Decks, fences & roofs
Building a deck, running a fence, shingling a roof or cutting stringers.
These are counting problems rather than area problems, and they go wrong in two specific ways. The first is the fencepost problem: a 24-foot run at 8-foot spacing has three bays but four posts, because both ends get one. Dividing the run by the spacing leaves you a post short.
The second is nominal versus actual sizing. A 4x4 post measures 3.5 inches and a 2x6 deck board is 5.5 inches wide. Roofing has its own version in the pitch factor, which makes a 6/12 roof twelve per cent larger than the footprint beneath it.
- Board foot Board feet and the cost of them, worked out on the nominal size the yard bills.
- Decking Board rows, linear feet, joists and screws for a deck.
- Fencing Posts, rails, pickets and concrete for a run of fence.
- Plywood & sheet goods How many sheets a floor, roof or wall takes, in any sheet size.
- Roofing Roof area, squares and shingle bundles, with the pitch properly accounted for.
- Stairs Risers, treads, total run and stringer length from your floor-to-floor height.