ᐅ Laying Patio Slabs and Preventing Weed Growth

Hello everyone!

I want to build a patio using 40x60cm (16x24 inches) slabs of the type "Pallas grassano." This is my first time doing something like this, so I have a question: what is the ideal base for it? Gravel or crushed stone? What size or grain size should it be? How thick should the layer be?

I don’t want to have to constantly pull weeds out of the joints later on. What is the best way to prevent this? A friend said that even if I lay the slabs tightly together, plant growth could still develop in the cracks, and he recommended grouting the slabs with mortar. That seems a bit complicated to me... How would you approach this in my situation?

We don’t have mortar between the slabs, so weeds and grass keep growing in the gaps. It’s not really a big issue, though; you just have to remove them occasionally. What stopped us from filling the joints was the fact that if a slab ever breaks, looks worn, or if you simply want a change, it’s easier to replace the slabs...

If using mortar is too labor-intensive, just skip it. Then lay the slabs edge to edge and occasionally pull out any weeds.

That looks good when a bit of greenery shows through. I also don’t have any mortar between these stones. A little bit of weed isn’t a big deal.

I would be bothered by the weeds, so I filled the joints with grout. The base layer is gravel, and proper compaction is important. The aggregate size is 32 mm (1.25 inches), and I applied it in a 10 cm (4 inch) layer. Everything is stable, looks good, and there are no weeds.

The joints are not the problem, and if a slab breaks, it can easily be replaced. I have already relaid the entire terrace and removed the old slabs. That went very well. What bothers me is the weeds growing between the slabs.