What is a mansard loft conversion?
A mansard loft conversion rebuilds the roof with a nearly vertical slope (about 72 degrees) and a flat top, effectively adding a new storey. Small dormer windows sit within the steep slope. Mansards are common on period terraces in towns and cities.
How much does a mansard loft conversion cost in Perth?
In Perth, a mansard loft conversion typically costs £63,000–£92,000 for a typical rear mansard, including VAT at 20% (standard rate). Prices in Scotland sit near the national average for this kind of work, and the range for Perth reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rear mansard | £63,000–£92,000 |
| Higher specification | £92,000–£115,000 |
What moves the price most:
- Scaffolding on busy streets
- Front, rear or both
- Bathrooms and finishes
- Roof covering: natural slate costs more
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a mansard loft conversion in Perth?
Whether you need planning permission depends on your house and its location in Scotland. In Scotland a mansard needs planning permission and a building warrant.
In Scotland a building warrant is needed before work starts on most extensions, loft conversions and conversions. It is issued by the council’s building standards service. When the work is finished, a completion certificate is submitted and accepted by the council after inspection.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
Handled as part of most mansard loft conversions:
- Planning drawings and application
- Building control sign-off
- Insulation, electrics, plumbing and plastering
- New roof structure, slate or tile covering and lead work
- Written agreement with neighbours on shared walls
- Structural design and calculations
How long does it take?
Allow 9 to 12 weeks on site, after planning approval. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Perth
In Scotland, bungalows and one-and-a-half-storey homes are common, so dormer conversions are a popular way to add bedrooms.
If your home is in Perth or close by in Cupar, Glenrothes and Dundee, a free home visit is the first step.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about mansard loft conversions in Perth
How much does a mansard loft conversion cost in Perth?
In Perth, a mansard loft conversion typically costs £63,000–£92,000 for a typical rear mansard, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Do you build mansard loft conversions in Perth?
Yes. We build mansard loft conversions across Perth, including postcodes PH1. Every project starts with a free home visit.
Do I need planning permission for a mansard loft conversion in Perth?
In Scotland a mansard needs planning permission and a building warrant.
Why choose a mansard over a dormer?
A mansard gives more usable floor space and a neater appearance from the street, but costs more and needs planning permission.
Can I stay at home?
Usually. The new roof is built under a temporary cover so the house stays dry.
What roof covering is used?
Natural slate is traditional; some councils accept other materials. We follow local guidance.