Share
Hi, we’ve recently installed a retaining wall at 400 mm in height . We need to bring the soil level up 400 mm, and lay new turf.
My question is regarding the best product to use for back fill, as there is quite a lot of backfill required. Wondering if we should use some road base first for the first 200mm then soil fill?Then prep for grass?? I don’t want the lawn to drop once it’s settled , so not sure about the road base .
Welcome to the Bunnings Workshop community @lissag. It's sensational to have you join us, and many thanks for your question about lawn fill.
How much fill will be required so the new grass finishes flush with the old? Remember, the grass itself has a thickness to it, too, around 40mm. If you require more than 100mm of soil, then you could consider adding a roadbase first. However, you typically add slightly more soil than needed, so it settles down to the correct height.
I'd suggest you add your soil and add 30mm more than what is required. Place a section of grass down and walk over it to bed it in. Water it in and then check the height. If it's level with the rest of the lawn, you can continue or adjust the amount of soil until you hit your required height. Remember, it will settle slightly over the following weeks, so it is better to lay it slightly proud of the surrounding grass.
Here's a helpful guide: How to lay turf.
Please let me know if you have any questions.
Mitchell
Sorry @lissag. I presumed you were filling the ground in front of the retaining wall and repairing the grass there. If this is for behind the retaining wall, then you could definitely fill with roadbase for the first 200mm.
I'll point out that the palm and other plants are planted in the ground, and raising the soil 400mm up their trunks could quite possibly kill them. Also, you don't appear to have continued the retaining wall into the back corner and along the fence. You'll need a retaining wall there to prevent the fence from becoming the retaining wall; fences are not designed to retain soil.
Mitchell
