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Roofing Cost Calculator

Roofing cost depends on roof area, material price per square meter, and waste for ridges and cuts. This calculator also supports labor cost for installation.

What Is Roofing Cost?

Roofing cost estimates the total material and labor expense for covering a roof, calculated from roof area, price per square meter, and a waste allowance for cuts, ridges, and hips. Adding labor covers installation, underlayment, and flashing.

Formula: Area x Price per area x (1 + Waste%)

Example

Formula: Area x Price per area x (1 + Waste%)
= 120 m² x 12 per m² x (1 + 10%)
= 1584.00

Enter roofing area, unit price, and waste percentage to estimate cost.

Tip: Roofing waste is often 8–15% for cuts and ridges.

Step-by-step calculation

  1. Enter roof area and unit price.
  2. Add waste percentage for cuts and ridges.
  3. Calculate the total cost.

How this is calculated

Cost = true roof area times rate per m² for the chosen covering (tiles, metal, or shingles), plus underlay and labor.

Sources: Manufacturer roof covering specifications.

FAQ

How do I calculate roofing cost by hand?
Multiply area by price per m², then by (1 + waste%). Add labor if needed.
What is the formula for roofing cost?
Cost = Area x Price per m² x (1 + Waste%). Example: 120 m² x 12 x 1.10 = 1584.
Shingles vs metal roofing cost
Shingles are cheaper per m² but need replacement sooner; metal lasts longer but costs more upfront.
What units should I use?
Use m² for roof area and per m² for material price.
Can I use this for a flat roof?
Yes. Enter flat roof area and pitch factor of 1.0.

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