Once your area is clearly outlined, mark a grid-layout and evenly lay your plastic post network. Space the posts at 1,500mm intervals in residential settings and 1,000mm in commercial settings. This is in keeping with the maximum support span of the large plastic joist that will be used to form your cross-bearer and joist network.
Fix the posts to your base by forming a hole and cementing them into the ground. A third of the length of the post (or at least 500mm) should be secured under the surface of your base. Ensure the posts remain in an upright position as the concrete sets and that the tops of the posts are level with one another.