About this calculator
Estimates the take-off for a round or squared log wall: course count from wall height and the effective per-course height, logs from stock length, and inter-log seal (chinking or gasket tape) length.
Formula
effective course height = log height − groove overlap
course count = ceil(wall height / effective course height)
logs per course = ceil(wall length / stock length)
logs (excl. waste) = course count × logs per course
logs (incl. waste) = ceil(logs × (1 + waste% / 100))
seal length = course count × wall length
sealant mass = seal length (m) × consumption (kg/m)
Openings are validated for geometric sanity (a sill plus opening height cannot exceed the wall height) but do not reduce log or sealant quantities: unlike a masonry or frame wall's unit count, logs run the full wall length and are notched for doors and windows on site — the material isn't actually saved by a small opening.
Worked example
Defaults: 6 m × 2.5 m wall, 200 mm log height, 20 mm groove overlap, 3 m stock length, 10% waste, 0.15 kg/m sealant consumption.
effective course height = 200 − 20 = 180 mm
course count = ceil(2500 / 180) = 14
logs per course = ceil(6000 / 3000) = 2
logs excl. waste = 14 × 2 = 28; incl. waste = ceil(28 × 1.10) = 31
seal length = 14 × 6 m = 84 m
sealant mass = 84 × 0.15 kg/m = 12.6 kg
FAQ
Why don't openings reduce the log count? A log wall's logs span the full wall length and are notched for a door or window opening on site — the wood isn't saved the way a masonry unit or a stud is, so deducting openings from the log count would overstate the savings.
What is "groove overlap"? The interlocking groove or tongue that each log's underside cuts into the log below reduces the net height each course adds to the wall — it's a manufacturer-specific dimension, so it's a user input here rather than a fixed constant.
Why doesn't the calculator cite a standard?
No standard was found with sufficient confidence covering log wall course, log-count, or
sealant quantity take-off, so meta.standards is left empty.
Assumptions and limits
Course count and log count are estimated from wall height, log height, groove overlap, and stock length — real log construction may waste more or less depending on corner joinery (saddle-notch, dovetail) not modelled here. Groove overlap and sealant consumption are disclosed estimates you can adjust to match your own log profile and product.