Question
We are DIY homeowners installing a paver patio using manufactured stone pavers ranging from 12x12 to 24x24. We already have 1/4 of them down using masonry sand (fine grains) as the bedding sand. Just realized that concrete sand is preferred. We already had plenty of the masonry sand delivered. Is the neagatives of the masonry sand strong enough to switch to concrete sand (to include pulling up the already laid pavers)?

Answer
Hello,

There is a good chance that the masonry sand you have layed under the pavers will not drain adequately because of the fine particle size and so yes, concrete sand would be more suitable for the purpose.   My advice would be to take them up and use the masonry sand in the joints only.  The masonry sand is well suited for use on joints as it lowers the amount of water that gets under the pavers and will not settle out as much as a coarser sand.

The water retention of masonry sand is high because of the tightly interlocking paricles and so if this water freezes the pavers will be forced out of place.  You could also experience flooding during heavy rain since the infiltration rate of the water will be slowed down.

You will of course have to find a new use for the leftover masonry sand,but I would consider that better than having drainage problems with your patio. Good luck. Write back if you have further questions.

Mark  Harshman
http://www.mahdrafting.com
Email: [email protected]

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