Joined: July 2004
||Posted: 09 Jan. 2019,11:25
Here's the photie you sent to me....
...and it shows a classic case of a single pack of blocks that are more porous than other packs, and therefore appear damp, and, more worryingly, there has been practically no randomisation of the blocks from this pack with blocks from other packs.
More or less every CBP manufacturer stipulates that blocks should be drawn from a minimum of three packs and randomised prior to laying to even out any variation in shade, texture and porosity. As soon as I see something like this, I know that the installation team is of the "Couldn't Give An Eff" variety.
However, it's not the end of the world. As the blocks dry out naturally and then get re-wetted with rain and suirface water, the interstices (tiny gaps and voids) within the concrete will become filled with micro-particles from the environment and, in 6-12 months' time, they'll be virtually indistinguishable from their neighbours.
Is there a reason why there has been no sand jointing done? It's critical that CBPs are jointed as soon as possible after installation and compliance checks, even if the surface is damp and minimal sand falls into the joints. Some sand, no matter how little, is better than no sand, and the surface can be topped up with further KDS as soon as practical.
It's a bad, bad idea to traffic a CBP surface that hasn't been jointed. The KDS is what locks the surface into place and minimises/prevents settlement.
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