🏠 How Much Does an Extension Cost in Scotland? Your 2025 Home Extension Guide

Thinking of adding more space to your home but not sure where to start? One of the most common questions we get is: "How much does a home extension cost?" Whether you’re planning a kitchen extension, loft conversion, or full two-storey build, understanding the costs is key to a successful project.

In this guide, we’ll break down the latest home extension costs in Scotland and explore what factors can affect your budget.

💷 How Much Does a Home Extension Cost?

The cost of a home extension in Scotland depends on a range of factors including the type of extension, materials, design complexity, and location. Here's a rough guide for 2025:

📏 Single-Storey Extension Cost

• £1,800–£2,500 per m²

• A 20m² extension may cost between £36,000 and £50,000

🏗️ Two-Storey Extension Cost

• Slightly more expensive due to extra structural work

• Offers more space for your spend (e.g. adding a bedroom and bathroom)

🧱 Side Return Extension

• Typically £2,800–£3,800 per m²

• Often used in terraced homes to expand kitchen/living space

🌿 Conservatory Extension

• From £1,800 per m² for basic uPVC models

• Ideal for adding light-filled rooms with a garden connection

➡️ In cities like Edinburgh, prices can rise to £3,000 per m², while Glasgow tends to range between £1,600 and £2,500 per m²

🧾 Other Costs to Factor In

When planning how much a home extension costs, don’t forget about these additional expenses:

• VAT: 20% on labour and materials

• Structural Engineer: £1,000 +

• Planning Application Fee (in Scotland): from £300 for extensions and more depending on project size

• Building Warrant: Required for most extensions – budget around £150–£500

• Party Wall Agreements (if needed): £700–£1,000 per affected neighbour

• Contingency Fund: Always set aside 10–12.5% for unexpected costs

🛠️ What Affects the Cost of a Home Extension?

Several factors can influence how much your home extension will cost:

• Location: Urban areas like Edinburgh may have higher labour and material costs

• Design Complexity: Bespoke or modern designs often cost more to build

• Construction Method: Traditional builds vs prefabricated methods

• Site Access: Narrow lanes or built-up areas can drive up labour and delivery costs

🔍 How to Keep Your Home Extension Cost-Effective

• Work with a local architect like Spirit + Structure Architecture who understands planning policy in your area and has years of experience.

• Get detailed quotes from multiple builders — not just estimates

• Prioritise needs over extras — smart layout decisions can reduce size and save costs

• Plan ahead — rushed planning can lead to costly mistakes down the line

🏡 Is a Home Extension Worth the Investment?

Yes — a well-planned home extension can significantly increase your property’s value and enhance how you use your space. Whether it’s an open-plan kitchen diner or an extra bedroom, an extension can transform your home without the hassle of moving.

✅ Final Thoughts: How Much Does an Extension Cost in 2025?

While extension costs vary, having a clear budget and understanding of your goals makes all the difference. In 2025, the average home extension cost in Scotland ranges between £1,800 and £3,000 per square metre — so a 30m² build could cost £54,000 to £90,000 (plus VAT and fees).

Ready to Start Your Home Extension?

If you're thinking about extending your home, get in touch for advice tailored to your project. We help homeowners across Scotland turn ideas into beautifully built spaces that fit their lifestyle and budget.