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Siding

What it's for

Takes off siding for a wall and, if there is one, the gable over it. For vinyl and board and batten you get square feet to order. For fiber cement and clapboard you get lineal feet of board, the course count and the exposure. Corner trim, house wrap, starter and J-channel or opening trim are counted, and the wall is drawn with its openings. It is an order takeoff. It makes no code check.

Step by step

The example is the screen as it opens: vinyl on a wall 20' 0" long and 9' 0" high, one door, four windows, four outside corners, 10% waste.

Siding inputs at their defaults: MATERIAL Vinyl, WALL LENGTH 20' 0", WALL HEIGHT 9' 0", INCLUDE GABLE off, DOORS 1, WINDOWS 4, OUTSIDE CORNERS 4, INSIDE CORNERS 0 and WASTE FACTOR 10%. The answer bar reads 109 sq ft — order over Gross 180 · Net 99 sq ft. RESULTS repeats Gross 180 · Net 99 sq ft, with the BASIS & WHAT WAS ASSUMED row and the link Check before you cut · Measure twice. 1 2 3 4 5 6
Steps 1 to 6. With Fiber Cement or Clapboard an EXPOSURE row appears under MATERIAL.
  1. Pick MATERIAL: Vinyl, Fiber Cement, Clapboard or Board & Batten. Fiber Cement and Clapboard are figured in courses, so an EXPOSURE row appears for them: how much of each board shows once the next one laps it. Fiber cement takes the plank that shows your exposure with a 1-1/4" lap (IRC R703.10.2): 7" is an 8-1/4" plank, up to 10-3/4" on a 12" plank. Past 10-3/4" the screen asks for less. Clapboard is a 1/2x6 or 1/2x8 board, 6" at most. Vinyl and Board & Batten are figured by area and have no exposure row.
  2. Enter WALL LENGTH and WALL HEIGHT, from the bottom of the first course to the top of the wall. The screen takes one wall. For a whole house at one height, enter the total run of wall.
  3. Turn on INCLUDE GABLE to add one gable triangle. Two rows appear: GABLE BASE, across the bottom of the triangle, and GABLE PEAK HEIGHT, measured plumb from that base line to the peak.
  4. Set DOORS and WINDOWS. Each takes a fixed allowance off the area. The screen does not ask for opening sizes.
  5. Set OUTSIDE CORNERS and INSIDE CORNERS. Each corner buys one piece of corner trim.
  6. Set WASTE FACTOR. It is added to the siding and to the corner trim count.

Reading the results

Siding results: the answer bar keeps 109 sq ft — order and Gross 180 · Net 99 sq ft. RESULTS reads Gross 180 · Net 99 sq ft, then the BASIS & WHAT WAS ASSUMED row and the link Check before you cut · Measure twice. The drawing shows a 20' 0" by 9' 0" wall with a door and two windows, and the notes 180 SF GROSS − 1DR@21 − 4WIN@15 = 99 SF NET; ≈ 109 SF ORDER · 5 CNR · 10% WASTE; VINYL — ENGINE COMPUTES NO COURSING; OPENINGS 3 OF 5 · ASSUMED 3-0×7-0 DR, 5-0×3-0 WIN, over the title strip SIDING WALL, VINYL PANELS, NOT TO SCALE. MATERIALS starts with Vinyl 109 sq ft, Outside corner trim — 1 per corner, 9' 0" long — stock at least that, 5 pcs, and House wrap (WRB) — 9' × 150' — every exterior wall (IRC R703.2); 180 sq ft gross, 6" laps, 1 roll. 7 8 10 11 12
The numbers match the list below.
  1. The headline is what to order, waste included. For Vinyl and Board & Batten it is square feet; on the defaults, 109 sq ft — order (99 × 1.10 is 108.9, rounded up to the 109 the material list buys — the headline and the list are the same number). For Fiber Cement and Clapboard it is lineal feet of board, rounded up the same way.
  2. Gross and net. Gross is wall plus gable. Net is gross less the door and window allowances. On the defaults: Gross 180 · Net 99 sq ft. With a gable on, its area is added to the line.
  3. Courses and exposure show for Fiber Cement and Clapboard only: the course count, the board size the exposure calls for, the exposure actually used, and the lineal feet of boards. If the exposure shown is smaller than the one you entered (clapboard over 6"), the calculator has held it to the most that board size can show, and a line says so: Exposure 7" typed — counted at the 6" most a 1/2x8 shows with a 1-1/4" lap. For those two materials a BASIS & WHAT WAS ASSUMED row also appears. Tap it to read how the boards were counted: courses at the wall's height times its length, the gable added and the door and window allowances taken off, each at its area divided by the exposure — so the lineal feet follow the net area shown above them.
  4. The drawing is an elevation of the wall with its openings. Pinch to zoom, drag to pan, double-tap to reset, and use the expand button for full screen. See Drawings.
  5. The notes under the drawing are where you check what was assumed. The first line is the area sum with the allowance for each opening, here 1DR@21 − 4WIN@15, and the last line gives the opening sizes those allowances stand for. It also tells you when not every opening fits on the picture, here OPENINGS 3 OF 5. All five are still deducted.
  6. MATERIALS lists the siding in its order unit and the corner trim in pieces. Four outside corners at 10% waste come to 5 pcs on the defaults. Then what the siding hangs on: House wrap (WRB) in 9' × 150' rolls over the whole wall and gable, openings included — IRC R703.2 puts a water-resistive barrier behind every exterior wall's siding — figured at 1,275 sq ft a roll after 6" laps; Starter strip in 12' pieces along every wall base (not for board & batten); for vinyl, J-channel in 12' 6" sticks around each door (17'), each window (16') and up the gable rakes; for fiber cement and clapboard, Opening trim in lineal feet over the same opening runs; for board & batten, Battens at 12" o.c. Nails are not counted: their size and spacing come from the siding maker, and BASIS & WHAT WAS ASSUMED says so.

There are no red flags on this screen. Nothing here is a pass or a fail.

Siding is a Pro calculator. SHARE PDF and SAVE are Pro as well, a one-time purchase. SHARE PDF and the list icon at its right end stay dim until you have entered your own measurements. SAVE stays lit, but until then a tap only answers Enter your job's numbers first and saves nothing.

Common mistakes