Why this arithmetic matters
The claim that housing is wrecking UK public finances usually skips the cost side. Before a single square foot of land is bought, the physical build of a modest three-bed sits between roughly £220,000 and £280,000. Add land, planning obligations, professional fees and the cost of financing the whole thing for eighteen months, and the break-even price in much of the country climbs above what local buyers can pay.
When the total cost stack plus a normal developer margin exceeds the achievable sale price, schemes stall, obligations get renegotiated down, or the state ends up subsidising the gap. Move the sliders to see how thin the margin is, and how quickly a £30,000 change in land price or a two-point rise in finance costs flips a scheme from viable to unbuildable.
Presets reflect the low, mid and high ends of the quoted build range. All figures are per home and illustrative; real schemes vary by region, density and tenure mix.