Sharp & Kiln Dried Sand for Block Paving: How much you need?

Block paving is one of the most popular options for driveways. If you’re a DIYer there’re many calculations you’ve to work on throughout the job. Two such calculations are to find out here how much sharp and kiln-dried sand is going to require to complete the job.

Don’t get confused between sharp sand and kiln-dried sand because I combined them here in the post. These are the two different types of sand used for different purposes. Sharp sand is used only once as a part of the base for the block paving on which the pavers are laid.

Whereas, after laying pavers kiln dried sand is used between the paver joints to interlock them and keep them in place. Sharp sand is required only at the time of laying pavers and you’ll kiln dried sand after every few years to re-sand the block paving.

Calculate Sharp Sand Required Under Block Paving

How much sharp sand others required for their job could be different from how much you require because of things like the depth of sharp sand and how much you compact it. Some installers are fine with a 30mm compacted layer of sharp sand while some go way above 50mm. But 50mm is the common depth for the sand under the pavers.

At 50mm above the sub-base, 1 bulk bag of sharp covers around 10m2 area is ready for laying block paving. Also, there’s a standard formula Area x Depth x 2 to calculate how much sharp sand is needed for the block paving sub-base. So for example, at 50mm for 50m2 block paving, you’ll need 50 x 0.05 (50mm) x 2 = 5 bulk bags of sharp sand.

You may require more sharp sand to install block paving edges and if there needs to be linear drainage installed to collect water from the block paving.

An alternative to the sharp sand, grano dust is also being used for the laying course which has its own advantages. This is what you’ll get to know from the DIY start-to-finish block paving cheat sheet here, like how to take a little different approach to block paving as DIYers to give it a better chance of success and longevity.

Calculate Kiln Dried Sand Required Between Block Paving

After installing the pavers, the next part is to brush kiln-dried sand in the joints in dry conditions. Also, after pressure washing the existing block paving, there needs some re-sanding done to ensure the pavers won’t move from the place.

Typically, kiln-dried sand is available in 20-25kg bags. One bag should cover 8-10m2 of block paving to fill in the joints (50mm). For example, to complete sanding 50m2 of new block paving with no old sand in the joints, you’ll need 5-6 bags of kiln-dried sand.

Also, it should be a very accurate number in your case as the joints are going to be the same for most block paving jobs because mostly block pavers are 50mm thick and installed with little to no gaps between each other. But in some cases, if you’ve wider joints to fill, you’ll need more bags than usual.

If you’re a DIYer doing block paving yourself, check out the DIY cheat sheet for block paving here, there’s a lot more you need to know during the process.

Can You Brush Sharp Sand into Block Paving Joints? Is there any kiln-dried sand alternative to use between block paving? It’s recommended to only use kiln-dried sand between the joints of your block paving because it’s meant for that purpose. Using any other type of sand like sharp sand, silver sand, and building sand between block pavers could lead the sand to wash out of the joints very quickly. So, do it once do it right.

Re-sanding Block Paving: How much kiln-dried sand you need?

Honestly, whether you sand your block paving for the first time or re-sand it after cleaning it a couple of years later, you’ll require nearly the same amount of kiln-dried sand because there’s nothing much left inside the joints after you clean the paving with a pressure washer.

Hence, you require the same number of kiln-dried sand bags, which might be a little less to re-sand a block paving as if you were sanding it for the first time depending on how much old sand you left into the joints while cleaning. That’s one bag of kiln-dried sand (25kg) that should cover the joints within 8-10m2 of block paving to re-sand.

FAQs

Does Kiln Dried Sand Stop Weeds?

I’ve never seen someone saying that kiln-dried sand stops weeds between the block paving and it’s true because no matter what you’re going to do to prevent weed growth, weeds are supposed to grow there. There’s special kiln-dried sand to stop weeds from growing that costs way more than normal kiln-dried sand but honestly, it doesn’t work.

Should I First Sand or Seal Block Paving?

Sealing is always done after sanding the block paving. Sealing will help the sand to last longer between the joints and also enhance the overall look of the block paving. Sealing is the best way to protect your block paving from staining and it’s much easier to clean later on. You can immediately seal block paving after sanding as long as the kiln-dried sand above the pavers is brushed off and the block paving is totally clean.