DIY Shed Cost Calculator
Use our DIY shed cost calculator to estimate the cost of building a DIY shed. It'll help you decide on its size, roof type, and overhang length, and find the span of the roof rafter required.
Cost breakdown
| Element | Share | Cost | Per sq ft |
|---|---|---|---|
| Foundation and slab | 15% | 720 | 6 |
| Framing and roof | 40% | 1,920 | 16 |
| Cladding and finish | 30% | 1,440 | 12 |
| Everything else | 15% | 720 | 6 |
| Base total | 100% | 4,800 | 40 |
Shares are yours to set — regional prices, specification and how much you do yourself move them a long way.
The formula
cost = area × cost per unit area, broken down by trade
The contingency is not optional
Construction estimates made from a rate per square foot are indicative at best. Ground conditions, access, specification changes and local labour prices all move the figure, and they move it upward far more often than down.
Fifteen per cent contingency is a reasonable minimum for work you have priced carefully, and twenty-five is not excessive for a first project or anything involving existing structure. The one thing a contingency is not for is scope you already know you want.
Break the total down by trade before trusting it. If any single line looks implausible against a real quotation, the rate per square foot was wrong.