How Much Does It Cost to Build a House or Extension?

By Roger Hines – Habitat Architecture Updated for 2025

We’ve all had that moment—wondering, Can I afford to build my dream home? or How much will it cost to extend my current home?

This is one of the most common questions we get from clients. Now, before we dive in, it’s worth noting that we’re not Quantity Surveyors (and they’d likely wince at our approach—believe me, I’m married to one!). However, we do keep a close eye on construction costs by speaking with local trades and tracking industry trends.

How Do We Estimate Costs for a Project?

We gather data from multiple sources, including industry reports, online resources, and direct conversations with builders and suppliers. This helps us stay informed on how market conditions and material prices impact the overall cost of building or extending a home.

Building or extending a home is an exciting and rewarding experience, but it can also be overwhelming, especially in the early stages. Common questions include:

• Where do I start?

• How much will this cost?

• Do I need a builder or an architectural designer first?

To help, we’ve put together this cost guide based on current trends in the North West of England. These figures provide a rough estimate, but every project is unique, and final costs will depend on various factors.

Construction Costs per Square Meter (m²) – 2025 Guide

The following table provides an outline of average build costs based on different quality levels. These prices are exclusive of VAT, though new-build homes are typically zero-rated for VAT.

Cost Level	Low	Average	High
Construction cost per m²	£2,000	£2,500	£3,200
2-bed house (95m²)	£190,000	£237,500	£304,000
3-bed house (120m²)	£240,000	£300,000	£384,000
4-bed house (150m²)	£300,000	£375,000	£480,000

These costs are for the build alone and don’t include:

• Planning & Building Regulation Fees – Statutory fees for approvals

• Professional Fees – Architectural, structural, and consultant fees

• Service Connections – Gas, water, electric, and drainage

• Legal Fees – Land purchases, contracts, and other legal requirements

If you’re planning a new build on a challenging site (such as a sloped plot, a greenfield location, or a conservation area), you may also need additional specialists, such as ecological consultants or flood risk assessors.

For Context.... This is a single-storey 4-bedroom home with attached 1-bedroom Annex, coming in at 315m2.

What’s Next?

If you’re considering a new build or an extension, getting the right advice early on can save you time, stress, and unexpected costs. At Habitat Architecture, we help guide clients through the process from initial ideas to final construction.

Interested in discussing your project? Get in touch—we’d love to help you design a home that fits your needs, your budget, and your lifestyle.

Contact us today to get started!

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