How to Budget for Your Architecture Project
A realistic guide to costs, contingencies, and how to get the most value from your investment.
One of the first questions we're asked is: "How much will this cost?" It's completely understandable — and it's a question we take seriously. Here's an honest guide to understanding construction costs and how to budget realistically for an architectural project.
Construction Costs: A Starting Point
Residential construction costs in Hampshire currently range from approximately £2,500 to £4,500+ per square metre, depending on specification, complexity, and market conditions. A straightforward single-storey extension at standard specification sits toward the lower end; a highly specified new build with complex structural elements, bespoke joinery, and premium finishes will be significantly higher.
These figures are for construction only. They don't include:
- Professional fees (architect, structural engineer, party wall surveyor)
- Planning and building regulation fees
- VAT — typically 20% on new build, though extensions to existing dwellings are often exempt
- Fit-out — furniture, appliances, landscaping
A rough rule of thumb: allow an additional 20–25% on top of your construction budget to cover all of the above.
The Contingency
Every construction project should carry a contingency — typically 10–15% of the construction budget. This isn't pessimism; it's prudence. Unexpected groundwork conditions, changes to the brief, or fluctuations in material costs are a normal part of any project. Having a contingency means you can respond to these without stress.
Where to Spend and Where to Save
Not all spend is equal. In our experience, the areas that deliver the greatest long-term value are:
- Structure and fabric — insulation, windows, roof
- Mechanical and electrical services — heating, ventilation, electrical
- Kitchen and bathrooms — high-use spaces where quality pays dividends
Areas where specification can be adjusted without compromising the design include: floor finishes in secondary spaces, internal doors, and landscaping (which can be phased).
The Value of Good Design
A well-designed extension or renovation consistently adds more value than it costs — particularly in the Hampshire market, where demand for well-specified family homes remains strong. But beyond the financial return, the value of living in a beautifully designed home is difficult to quantify and impossible to overstate.
We're always happy to discuss budget early in the process. A clear brief and a realistic budget from day one leads to better outcomes for everyone. Get in touch to start that conversation.
