OV9

I have jet-washed monoblocking many times.

I have re-sanded monoblocking after cleaning it many times.

I've tried mixing something (can't remember what at the moment) in with the sand in an attempt to reduce weed/grass growth in the joints, but it wasn't very effective.

I have never used a sealant at the end of the process.

I did watch "a professional" clean a neighbour's drive a few years back. They did a decent enough job, but the sealant that they applied after re-sanding looked suspiciously like water that they lightly sprinkled on with a watering can. I wasn't convinced it did much I was under the impression that sealant was intended to provide an anti-fungal coating on the surface of the block, but I became aware recently that some/all of them are more focussed on solidifying the sand in the joints in order to prevent it being blown/washed out, and to "inhibit organic growth". This may not be news to some of you, but to me it was an.... AH.

So this time I tried some of this stuff this stuff. Opted to apply it with a roller. It looks quite like milk and smells a bit like PVA glue. Which makes me wonder if it is a variant of PVA glue? I'm pretty sure it's not a variant of milk. Dunno.

Unfortunately I under-estimated how much I'd need. 20 litres covered around 85% of my blocking The good news is that - whilst I wait for more to arrive - I can confirm that the sand has indeed firmed up nicely (contrasting markedly with the loose sand in the untreated area). It claims to be a matt finish, and it is - you can see the line where I ran out, but it's not glaringly different.

So lets see if it actually lasts any longer before picking up weeds/moss/ingrained dirt........

More exciting product reviews. As they happen. Here on ov9.

I have a lot less mortar/grout/whatever left between my patio slabs and drive blocks after jet washing a couple of times. I took note of this video when I saw it - 11 months old apparently, so nearly a year ago - and thought it would be a heck of a lot of work to do it properly myself. So I haven't:



That's really for the patio slabs but the drive blocks aren't intended to have big joins so I presume I should just be brushing dry sand into them and that's it. I always thought sealer was to stop the blocks being porous so any oil drips or whatever didn't stain them forever. Do update us.

I was just going to mention Sika but I don’t think you can get it to fit in traditional block paving. It’s pre mixed with resin so rather sticky.

Yeah, I appreciate it's for a different type of surface but it's semi-related.

Jobbo wrote: Fri Jun 13, 2025 10:00 am I took note of this video when I saw it - 11 months old apparently, so nearly a year ago - and thought it would be a heck of a lot of work to do it properly myself. So I haven't

Great finished result, but yeah - takes a lot to achieve it even on a handful of slabs.