1.8m (6ft) panels 1.83m wide, 100mm timber posts, one straight run, 2 bags per post.
Fence length
Panels
Posts
Postcrete (20kg)
6 m
4
5
10 bags
10 m
6
7
14 bags
15 m
8
9
18 bags
20 m
11
12
24 bags
30 m
16
17
34 bags
The sum
Panels = fence length ÷ 1.93m (panel + post), rounded up
Posts = panels + 1 per straight run
Postcrete = posts × 2 bags
The fence calculator handles corners, other panel heights and concrete posts. The fence guide shows how to set the posts so they survive the next storm.
Frequently asked questions
Is one bag of Postcrete enough for a fence post?
One 20kg bag can do for short posts in firm ground, such as a 3ft or 4ft fence. For 6ft fences, which catch a lot of wind, use two bags per post, and three in soft or sandy soil.
How deep should a fence post hole be?
About a quarter of the post's length in the ground: roughly 600mm for a 2.4m post holding a 1.8m panel, in a hole about 300mm wide.
How many posts for a fence?
One more post than panels in each straight run. A run of 6 panels needs 7 posts; a fence that turns a corner needs one extra for each extra run.
