House Extension Cost Guide for Yorkshire (2025)

House extension costs in Yorkshire depend on several factors: the size of the extension, the specification of finishes, ground conditions, and the accessibility of the site. As a rough guide, budget from £1,800–£2,500 per square metre for a well-specified single-storey extension, inclusive of foundations, structure, roofing, external walls, windows and doors, first and second fix services, and standard internal finishes.

For a 20m² kitchen extension in West Yorkshire, this equates to approximately £36,000–£50,000. Higher-specification finishes — bifold doors, underfloor heating, premium kitchen — will increase costs towards the upper end or beyond. VAT is chargeable on most new build work but may be reduced or zero-rated in certain circumstances.

Architect and planning fees typically add 10–15% to the overall project cost, but bring significant value — a well-designed extension adds more to your property's value than the cost of building it. At TYA Builds, we include all design, planning, and project management within our quoted price.