Home Conversion & Extension Costs in Bournemouth
Clear, Honest Pricing for Your Project
Looking for building costs in Bournemouth? At The Big Conversion Company, we provide clear and realistic pricing from the start — helping you plan your project with confidence.
Whether you’re considering a garage conversion, loft conversion, or home extension, this guide will give you a clear idea of typical costs.
Garage conversions are one of the most cost-effective ways to add space.
Typical Costs:
- Basic conversion: £8,000 – £15,000
- Mid-range finish: £15,000 – £25,000
- High-end / structural changes: £25,000+
What affects the cost?
- Insulation requirements
- Structural alterations
- Plumbing (if adding bathroom/utility)
- Windows and doors
Loft conversions vary depending on the type and structure.
Typical Costs:
- Velux loft conversion: £20,000 – £35,000
- Dormer loft conversion: £35,000 – £60,000
- Hip-to-gable / complex: £60,000+
Key cost factors:
- Roof structure
- Steelwork requirements
- Staircase installation
- Bathroom additions
Extensions are more complex and vary depending on size and finish.
Typical Costs:
- Small extension: £25,000 – £45,000
- Medium extension: £45,000 – £80,000
- Large / high-end: £80,000+
What impacts cost?
- Ground conditions
- Structural work
- Glazing (bi-folds can increase cost)
- Internal finishes
Many homeowners receive very different quotes — this is usually because:
- Some quotes exclude key elements
- Specifications are unclear
- Finishes are not defined
- Structural requirements are unknown
At The Big Conversion Company, we aim to provide detailed and transparent estimates, so you know exactly what’s included.
What’s Included in Our Estimates
We aim to include everything required for your project:
- Labour and materials
- Structural works
- Electrical and plumbing
- Plastering and finishing
- Project management
This helps avoid unexpected costs later in the build.
How to Budget for Your Project
We recommend:
- Allowing a 5–10% contingency
- Finalising designs early
- Choosing finishes before work begins
This ensures a smoother, more predictable build.
❓ Frequently Asked Questions
How accurate are these costs?
These are guide prices based on typical projects. Final costs depend on design and specifications.
Can you provide a fixed quote?
Yes — once plans and specifications are finalised, we can provide a detailed quote.
Do costs include VAT?
Prices are typically quoted + VAT, unless stated otherwise.
How do I get an exact price?
We recommend a site visit and reviewing your plans in detail.
Do I need planning permission for a conversion or extension?
Many garage and loft conversions fall under permitted development and may not require planning permission. However, larger home extensions or properties in certain areas may need approval.
For up-to-date guidance, you can visit the Planning Portal: https://www.planningportal.co.uk/
We’re also happy to advise based on your specific project and help guide you through the process.
📞 Get a Detailed Quote
If you’re planning a project and want a clear, honest estimate:
👉 Contact us today to arrange a consultation
We’re here to help you plan your project properly from the start.