Add a full master bedroom, en-suite or home office without moving house. Ridgeline designs, structures, builds and finishes your dormer loft conversion to a turnkey standard — fixed quote, single team, no surprises.
5★ rated · Fully insured · Free site visit within 1 working day
15+
Years on the tools
100+
Projects delivered
5★
Bark client rating
1 Day
Quote turnaround
Family
Run since 2016
Service Overview
A dormer loft conversion takes the dead, sloping space at the top of your house and converts it into a full-height, fully usable storey. We extend the existing roof outwards with a flat-roof or pitched-roof dormer, install proper structural support, insulate and ventilate to current Building Regulations, and finish the room to a 'walk-in-and-enjoy' standard. The result is the most affordable square metre you'll ever add to your property — typically delivering a new master bedroom with en-suite, a generous home office, or a self-contained guest suite.
Most semi-detached and terraced homes across Greater Manchester, Lancashire and Merseyside are ideal candidates for a dormer. The dormer extension increases head height across a much larger floor area than a Velux-only conversion, which means you actually get a usable room rather than an awkward attic with sloping walls eating half the footprint.
Ridgeline delivers your dormer as a true turnkey project. That means structural calculations, steelwork, dormer construction, roofing, windows, insulation, plastering, first and second-fix carpentry, electrics, plumbing, decoration and floor covering — all coordinated by a single team. You don't manage trades, chase suppliers, or get caught between subcontractors blaming each other.
Because we are family-run, you deal directly with Alex from the first site visit through to the final handover. The same hands quoting your project are the same hands building it.
The cost of getting it wrong
A dormer loft is a structural project. Done properly, it adds value for decades. Done badly, it leaks, sags, fails Building Control, and costs more to remediate than the original build.
Cheap quotes often skip proper structural engineering. The result is sagging floor joists, cracking ceilings below, and a room that fails Building Control sign-off.
Skimped insulation and missing vapour control turn your new room into a cold, damp space that grows mould within two winters.
The dormer cheeks, flashings and box-gutters are where amateur builds fail. Water tracks invisibly into the ceiling below for months before you see it.
Without proper Building Regs sign-off, you cannot legally market the room as a bedroom — and your buyer's solicitor will flag it on sale.
Multiple uncoordinated trades mean delays, blame-shifting, and a finish that looks 'almost' right everywhere you look.
'Day rate' quotes balloon mid-build. Fixed, itemised quotations protect you from £5–10k of surprise extras.
Our Process
We measure, assess head height, check structure, and discuss what's realistic for your property.
Detailed drawings, structural specification, written itemised quotation and clear timeline.
We coordinate with structural engineers, architects and Building Control on your behalf.
Structure, dormer, roofing, insulation, plastering, electrics, decoration — single trusted team.
Snag-free walkthrough, Building Regs certificate, and a phone line that still answers after handover.
The Benefits
Not a cramped attic — a full-height room you'll actually use every day.
Loft conversions consistently outperform other extensions on £-per-£ ROI in the North West.
Most dormers are watertight within 2–3 weeks and finished inside 10. You stay in your home throughout.
Every project is signed off by Building Control, with paperwork you can hand to a buyer's solicitor.
We hand you a finished, decorated, carpeted room — not a shell to finish yourself.
Speak to Alex directly. No call centre, no project manager you've never met.
Recent Work
Every photo below is from a Ridgeline project — no stock imagery, no staged shots.
In detail
Not every loft is the same. Roof pitch, head height, party walls and the original construction all change what's possible — and what it costs. Here's what we look at, and the options we'll talk through with you on your free site visit.
We build the right dormer for your roofline — never a one-size answer.
Existing rafters and ceiling joists rarely meet modern loadings. We design proper steel beams, engineered timber joists and load-bearing posts so the new floor is rock solid and your existing ceilings stay crack-free.
We exceed current Approved Document L U-values using a combination of PIR insulation between and over rafters, with vapour control layers correctly lapped. Your loft will be warmer in winter and cooler in summer than any other room in the house.
Loft stairs must comply with strict head-height, pitch and protected-route requirements. We design the stair early so it works with your existing layout — not as an afterthought.
Dormer windows, Velux roof windows, Juliet balconies and trickle vents are all coordinated to maximise daylight and meet ventilation regs. We'll show you light studies on the design.
Most rear dormers fall under Permitted Development, but volume, materials and front-facing changes can require full planning. We handle the entire application or Lawful Development Certificate on your behalf.
FAQs
Can't see your question? Call Alex directly on 07368 183733 or request a free estimate.
Most full turnkey dormer conversions in Greater Manchester and Lancashire range from £45,000 to £75,000+ depending on size, finish, en-suite inclusion and roof complexity. Every Ridgeline quote is fixed, written and itemised — no day rates and no mid-build surprises.
A typical dormer loft conversion takes 6–10 weeks from first lift to handover. We make the loft watertight within the first 2–3 weeks so disruption to the rest of your home is minimal.
Most rear dormers fall within Permitted Development rights, meaning no full planning application is needed. We'll confirm this for your specific property on the free site visit, and apply for a Lawful Development Certificate if appropriate.
Yes. Building Regulations approval is mandatory for any loft conversion. We coordinate with Building Control inspectors throughout the build and hand you the completion certificate at handover.
Yes, in almost every case. The first phase is largely outside the existing living space, and once the loft is sealed we work above you. We protect carpets, dust-sheet routes and clean down daily.
Yes. Our workmanship is guaranteed and all major materials carry manufacturer warranties — typically 10 years on roofing membranes and 25 years on insulation.
Built to current Building Regulations standards with quality materials, a properly constructed dormer loft conversion will last the lifetime of the host building — 60+ years with normal maintenance.
Not always. For straightforward Permitted Development dormers we can produce drawings in-house. For more complex or character properties we work with trusted architects we recommend.
Across Greater Manchester, Merseyside, Lancashire, Cheshire, West & North Yorkshire, Derbyshire, Staffordshire and into Greater London for larger projects.
Call 07368 183733 or request a free estimate online. We'll arrange a no-obligation site visit at a time that suits you and have your fixed quotation back within a working week.
Related services
Speak directly with Alex — the owner — for a free, no-obligation estimate. Most quotes returned within one working day.
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Find us
Family-run from Aspull, Wigan — covering the wider North West.
