Roof Replacement Cost Calculator

What will a whole new roof set you back? The average roof replacement cost is about $10,000 according to Fixr, and most jobs land between $7,500 and $14,000, and This Old House puts it at $9,476 for a 2,000 sq ft home using RSMeans data. Your own number depends on three things the calculator asks for: how much roof there is, what goes on it and how steep it is.

Roof replacement cost for a typical house

This Old House priced the same 2,000 sq ft house two ways. As a one-story home it needed about 2,469 sq ft of roofing, and as a two-story home about 1,273 sq ft, because the upper floor sits on the lower one and the roof covers half the footprint. Fewer squares mean a smaller bill, even though a second story makes the work harder.

Roofers count in “squares” of 100 sq ft. A recent inspection report or the invoice from your last roof will show the number; multiply it by 100 and enter that as the roof area. The floor area of the house is not the same thing, since slope and eaves add surface.

Picking a material

The material changes the new roof cost more than anything else. Asphalt shingle roofs are the cheapest, at $3.50 to $6.50 per square foot installed for 3-tab or architectural shingles, which is why the calculator starts there. Wood shake and flat membranes sit in the middle. Tile, metal and slate cost two to four times as much: standing seam metal runs $9 to $24.50 per square foot, so the metal roof replacement cost for a 2,000 sq ft roof is $18,000 to $49,000 before removal and permits.

The full roofing cost per square foot for each material is in the table at the bottom of the page, with the sources listed under it. RoofingCalculator.com’s figure for standing seam ($18 to $24.50) is about twice the low end of the other sources, which is why the range is so wide.

Pitch, tear-off and decking

How steep the roof is

RoofingCalc adds 5 to 10% for pitches between 4/12 and 8/12 and 15 to 25% above 8/12, and our estimate takes the middle of each band. We found no figure we could verify for 10/12 and steeper roofs, so expect quotes above the “steep” estimate there.

Removing the old roof

Tearing off one layer of asphalt shingles costs about $0.50 to $1.50 per sq ft. Heavier roofs cost more to strip, $1.21 to $1.63 per sq ft for slate and $1.45 to $1.97 for tile in RoofingCalculator.com’s figures, and RoofingCalc adds $1 to $2 per sq ft when there are two or more old layers. That tear-off is part of the cost to replace roof shingles that a quick per-square price can hide.

Decking under the shingles

Rotten plywood only shows once the old roof is off. Fixr quotes $2 to $8 per sq ft for new decking and RoofingCalc $2 to $4 for spot repairs. The amount varies too much from house to house to put into an estimate, so the calculator leaves it out.

The permit is usually $100 to $500, rising to $150 to $700 in seismic, wildfire or hurricane zones according to RoofingCalc.

Reading a roofing quote line by line

A complete written quote should name:

• the material and its product line
• the number of squares
• how many layers will be torn off
• a price per sheet for any decking replaced
• who pulls the permit

When one quote is far below the others, check which of these lines is missing from it.

Roofing cost per square foot by material