Drywall Layout Calculator

Each wall is laid out the way a hanger lays it: courses from the top down, sheets from one end, the last piece cut to fit, openings hung over and cut out afterwards. What makes a layout good or bad is where the end joints land, and the Gypsum Association's rules say where they may not: within 12" of the corner of a door or window, where cracks start; off the framing; or lined up with the joint in the course above. For every course the calculator tries each starting length that puts the joints on studs, throws out any that break a rule, and keeps the one with the fewest pieces and no slivers. If no start clears every rule, it says which joint it could not move and why.

Sheets are counted from the pieces, not from the area: a full-length piece is a sheet, a shorter one comes out of the longest offcut that will take it or out of a new sheet, and a ripped course draws on its own offcuts. When the sheet length is left open, each wall gets the length that lays out cleanest with the fewest sheets. In the example on this page, a 168" wall with a window takes 3 sheets of 12', and the whole room comes to 15.

Compound, tape and screws are figured on the finished area, openings taken out, at a retailer's estimating rates for a three-coat finish with paper tape, and rounded up to buckets and rolls.

1. Enter each wall's length and height, and its doors and windows: how far from the left end, how wide and tall, and how high the sill is (zero for a door).
2. Add the ceiling if you are doing it, and say which way the joists run.
3. Set the stud spacing and the sheet size. Leaving the length open lets each wall take the size that lays out best; fix it if the yard or the stairs only allow one.
4. Read the count and the consumables, and print the hanging plans. Each shows every piece with its size, the end joints, and anything the layout could not clear.