How to use the roof replacement cost estimator
- Choose units and enter the sloped roof area (use the roofing material calculator if you only have the footprint).
- Enter material and labour prices per square or per m² from your quotes.
- Enter the number of existing layers to remove and the tear-off price per layer.
- Add disposal, permits, extras and a contingency percentage.
- Review the itemised breakdown and download it as CSV or print it.
Worked example
2,000 sq ft roof, 10% waste, example prices
With example prices of $150 per square for materials, $200 per square labour, one layer of tear-off at $50 per square, $500 disposal, $300 permits and 10% contingency: materials 22 squares × $150 = $3,300; labour 20 × $200 = $4,000; tear-off $1,000; subtotal $9,100; contingency $910; total $10,010 ($500.50 per square). These prices are placeholders, not market rates.
How it works
Imperial billing units are squares (area ÷ 100); metric uses m². Materials = units × (1 + waste) × material price. Labour = units × labour price. Tear-off = units × layers × price per layer. Subtotal = materials + labour + tear-off + disposal + permits + extras. Contingency = subtotal × contingency %. Total = subtotal + contingency.
Assumptions
- Every price (materials, labour, tear-off, disposal, permits, extras) is entered by you. The starting values are placeholders, not market prices.
- Waste applies to materials only; labour and tear-off are priced on the roof area without waste.
- Contingency percentage is your own choice.
- Switching units converts prices at 1 square = 9.2903 m².
Frequently asked questions
Is this a roofing quote?
No. It is an illustrative budget built from the prices you enter. Only a contractor who has inspected the roof can quote, because hidden damage, access and roof complexity affect the price.
Why include a contingency?
Rotten decking, extra layers or flashing repairs are often found only once the old roof is removed. A contingency keeps the budget realistic.
Where do I get prices?
Ask at least two or three local roofers for itemised written quotes, and ask suppliers for material prices for your chosen product.
Limitations
- Does not model steep-roof or height surcharges, structural repairs or financing.
- Illustrative estimate only; not a quote or a price guide.