Basement / Cellar Conversions in County Down (1)

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Mawhinney Maintenance And Building
10.00
(26 reviews)
Operates in Down
Services & skills
Builder
Basement / Cellar Conversions
Project Management
Fire and Flood Renovation
Agricultural Building
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Find Companies for Basement and Cellar Conversions in Down

Dreaming of converting your cellar or basement into a home office, cinema room, or guest bedroom, but unsure about who to hire and how much it will cost?

Checkatrade can help.

Keep reading for everything you need to know about basement and cellar conversions in Down and how to hire a checked and reviewed tradesperson for the job.

Want to jump straight into it? Try our quick request a quote feature and we’ll put you in touch with experienced basement conversion companies covering your local area.

Average cellar conversion costs in Down

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Looking for basement excavation prices? Our cost guide to building a basement has all the details.

Top tip: You can also try out our job estimate calculator to get a steer idea on costs for your project.

Do I need planning permission to convert a cellar?

Most cellar conversions don’t need planning permission if you’re converting an existing space.

However, if you’re excavating deeper, changing the external appearance, or creating a new entrance, you’ll likely need permission and Building Regulations approval.

Contact your local authorities as a first port of call.

Is a cellar conversion worth it?

Yes – converting a cellar can add valuable living space and increase the property value. It’s also a great option for homeowners in areas where extending upward or outward isn’t possible.

Are basements legal in the UK?

Basements and cellars are legal in the UK, but the work must comply with UK Building Regulations.

This ensures the conversion meets industry-standard requirements for damp proofing, ventilation, fire safety, and structural safety.

Can you convert a cellar into a bedroom?

Yes - with the right planning and building work, you can convert a cellar into a bedroom, guest suite, or even a self-contained studio.

To meet building regulations, your cellar bedroom will need:

Proper ventilation and insulation
A safe fire escape route
Adequate ceiling height and natural light
In some cases, planning permission

These checks aren’t just for comfort - they’re essential if you ever decide to sell your home. A compliant conversion can add value and avoid issues during surveys or legal checks.

Why use Checkatrade?

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