Measure walls, subtract openings, count the extras

Measure each wall's length and height for gross square footage, then subtract windows and doors. Gable ends are triangles — half the base times the height. Add the areas up and apply a waste allowance that fits the material and the house: more cuts and corners mean more waste. Siding is sold in squares (one square covers 100 square feet) or by the piece depending on the material, so convert your area to the unit your supplier uses.

While you measure, count the detail work separately: outside and inside corners, J-channel and trim around every opening, fascia, soffit, and frieze boards. On most houses the trim package is a significant share of material cost, and it is the part a square-foot guess always misses.

Decide what happens under the old siding

Full tear-off or reside over the top is a scope decision with real consequences. Tear-off adds labor, disposal, and a dumpster, but it lets you inspect the sheathing, install new wrap properly, and guarantee your own work. State the choice plainly on the estimate — customers regularly compare a tear-off quote against a reside-over quote without noticing the difference.

Old siding hides things: rotted sheathing, missing flashing, insect damage. You cannot price what you cannot see, so write an assumption line — sheathing repair billed at a stated sheet rate or hourly basis, approved by the customer as it is found. That single line turns the worst surprise in the trade into routine paperwork.

Build the material list in layers

Price each layer from your supplier's current numbers. Material prices move, and a quote built on last year's numbers is a donation. How to price materials covers keeping material lines honest.

  • Field siding: area in your supplier's unit, plus waste
  • Tear-off and disposal: labor hours, dumpster, dump fees
  • Weather barrier: house wrap, flashing tape, and the window/door flashing details
  • Trim package: corners, J-channel, starter, undersill, fascia, soffit
  • Fasteners and caulk — small money that adds up across a house
  • Scaffolding or pump jacks for anything above comfortable ladder work

Price labor from production, not hope

Siding crews work in squares per day, and your rate is yours: track how fast your crew installs each material — vinyl, fiber cement, and wood are different speeds — on straightforward walls versus cut-up ones. Fiber cement in particular is heavier, slower, and harder on blades and bodies; if you have only installed vinyl, do not borrow your vinyl rate.

Height, landscaping, and access stretch the clock, and so do the details customers love: shakes in the gables, board-and-batten accents, wrapped windows. Price the detail work as its own line when it is significant — it is real hours, and showing it justifies the number.

What the customer should see

The estimate should name the exact product and color line being installed, the scope (tear-off or reside-over), wrap and flashing details, trim work, disposal, and the assumption clause for hidden damage. A line for lead-safe practices may apply on pre-1978 homes — check your local requirements and say how you handle it.

Siding quotes are compared line by line against two or three competitors, so clarity wins. EstimateBook can draft the itemized estimate from your voice notes at the site; you verify the measurements and prices, then send the PDF before you leave. The draft is a starting point — the measuring tape is the authority.