How Much Does a Home Extension Cost in Kent? 2025 Price Guide

Planning a home extension in Kent? Understanding the costs involved is crucial for budgeting your project effectively. In this comprehensive guide, we'll break down the typical costs for different types of extensions in 2025.

Average Extension Costs in Kent

Extension costs in Kent vary depending on several factors, but here are the typical price ranges per square metre:

Single Story Extension: £1,500 - £2,500 per m²
Double Story Extension: £1,800 - £3,000 per m²
Loft Conversion: £1,200 - £2,000 per m²
Garage Conversion: £1,000 - £1,500 per m²

Factors Affecting Extension Costs

1. Size and Complexity

The larger and more complex your extension, the higher the cost. Simple rectangular extensions are typically less expensive than those with unusual shapes or multiple levels.

2. Materials and Finishes

Your choice of materials significantly impacts costs. Premium materials like natural stone, high-end windows, and quality roofing will increase the overall budget.

3. Location in Kent

Costs can vary across Kent. Areas like Royal Tunbridge Wells and Sevenoaks may have slightly higher costs due to property values and accessibility.

4. Planning and Building Regulations

If your extension requires planning permission and building control approval, factor in these costs (typically £500-£1,500).

Hidden Costs to Consider

Architect or designer fees (8-15% of build cost)
Structural engineer fees (£500-£2,000)
Party wall agreements (if applicable)
Temporary accommodation (if required)
Landscaping and driveway repairs

Example Projects and Costs

Small Kitchen Extension (15m²)

A simple single-story kitchen extension in Ashford might cost £22,500-£37,500.

Medium Family Room Extension (30m²)

A mid-range single-story extension in Canterbury could cost £45,000-£75,000.

Two-Story Extension (50m²)

A substantial double-story extension in Maidstone might range from £90,000-£150,000.

How to Keep Costs Under Control

Get multiple detailed quotes from reputable builders
Plan thoroughly before starting work
Choose cost-effective materials without compromising quality
Avoid making changes once construction has started
Consider doing some non-structural work yourself

Return on Investment

While extensions require significant investment, they typically add 15-20% to your property value, often exceeding the build cost in desirable Kent locations.

Get an Accurate Quote

Every extension project is unique, so it's essential to get a detailed, itemized quote from an experienced builder. At Built by Pros, we provide transparent pricing with no hidden costs.