m head height from floor joist to ridge. Velux conversions work best on houses with a steep pitch (35°+), common across Bearsden, Newton Mearns and Giffnock’s 1930s–50s detached stock. Ideal for a home office, single bedroom or hobby room. Build time: 4–6 weeks.

Rear Dormer Loft Conversion — from £25,000

The most popular type in Glasgow. A dormer extends vertically out of the existing rear roof slope, adding both headroom and usable floor area. A rear dormer on a standard house typically qualifies as permitted development under Class 1D of the General Permitted Development (Scotland) Order — no planning permission required. A well-designed rear dormer creates a full double bedroom with en suite, the most common request we receive in Newton Mearns and Clarkston. Build time: 6–10 weeks.

Hip-to-Gable Loft Conversion — from £30,000

Detached or end-of-terrace homes with a hipped (sloping) gable end can gain significant extra space by converting the hip to a vertical gable wall, often combined with a rear dormer. Common in 1930s–1960s detached properties across Newton Mearns, Giffnock and Bearsden. A hip-to-gable changes the external silhouette and typically requires full planning permission. Build time: 8–12 weeks.

Mansard Loft Conversion — from £40,000

A mansard involves rebuilding most or all of the roof structure with near-vertical walls and a flat or shallow-pitched top — maximum headroom and floor area, most complex and expensive type. Almost always requires full planning permission. More common in large Victorian properties in Glasgow’s West End and Southside. Build time: 12–16 weeks.

Loft Conversion Cost Glasgow 2025–26

Type	From	Mid-Range	High Spec	Time
Velux	£15,000	£18,000–22,000	£25,000+	4–6 wks
Rear Dormer	£25,000	£30,000–42,000	£50,000+	6–10 wks
Hip-to-Gable	£30,000	£40,000–55,000	£65,000+	8–12 wks
Mansard	£40,000	£50,000–65,000	£70,000+	12–16 wks

All prices include VAT. En suite addition: £5,000–£12,000 extra. Structural engineer calculations: ~£300–£500.

What’s Included in Our Fixed Price

• Building warrant application to Glasgow City Council Building Standards
• Structural engineer calculations
• New floor joists and subfloor (47×220mm C24 joists at 400mm centres)
• Dormer structure or rooflight installation
• Rigid PIR insulation (Celotex/Kingspan) between and below rafters plus acoustic mineral wool to floor
• Vapour control layer, plasterboard and skim finish throughout
• New staircase from first floor to loft
• First and second fix electrics (sockets, lighting, smoke alarm)
• VELUX or equivalent roof windows with flashing kit
• Completion certificate from Glasgow City Council

Planning Permission & Building Warrant — Scotland’s Rules

Planning Permission in Scotland

Loft enlargements fall under Class 1D of the General Permitted Development (Scotland) Order, updated by Planning Circular 1/2024. Unlike England, Scotland has no volume limit (England’s 40m³/50m³ rules do not apply here). A rear dormer must: not exceed the existing ridge height; be no wider than half the roof plane at the eaves; be at least 300mm from any roof edge; and not face a road. Most rear dormers on standard Glasgow houses qualify as permitted development. Front dormers, hip-to-gable and mansard almost always need full planning permission. Flats and conservation area properties have no permitted development rights.

Building Warrant (Always Required)

Regardless of planning permission, a building warrant from Glasgow City Council Building Standards is legally required under the Building (Scotland) Act 2003 for all structural loft work. Starting without a warrant is a criminal offence. On completion, the council issues a completion certificate — essential for selling your home. We handle the full warrant application and completion inspection as part of every project.

Conservation Areas

Glasgow has 25 conservation areas including the West End, Hyndland, Pollokshields and parts of Bearsden and Milngavie town centres. In conservation areas, permitted development for roof alterations is removed — even a rear dormer needs full planning permission. We check your property’s conservation status at survey stage before committing to a programme.

Is My Loft Suitable?

• Head height: At least 2.2–2.5m from floor joist to ridge for 2m stair clearance
• Roof pitch: 30° or more ideal; below 25° may need a dormer for adequate headroom
• Roof structure: Traditional cut roofs (pre-1970s) are easiest; modern trussed rafters need extra structural work
• Floor joists: Existing ceiling joists are never strong enough — new structural floor joists always fitted
• Staircase route: Usually requires losing a cupboard or part of a bedroom — designed at survey stage

Our Process

1. Free survey and fixed-price quote — We visit, measure and quote in writing. No obligation.
2. Structural engineering and warrant — Engineer calculations lodged with Glasgow City Council; warrant granted before work starts.
3. Structural work — Floor joists, roof structure, dormer or rooflights. Weathertight before interior work begins.
4. First fix — Electrics, plumbing for en suite if included.
5. Insulation and plasterboard — PIR between rafters, mineral wool to floor, skim finish throughout.
6. Second fix and finishing — Staircase, joinery, sockets, lighting, flooring, decoration.
7. Completion certificate — Council inspection and sign-off. Paperwork issued to you.

Areas We Cover

We carry out loft conversions across Glasgow and the surrounding suburbs. Recent projects include:

• Newton Mearns — Detached 1960s–80s properties, often ideal for rear dormer or hip-to-gable
• Bearsden — 1930s–50s sandstone semis with steep pitches, Velux or dormer
• Giffnock — Post-war detached and semi-detached, good pitch
• Clarkston — Mixed 1930s–60s housing, strong demand for bedroom lofts
• Milngavie — Detached properties, often hipped roofs needing hip-to-gable
• Pollokshields — Victorian sandstone (conservation area checks always done)
• Shawlands and Southside — Terraced and semi-detached stock
• West End Glasgow — Tenements and villas (conservation area rules apply)

Frequently Asked Questions