ᐅ Gravel Calculation – Is the Result Correct?

Hello,

I want to order gravel (grain size 2-5mm) and am trying to calculate the correct amount. The gravel will be used as a base for lawn edging stones (24cm (9.5 inches) long, 12cm (4.7 inches) wide). I plan to install the lawn edging stones along a total length of 40 meters (131 feet). 40 meters equals 4000 cm (157 inches).

Assuming I want the gravel layer to be 5cm (2 inches) deep/high everywhere, then according to my calculation:

4000 cm (total length of lawn edging stones) x 5cm (gravel layer depth) x 12cm (width of the stones and therefore the gravel layer). This results in 240,000 cm³ (14.6 cubic feet) = 2.4 m³ (85 cubic feet).

At the hardware store, there is gravel available with a weight of 1,000 kg (bulk density 1,500). How can I determine how many kilograms of gravel I actually need, and have I calculated this correctly? Math was never really my strength...

Well, you need to multiply your volume by the ratio of bulk density to weight (in this case 1.5). That will give you the mass that fills your desired volume. Be careful, as compacting will reduce the volume again. I believe for gravel, you then add another 6%.

MaxMustaman92 schrieb:

Hello,

I want to order gravel (grain size 2-5mm) and am trying to calculate the correct amount. The gravel will be used as a base for lawn edging stones (24cm long, 12cm wide). I plan to install a total length of 40 meters (131 feet) with these lawn edging stones. 40 meters equals 4000 cm (15748 inches).

Assuming I want the gravel layer to be 5cm (2 inches) deep/ high everywhere, then according to my calculation:

4000 cm (total length of lawn edging stones) x 5cm (gravel layer) x 12cm (width of the stones and thus also the gravel layer). The result would be 240,000 cm³ = 2.400 m³ (84.8 cubic feet).

At the home improvement store, there is gravel available in 1,000 kg (bulk density 1,500) bags. How do I know how many kilograms of gravel I actually need, and have I calculated this correctly? Math was never really my strength..

Try calculating 40m x 0.12m x 0.05m = 0.24 m³ (8.5 cubic feet).
Online you can find approximate values for the specific weight of gravel—it varies somewhat, but let's assume about 1.8 t/m³ (112 lb/ft³).

Then that would be approximately 432 kg (952 pounds). 🙂

Edit after reading @Tolentino’s post: 457.92 kg (1009 pounds).

Kiesdirekt offers a calculator for this, including specific weight and compaction for many types.

I would also recommend going directly to the gravel plant rather than a hardware store. You can still fit 0.4 tons (400 kilograms) on a standard trailer.