What is a basement conversion?
A basement conversion turns an existing cellar into living space, or excavates a new basement under the house or garden. Waterproofing, structural support and daylight are the main design challenges.
How much does a basement conversion cost in Airdrie?
In Airdrie, a basement conversion typically costs £1,850–£3,100 per m² for converting an existing cellar, including VAT at 20% (standard rate). For a typical 30 m² project that is roughly £55,500–£93,000. Building costs in Scotland are close to the UK average, so the figures for Airdrie are close to our national guide. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (21 m²) | £39,000–£65,000 |
| Typical project (30 m²) | £55,500–£93,000 |
| Larger project (42 m²) | £77,500–£130,000 |
| Rate per m² | £1,850–£3,100 |
Your quote will depend mainly on:
- Waterproofing system
- Floor lowering and underpinning
- Lightwells
- Existing cellar or new excavation
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a basement conversion in Airdrie?
The approval route for Airdrie is set by planning law in Scotland. In Scotland converting an existing cellar may not need planning permission, but a building warrant is needed, and new excavation usually needs planning permission.
Scotland has no Party Wall Act. Work on shared walls is governed by your title deeds, the Tenements (Scotland) Act 2004 for flats, and common law, so we agree arrangements with neighbours in writing before work starts.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
From survey to sign-off, the job normally involves:
- Waterproofing design (tanking or cavity drain membrane)
- Electrics, heating and plastering
- Lightwells and windows
- Insulation, ventilation and drainage pumps
- Underpinning or new structure where needed
- Written agreement with neighbours on shared walls
How long does it take?
The build itself usually takes 8 to 16 weeks for a cellar conversion; longer for new excavation. Allow time beforehand for drawings and approvals, usually 3 to 5 months.
Building in Airdrie
Scotland’s housing ranges from sandstone tenements and villas to post-war and modern estates, and the building warrant system shapes how projects are planned.
We work across Airdrie and neighbouring areas such as Coatbridge, Bellshill and Motherwell. Postcodes we cover in Airdrie include ML6.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about basement conversions in Airdrie
Do you build basement conversions in Airdrie?
Yes. We build basement conversions across Airdrie, including postcodes ML6. Every project starts with a free home visit.
How much does a basement conversion cost in Airdrie?
In Airdrie, a basement conversion typically costs £1,850–£3,100 per m² for converting an existing cellar, including VAT at 20% (standard rate). A typical 30 m² project comes to roughly £55,500–£93,000. Your fixed price depends on the survey and drawings.
How long does it take?
A cellar conversion takes around 8 to 16 weeks; new basements take longer.
Do I need planning permission for a basement conversion in Airdrie?
In Scotland converting an existing cellar may not need planning permission, but a building warrant is needed, and new excavation usually needs planning permission.
How do you keep a basement dry?
With a waterproofing system designed to BS 8102, typically a cavity drain membrane with a sump pump, or a tanking system.
Is new excavation worth it?
It can be in high-value areas, but costs are high. We give a feasibility view before design starts.