Hello everyone,
we are about to order a patio roof with wall mounting.
Two posts obviously need to be secured on the patio with foundations.
Our patio has a concrete slab laid on a gravel bed.
The manufacturer of the roof recommends two isolated footings with a diameter of 45cm (18 inches) and a depth of 80cm (31 inches).
I remember how heavily the gravel for our patio was compacted (which is of course a good thing) – I’m just wondering how I am supposed to dig 80cm (31 inches) down here.
Could I possibly use the compacted gravel as a foundation already – or is it really necessary to go 80cm (31 inches) deep? How would you approach this?
we are about to order a patio roof with wall mounting.
Two posts obviously need to be secured on the patio with foundations.
Our patio has a concrete slab laid on a gravel bed.
The manufacturer of the roof recommends two isolated footings with a diameter of 45cm (18 inches) and a depth of 80cm (31 inches).
I remember how heavily the gravel for our patio was compacted (which is of course a good thing) – I’m just wondering how I am supposed to dig 80cm (31 inches) down here.
Could I possibly use the compacted gravel as a foundation already – or is it really necessary to go 80cm (31 inches) deep? How would you approach this?
S
Simon-18916 Jul 2025 11:40Musketier schrieb:
We didn’t cut the slabs; we had holes drilled through them.
Nothing broke for us, but our patio slabs are also 8cm thick. With 8cm (3 inches) slabs, I would be less concerned as well.
Musketier schrieb:
Aren’t they always fixed on the inside? At least on ours, you can’t see anything. Externally fixed anchors are easier to access from a construction and installation perspective.
So I wouldn’t rule that out completely. It’s quite possible that some manufacturers take care to fix anchors on the inside.
I also think I’ll start by making the foundations and then screw the posts of the canopy onto them. After that, I’ll cut the boards and place them around. It should work fine. Using an angle grinder with the right blade should make it manageable.
The question is what to use as a foundation. Ultimately, a 40mm (1.5 inch) pipe seems reasonable, which I can simply set into the ground (maybe with an aluminum profile underneath to keep everything level) and then fill the pipe with concrete, right?
The canopy weighs about 550kg (1,210 lbs). It will have two posts and be attached to the wall by the terrace. In the end, there are hardly any significant forces acting on it—especially for a "light" canopy.
For me, the main thing is probably to dig deep enough!
The question is what to use as a foundation. Ultimately, a 40mm (1.5 inch) pipe seems reasonable, which I can simply set into the ground (maybe with an aluminum profile underneath to keep everything level) and then fill the pipe with concrete, right?
The canopy weighs about 550kg (1,210 lbs). It will have two posts and be attached to the wall by the terrace. In the end, there are hardly any significant forces acting on it—especially for a "light" canopy.
For me, the main thing is probably to dig deep enough!
One more question: If I place the post directly on the concrete foundation, won’t there be quite a steep slope since my slabs are 5cm (2 inches) thick and the cut slabs still need to be set into the gravel bed so that everything is level? This means the foundation should be 5cm (2 inches) lower than the top edge of the patio slabs.
Is this basically standard practice and does it ultimately provide the slope I need, or is there something else I should consider? If I drill through the slabs, I’ll be sitting much higher and would then need to install the wall mounting higher as well, correct?
Is this basically standard practice and does it ultimately provide the slope I need, or is there something else I should consider? If I drill through the slabs, I’ll be sitting much higher and would then need to install the wall mounting higher as well, correct?
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