Hello!
We are going to install an entrance canopy on a cavity wall made of mexicana brick. The house is from -66, and as far as I know, mexicana brick (or lime sandstone) is quite a fragile material. We already have a few cracks through the bricks as it is.
There will be four sturdy screws to hold up the entrance canopy. Should I preferably drill directly into the brick or rather into the mortar in between? Will this hold, or should I preferably ensure to reach a stud behind the cavity wall for better stability? The canopy is fairly lightweight, aluminum and plexi, width 1500 mm.
We were planning to rent a Hilti drill this weekend; I assume a regular drill wouldn't be up to the job.
Grateful for a quick reply!
We are going to install an entrance canopy on a cavity wall made of mexicana brick. The house is from -66, and as far as I know, mexicana brick (or lime sandstone) is quite a fragile material. We already have a few cracks through the bricks as it is.
There will be four sturdy screws to hold up the entrance canopy. Should I preferably drill directly into the brick or rather into the mortar in between? Will this hold, or should I preferably ensure to reach a stud behind the cavity wall for better stability? The canopy is fairly lightweight, aluminum and plexi, width 1500 mm.
We were planning to rent a Hilti drill this weekend; I assume a regular drill wouldn't be up to the job.
Grateful for a quick reply!
A facing wall of Mexi sandstone is 100 mm 'thick'. Depending on how the sandstone is attached to the frame and how much the canopy weighs (causing a pulling moment on the two upper screws), it might not be suitable at all to attach them to the facing wall, regardless of whether it's done in the joint or the stone.
I suggest you do this instead:
Try to locate standing studs in the frame and drill clearance holes for a 15.2 mm plastic VP pipe. Then insert a piece of VP pipe into the holes and run a bolt straight into the frame from the canopy. The two lower screws do not take tension but instead take pressure and shear forces. Therefore, you can attach them to the facing wall regardless of whether it's in the stone or the joint. Any potential wind lift on the canopy is partially offset by the roof's own weight. The risk of pullout on the two lower screws should therefore be considered unlikely compared to the upper ones.
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The Builder
I suggest you do this instead:
Try to locate standing studs in the frame and drill clearance holes for a 15.2 mm plastic VP pipe. Then insert a piece of VP pipe into the holes and run a bolt straight into the frame from the canopy. The two lower screws do not take tension but instead take pressure and shear forces. Therefore, you can attach them to the facing wall regardless of whether it's in the stone or the joint. Any potential wind lift on the canopy is partially offset by the roof's own weight. The risk of pullout on the two lower screws should therefore be considered unlikely compared to the upper ones.
_______________
The Builder
One aspect might be a thermal bridge and even more seriously water intrusion into the studs? Got another tip to drill only in the facade but attach with anchor adhesive, plug, and then screw to secure the entrance roof.
Maybe it's a better option, especially if it's tricky to hit the studs while wanting a certain symmetry on the roof.
/M
Maybe it's a better option, especially if it's tricky to hit the studs while wanting a certain symmetry on the roof.
/M