Loft Conversion Cost calculator

Five questions, a realistic range in under a minute. Built from real Fox Conversions jobs across Essex, no email address needed.

Step 1 of 5 20%
Step 1 of 5

What type of loft conversion?

Not sure? Pick the closest, I'll confirm at survey.

Converting a garage instead?
Step 2 of 5

How much head height is there?

Stand in the middle of the loft, under the ridge. This decides whether a conversion works at all.

Straight answer on low head height: under 2.0m at the ridge, a full conversion is hard and sometimes not possible without lifting the roof. Modern PIR insulation can claw back 40 to 50mm compared with older methods, which is occasionally the difference. I'll tell you honestly at survey if it isn't viable.
Step 3 of 5

What shape is the roof?

Look from the street. Most 1930s Essex semis are hipped, sloping on all four sides.

Step 4 of 5

Do you want an en-suite?

Plumbing and a shower room add cost, and add a lot to the room.

Step 5 of 5

How far do you want it taken?

The workmanship is the same on every job. This is about what's in scope.

Step 1 of 2

What size is the garage?

Size drives most of the cost.

Converting a loft instead?
Step 2 of 2

Will it need a bathroom or WC?

Plumbing is the biggest variable in a garage conversion.

Your estimated cost

That's a range, not a quote. Your house decides where in it you land, and I'd rather see it than guess. Send me the details and I'll reply with a breakdown and a nearby job at a similar price.

Send me the breakdown on WhatsApp

Opens WhatsApp with your answers filled in. I reply myself, usually the same evening.

or call Chris on 07441 343232

What's included in this estimate
Loft en-suite bathroom in Rayleigh by Fox Conversions
En-suite in the loft Β· Rayleigh
Finished loft bedroom in Leigh-on-Sea
Finished bedroom Β· Leigh-on-Sea
Three small dormers on a long roof in Billericay
Three dormers, no tin roof Β· Billericay
Loft conversion under construction in Eastwood, Southend
Mid-build, steels and joists in Β· Eastwood

All Fox Conversions jobs. More on the completed projects page.

Two real jobs, so you can see where the range comes from

The calculator is built from jobs like these. Same houses, same roads, same 1930s roofs most of Essex has.

Hip-to-gable loft conversion with rear dormer in Leigh-on-Sea
Leigh-on-Sea, 1930s semi

Hip-to-gable with rear dormer and a new clay roof

Around Β£75,000 today

Hipped roof turned into a full gable, rear dormer, en-suite, and the whole roof re-covered in clay tiles while the scaffold was up. The roof on its own was about Β£8,000 of that.

See the Leigh job
Finished loft conversion bedroom in Billericay
Billericay, semi

Rear dormer, bedroom and en-suite

Around Β£55,000, drawings included

A straightforward dormer on a semi. A Billericay bungalow with the same spec comes in closer to Β£70,000 because the floor area is bigger and the steels are longer.

See the Billericay jobs

Why it's a range and not a number

Four things move a loft price more than anything else. I check all four at the survey.

SteelsEvery loft needs them. Span, how many, and whether they go in through the roof or up the stairs changes the price by thousands.Typically Β£3,000 to Β£8,000
BathroomAn en-suite means plumbing, a soil stack route, tiling and fittings. Where the existing bathroom sits decides how hard that is.Typically Β£6,000 to Β£10,000
Roof conditionIf the tiles and felt are tired, now is the cheapest moment to replace them because the scaffold is already there.About Β£8,000 for a new clay roof
Staircase positionThe new stairs have to land somewhere. A clean run over the existing stairs is simple. Stealing space from a bedroom is not.Can swing the price either way

Why Choose Fox conversions

15+ Years Local Experience
40+ Loft Conversions Completed
45 Positive CheckaTrade Reviews
Full Start-to-Finish Service

All projects personally managed by Chris Fox. Find out more about how we work.

Why Choose Fox Conversions for Your Loft Conversion

"Trusted local loft conversion specialists in Essex"
Before
After
  • Owner-led projects – You deal directly with me from quote to completion.
  • Fixed-stage payments – Pay only as each phase is complete.
  • Clean, respectful sites – Dust sheets, extraction and a daily tidy-up are standard.
  • The same trusted trades for over six years – carpentry, electrics, plumbing and plastering.
  • Loft Conversion Specialists – 5-star reviews on Google, Checkatrade and Houzz show the standard we keep.

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Read them all before making any decisions. We've got nothing to hide.

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Fox Conversions Ltd

Specialists in high-end home transformations for over 15 years.

Office: 9 Dorothy Gardens, Benfleet, Essex, SS7 3AD Phone: 07441 343232

Email: contact@foxconversions.com

Registered in England & Wales: Company No. 09270847

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