How to Reduce Home Extension Costs: How Smarter Spatial Design Saved One Client £31,000

We help Maximise Your Rental Income with Eco-homes and Luxury Holiday Homes, provided by RIBA Chartered Architects.

In one recent project, we saved a client just over £31,000 in construction costs. This was done by rethinking how the space was arranged.

When the client first approached us, they had already sketched out a design for their home extension. On the surface, it made sense: they wanted more space, and the extension delivered exactly that. But once we started working with them through it, a few issues became clear.

The proposed layout created a much larger corridor than was really necessary, awkward wall junctions, and additional rooms that didn’t have a clear purpose. In practice, those rooms would have gone largely unused, becoming wasted space that still had to be built, heated, finished, and maintained.

By reworking the spatial arrangement, we were able to reduce unnecessary circulation, simplify the layout, and design rooms that genuinely earned their place in the house. The result was a home that worked far better for the client’s day-to-day life, while significantly reducing build costs.

One of the many changes was designing the spare bedroom to work harder. When not in use by guests, it now functions as a proper home office, a space that’s used daily rather than occasionally. No extra square metres were added, but the usefulness of the house increased dramatically.

Quality of Space Over Quantity

All too often, designs look impressive on paper because there’s simply more space. Larger rooms may sound good on paper, but in reality, it adds very little to day-to-day usage. Moreover, in some instances, additional space can, in fact, compromise the quality of the remaining space around the home, as the additional space can darken rooms in the house.

Every unnecessary square metre still carries a cost. Foundations, structure, finishes, services, it all adds up. Good spatial design isn’t about squeezing a house smaller; it’s about making sure every part of it has a clear purpose.

If you’re considering extending your home and want a more considered approach to spatial arrangement, one that focuses on livability, flexibility, and cost control, you can use the link below to schedule a free call with me to talk it through with myself.