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Mansard Loft Conversions in London
A mansard replaces the back slope of the roof (and sometimes the front) with a near-vertical wall. It gives the most usable space of any loft conversion and is the type councils most often approve on period terraces in Central and West London.
Since 2013 · Fully insured · CSCS-carded, SMSTS-supervised · Free site visit and itemised written quote
What's included
Planning application and drawings
Structural design, steelwork and Building Control
Party Wall Act notices to neighbours
New roof structure, slate or tile finish, lead work and windows
Full internal fit-out: stairs, bathroom, electrics, decoration
Price and time on site
From £65,000 incl. VAT, typically 12–16 weeks on site.
Questions we're often asked
Does a mansard need planning permission?
Almost always. We prepare and submit the application before work starts.
Is a mansard worth it over a dormer?
On a terrace with a shallow roof, often yes. It can give a full extra floor rather than one room.
Other loft conversions services
Hip-to-gable loft conversions · Velux loft conversions · Loft en-suites · All loft conversions
Often done together
Period property renovation · Bespoke staircases · Loft en-suites
Back to all domestic services.
Get a free quote
Send us your postcode and a few photos, or call 020 7476 2770 / 07903 854379. We'll arrange a free site visit and send an itemised written quotation. Get a free quote
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