ᐅ Experience with 3 cm thick patio slabs – do they break easily?

Created on: 20 Jul 2022 10:08
Y
Ypsi aus NI
Hello, yesterday we talked with a mason / all-rounder about our terrace. We are planning to use slabs measuring 60 x 120cm (24 x 48 inches) with a thickness of 3cm (1.2 inches). He advised against this. According to him, because of the thickness, the slabs cannot be compacted with a plate compactor without breaking. He also said that the base would gradually settle over time (even if it was compacted without the slabs beforehand), creating voids that would cause the slabs to become loose.

Does anyone have experience with this? Specifically, have such “thin” slabs been installed for a longer period, and can confirm or deny this?

Thank you!
Y
ypg
21 Jul 2022 00:19
Offtopic schrieb:

Don’t the edges crack if they are installed without a gap?
No. Nothing has cracked or chipped. These are also high-quality slabs from a natural stone specialist supplier... but they are open-pored 🙄
D
DaveG74
28 Nov 2022 07:30
A quick question: what exactly is meant by a mortar bed including drainage? What is the detailed construction of such a mortar bed?

Thank you!
B
Benutzer 1001
28 Nov 2022 08:50
Simply use gravel or sand with a grain size of 1-3mm (0.04-0.12 inches) and mix it with cement.
Y
Ypsi aus NI
11 Mar 2023 12:46
We have now had several landscape gardeners visit, and we will have these thin slabs glued down so that nothing hopefully sinks and no cracks develop.

On the west side of our house, we have two windows, each 3m (10 feet) wide (lift-and-slide doors). The west side is our weather-exposed side, and we plan to build a terrace along the entire 12m (39 feet) width.

One landscape gardener insisted on installing a drainage channel along the house wall to keep moisture away from the masonry. According to him, the normal slope of the terrace would not be sufficient during heavy rainfall. With the channel, the rainwater would immediately drain away and would not be able to damage the foundation.

We asked all the other landscape gardeners about this, and none of them have ever installed drainage in a terrace.

What do you think? How have you handled this? Is drainage needed on a terrace directly adjacent to the house?
W
WilderSueden
11 Mar 2023 16:21
You basically only need drainage directly in front of doors. The masonry must be sealed up to 30cm (12 inches) above ground level anyway, but you should consider the ground level that was discussed earlier. If everything is done properly, it’s not a big problem if water stands briefly against the wall during two thunderstorms per year.