Calculadora de Custo de Construção Online Grátis
Project cost estimate with area, labor rate, material cost and contingency
The Construction Cost Calculator produces a parametric project budget by combining floor area, labour rate per square foot or metre, material cost estimates, and a contingency percentage into a structured cost breakdown. Project managers, property developers, and homeowners planning extensions or renovations use it to stress-test budgets before committing to contracts.
Frequently Asked Questions
Sobre Esta Calculadora
Construction budgets routinely overrun because early estimates include only the headline build cost and omit the contingency, professional fees, planning costs, utility connections, and site preparation that together typically add 25–40% to the base construction figure. This calculator makes those line items explicit rather than letting them surface as surprises.
The cost-per-area approach is a starting point, not a final quotation. Regional labour costs, site conditions, material specifications, and structural requirements all drive significant variation. The UK average new-build cost differs substantially from London rates; a timber-frame extension costs differently from masonry. Enter costs from real quotes into the individual fields for a more accurate picture.
The built-in chart breaks the total into material, labour, professional fees, and contingency categories, making it easy to show clients or stakeholders where the budget goes. For comparison analysis, vary the contingency percentage (5% for straightforward projects, 20% for complex conversions) to see the sensitivity of the total to that single assumption.
A Calculadora de Custo de Construção produz um orçamento de projeto combinando área, mão de obra e materiais.
Exemplo Resolvido
Estimating cost for a 50 m² single-storey extension
Entradas:
- Floor area: 50 m²
- Build cost rate: £1,800/m²
- Contingency: 15%
- Professional fees (architect, engineer): 12% of build cost
Passo a Passo:
- Base build cost: 50 m² × £1,800 = £90,000
- Contingency (15%): £90,000 × 0.15 = £13,500
- Professional fees (12%): £90,000 × 0.12 = £10,800
- Total project cost: £90,000 + £13,500 + £10,800 = £114,300
- Cost per m² including all extras: £114,300 ÷ 50 = £2,286/m²
Dicas
- Always add 10-20% contingency to construction budgets for unexpected costs.