🏗️ How Your Home Extension Design Can Affect Cost in 2025
Designing a home extension is exciting — new space, new layout, more light, more freedom. But the truth is, your design choices have a direct and often dramatic impact on what the build will actually cost. In the UK construction climate of 2025, where labour shortages and fluctuating material prices still bite, design efficiency equals money saved . You can draw a beautiful plan, but if it’s technically complex or structurally wasteful, you’ll spend thousands more before you even break ground. This post breaks down exactly how your design affects cost — and how to keep control from the first sketch to the final build. 1. Layout and Shape — The Foundation of Cost The layout is your single biggest price factor. Simple shapes like rectangles or L-plans are cost-efficient, while irregular designs — curves, multiple corners, or offset rooms — cost far more. Each time your wall line changes direction, you add work: more foundations, more steel, more time. A 30 m² extension that’s a ...