Custom Sheet Metal Is Billed by the Foot, So Ask for the Footage

Most of a St. Louis roof quote is priced by the square, which is 100 square feet of roof area. The metal work is different. Counterflashing, step flashing that has to be bent to fit a wall, pans under skylights, and cap metal at a chimney or parapet are often priced by the linear foot, or by the piece, or folded into one line with a single total. When a quote shows one number for all of that metal, you cannot tell how much of the price is material and how much is labor, and you cannot tell whether the footage it assumes matches your house.

Where custom metal shows up on a St. Louis house

Brick houses in older parts of St. Louis County and inside the city usually have step flashing and counterflashing along every place the roof meets a wall. A brick chimney, a parapet, or a dormer side wall each adds a run of metal that has to be cut and bent on site, or pre-bent from coil stock. A second story that rises above a porch roof adds another junction, and so does an addition that was built after the original roof went on. Each of these runs is a measurable length, and each one carries a cost that does not show up in the square count.

Freeze and thaw cycles add a second reason to ask. Water finds its way into any joint that the sun and the frost have worked loose, so the sealant and the reglet cut in the mortar are part of the metal line, not a free extra. A quote that names the metal but says nothing about the sealant or the reglet has left out labor that the crew still has to do.

Why the footage is the number

A unit price for custom metal is only as good as the footage behind it. If the quote says chimney flashing with a lump sum and no length, the crew may be pricing a chimney that is a different size than yours. The fix is simple. Ask for the length of each run in feet, the metal type and gauge, the finish, and the price per foot. Then multiply the footage by the unit price yourself. If the result does not match the total on the quote, ask the roofer to explain the gap before you sign.

A 25-foot tape is enough to check the main runs. Walk the house and note the wall length at the chimney base, along each dormer side, and at any sidewall where a lower roof meets a taller wall. Write the numbers on the same sheet where you wrote the square count. Then compare them with the footage on the quote. Small differences are normal, since the crew will add a lap at each joint and an extra allowance at each corner. Large differences are worth a question before anyone cuts metal.

Metal lines that often arrive as a lump sum

• Step flashing and counterflashing at brick, stone or stucco walls
• Pans and curbs around skylights, plumbing stacks and exhaust fans
• Custom cap metal at a chimney crown, a parapet or a short wall top
• Reglet cuts in brick mortar, which take labor even when the metal is inexpensive
• Inside and outside corner pieces that have to be formed by hand
• Sealant at metal laps and at the top edge of counterflashing

Each of these is a line you can ask about by name. If the quote groups them together, ask the roofer to break the group into separate lines, each with its own footage or piece count. A grouped line is not wrong in itself, but it makes it hard to see which part of the price is metal, which part is labor, and which part is the allowance for the crew to add extra length on the day.

What a fair line looks like

There is no single correct price per foot for custom metal, because the price moves with the metal type, the number of bends, and the access. A simple step flashing run on a single-story wall takes a short time to form and fit. A counterflashing that has to be cut into mortar joints on a three-story brick wall takes longer, and it often needs a ladder, a lift or a second person holding the piece. Ask each roofer to show the material and the labor on separate lines, so you can compare the metal cost directly and see where the time goes.

Compare the lines across quotes using the same footage. If one roofer prices the counterflashing at a higher per-foot rate but measures a shorter run, the two totals may be close while the work is not the same. Put both quotes on one sheet with the footage in one column and the unit price in the next, and the difference will show.

What to ask for in writing

1. The footage of each custom metal run, in feet, with the wall or junction it belongs to
2. The metal type, gauge and finish for each run
3. The unit price, and whether it is per foot or per piece
4. Whether the price includes the reglet cut, the sealant and the fasteners
5. Whether extra footage found on the roof will be priced at the same unit rate

The last item matters most. A crew that finds a longer wall than the estimate assumed should tell you before the metal is cut, and the extra length should carry the same unit price as the rest of the run. If the quote is silent on this point, ask. A written answer is better than a verbal one, because the crew member who answers your question on the ladder may not be the person who writes the final invoice.

Metal that cannot be measured from the ground

Sometimes the exact length of a wall cannot be known until the old shingles, drip edge or siding are off. In that case, a sound quote states a unit price and a stated footage, and it says the final footage will be measured on site and billed at the same rate. That is not a vague quote. It is a quote that says what is known and what is not, and it gives you the rate you need to check the final bill. Be cautious with a quote that gives one lump sum for flashing that cannot be measured from the ground, because the lump sum usually hides the footage it assumes.

Check the footage against your own house

Pull the measurement sheet from your roof visit, if the roofer gave you one, and find the wall lines on it. On a separate sheet, draw each place where the roof meets a wall, and write the length beside it. Add the lengths together and compare the total with the footage on the quote. Keep the sheet with the written scope and the photo file, so the numbers stay in one place when you ask questions or compare bids.

If the numbers do not match, you have a specific question to ask. Ask which wall the footage was taken from, whether the chimney was measured at the base or at the crown, and whether the counterflashing allowance includes the reglet depth. Those answers will tell you more about the quote than the total will.