Frequently Asked Questions
Why is the post count one more than length divided by spacing?
A fence needs a post at both ends, not just at each spacing interval — a 10m fence with posts every 2.5m needs posts at 0m, 2.5m, 5m, 7.5m, and 10m, which is 5 posts for 4 sections, one more than the naive division.
How much concrete does each fence post actually need?
It depends on the post size and hole depth, but 2 bags of premix per post-hole is a commonly used planning estimate for a standard residential fence post. Adjust it here if your posts or holes are larger — deeper or wider holes for taller fences need more.
Why does board gap and joist spacing matter for decking?
The small gap between boards (for drainage and wood expansion) slightly increases how many boards fit across the deck width, and joist spacing determines how many support beams are needed underneath — too wide a spacing risks a springy or unsafe deck, so check your specific board's manufacturer-recommended maximum joist spacing.