Velux Loft Conversion Plans & Drawings
A Velux conversion is the simplest, fastest and most affordable way to turn a loft into a usable room. The existing roof stays exactly as it is — we simply add Velux roof windows and design the interior to make the space habitable. We deliver Velux conversion drawings and planning across Essex, London and Hertfordshire.
- Cheapest conversion type
- Fastest to build (4–6 weeks)
- Almost always Permitted Development
- Minimal disruption to your home
- Ideal for bedrooms & home offices
- Fixed-price drawings package
Why homeowners choose Loft Plans
Drawings, structural calculations and planning submissions delivered as one fixed-price package — no hidden extras.
Recent projects
A recently completed L-shape dormer conversion in London — featuring Velux roof windows, a full master suite with en-suite, and a separate home office. Velux windows are used throughout to bring natural light into the new spaces.
How it works
- 1
Get in touch
Our surveyor visits your property to take detailed measurements and assess the conversion potential.
- 2
Draft Drawings
Receive your first draft plans within 7 days of the survey.
- 3
Planning Submission
We manage planning and building control applications, handling all queries with local authorities.
- 4
3D Visualisation (Optional)
Step into your loft design with our immersive 3D Virtual Tours — ideal if you want to visualise the space before fully confirming your layouts.
- 5
Structural Calcs & Building Regs
Once designs are approved, our engineers complete structural calculations and building regulation drawings within a few days.
- 6
Move to Construction
Once approved, your plans are ready for your builder to start the project.
Why choose a Velux loft conversion?
A Velux conversion keeps your existing roof line completely intact — no dormers, no hip-to-gable alterations, no scaffolding-heavy external works. We strengthen the floor, insulate the roof, add a staircase and fit Velux roof windows to bring natural light into the space. Because nothing extends beyond the existing roof profile, Velux conversions almost always qualify for Permitted Development, which means no full planning application. They're the cheapest and quickest loft conversion type — and for homes with enough existing head height, they're often the smartest choice.
When is a Velux conversion the right option?
Velux conversions work best when your loft already has good head height (at least 2.8m from joist to ridge — once the floor is built up and the roof insulated, the finished space ends up considerably smaller) and you don't need to maximise every inch of floor area. Typical use cases include: A spare bedroom or guest room where the sloped ceiling isn't a problem. A home office, studio or hobby room. A playroom or teenager's hangout. Properties in conservation areas where dormers aren't permitted. Homes where the owner wants to keep external disruption to an absolute minimum. If your loft is on the short side or you need a full-height double bedroom plus en-suite, a dormer conversion will usually deliver better results.
Velux vs dormer at a glance
| Conversion type | Typical build cost | Build timeline | Planning |
|---|---|---|---|
| Velux (rooflight) | £25,000–£30,000 | 4–6 weeks | Almost always Permitted Development |
| Dormer | £40,000–£45,000 | 6–8 weeks | Usually Permitted Development |
| Hip-to-gable | £45,000–£55,000 | 8–10 weeks | Usually Permitted Development |
| L-shape dormer | £45,000–£55,000 | 8–10 weeks | Often Permitted Development |
Build costs are indicative guides only — actual figures depend on size, spec and location.
Not sure which conversion suits your loft?
Get in touch — we'll measure up and tell you honestly what your roof can deliver.
Get in touchWhat's included in our Velux conversion package
Initial planning drawings showing the proposed layout, window positions and staircase, building regulations drawings covering insulation, fire safety and structural elements, structural calculations approved by a chartered engineer, Lawful Development Certificate application where useful, and full liaison with your local authority — all for a single fixed price with no hidden extras.
Velux vs dormer — which is right for you?
Velux conversions are cheaper, faster and less disruptive — but they don't add any floor area or head height. Dormers cost more and take longer, but typically deliver enough usable space for a double bedroom plus shower room. If you have generous head height and just want a comfortable extra room, Velux is hard to beat. If you need to maximise every square metre, go dormer. We'll advise honestly on the survey based on what your roof can actually deliver.
Areas we cover
We deliver Velux loft conversion drawings, structural calculations and planning applications across Essex, London and Hertfordshire — including:
Frequently asked questions
What is a Velux loft conversion?
A Velux (or rooflight) conversion is the simplest type of loft conversion. The existing roof structure stays exactly as it is — no dormers, no extensions — and Velux roof windows are fitted flush into the roof slope to bring light into the new room. It's the cheapest, quickest and least disruptive way to convert a loft.
Do I need planning permission for a Velux loft conversion?
In most cases, no. Because nothing extends beyond the existing roofline, a Velux conversion almost always falls under Permitted Development. The exceptions are conservation areas, listed buildings, and homes where Permitted Development rights have been removed. We'll confirm on the survey.
How much head height do I need for a Velux conversion?
You need at least 2.8m from the existing ceiling joists to the underside of the ridge. Once the floor is built up and the roof is insulated, the finished head height drops significantly — so the raw loft has to start tall enough to leave a usable room behind. If you're short on head height, a dormer is usually the better option.
How long does a Velux loft conversion take to build?
Velux conversions are the fastest type — typically 4–6 weeks on site once construction starts. The design, structural calculations and building regulations approval phase takes around 6–8 weeks before the build can begin.
How much does a Velux loft conversion cost?
Velux conversions are the most affordable loft conversion type because no structural roof alteration is required. Build costs typically fall between £25,000–£30,000 depending on size, spec and location — usually 30–40% lower than a dormer of the same footprint. Our drawings and planning package is a separate fixed price — planning drawings from £950, full package from £1,500.
Can I have a bedroom or bathroom in a Velux conversion?
Yes — provided you have the head height. Velux conversions work brilliantly as bedrooms, home offices or playrooms. Bathrooms are possible but the sloped ceiling limits where you can position a shower, so layout planning matters.
Ready to start your loft conversion?
Get in touch and receive your first draft drawings within 7 days.
Get in touch