What base for artifical grass?

[KSB3155]

I'm planning on installing artificial grass on a small 3sqm plot.

There are plenty of helpful hints and instructions within the Bunnings community, but in planning for the materials quantities, I'm not sure how much to buy.

The on-line video instructions say I'll need a 60-70mm bed of crushed rock or gravel - so presumably roadbase - then 20mm of Crusher Dust.

1) What coverage will I get out of a 20kg bag of roadbase (for 60-70mm thick coverage)?

2) What coverage, (for 20mm layer) will I get out of a 20kg bag of Cracker Dust

Thank you.

[JacobZ]

Hi @KSB3155,

Welcome to the Bunnings Workshop community, it is fantastic to have you with us.

When you are working with landscaping materials, it is easiest to convert everything into cubic metres.

For a 3 square metre plot, a 60 mm roadbase layer works out to 0.18 m³, and a 70 mm layer comes to 0.21 m³. A standard 20 kg bag contains roughly 0.01 m³, so dividing your required volume by that figure gives you about 18 bags for a 60 mm layer or about 21 bags for a 70 mm layer. This also allows a little flexibility for compaction and levelling.

For the crusher dust layer at 20 mm deep, the total volume is 0.06 m³. Using the same approximate bag volume of 0.01m³, you will need about 6 bags to form a smooth, compact bedding layer for the turf.

Let me know if you have any further questions.

Jacob

[KSB3155]

Thanks Jacob.

Also, how much compaction (in height) of the roadbase and crusher dust layers could I expect?

 I'll be using a manual tamper, as the size of the area (which has a small tree that will be remaining in place) wont suit a vibrating plate.

Regards

KSB

[EricL]

Hello @KSB3155 

Since you are using a manual compactor, we can conservatively estimate that anywhere from 5mm to 10mm will get compacted depending on the uniformity of impact of the tool and how high your lifting it. The higher and stronger the lift the deeper the compaction will be. My best advice is to lift steady to keep it uniform.

Eric