Hi,
I've got 2 areas of paving, one had a gap of 2-3 mm left for filling with fine sand. This now grows weeds in the gaps at a fantastic rate, and I use 12 month weed killer on it every six months, and still they grow. The area must now be worse than Chernobyl.
I'm going to raise all that (with rubber gloves on) and relay it with no gaps, and then water in a mix of fine sand and cement to any cracks left.
The other area is laid with no gaps, but the pavers have a rounded edge. The joints are now all filled with moss, which I blast out yearly with a pressure washer.
You get the point. I hate pavers with gaps.
For 20 mm gravel fill of course you need a 20 mm gap or more, say 30 mm. Pretty soon that will all be lines of weeds, unless you plan to prevent it somehow. Don't know how.![]()