Hello!
I am about to build my terrace roofing. I am still unsure about how to fasten my 8x20cm (3x8 inch) wall beam to the house wall.
Regarding the house wall:
- 17.5cm (7 inches) aerated concrete
- 16.0cm (6.3 inches) insulation
- 4.00cm (1.6 inches) air gap
- 11.5cm (4.5 inches) facing brick
However, the fastening will not be done in the aerated concrete, but directly above the 6.5m (21.3 ft) terrace window (and the external roller shutter housing) in the lintel. Because the construction documents (we bought the house, not built it) do not specify the material of the lintel, I do not know whether I will be fixing the terrace roof into concrete, aerated concrete, or something else. The house is from 2012, so alternatives to reinforced concrete lintels were already available then.
For this reason, I am leaning towards the “classic” solution for fastening: M16 threaded rods, 530mm (21 inches) long, made of stainless steel grade A4, fixed with Fischer FIS V 300 T injection mortar. I would also use a 40cm (16 inches) long metal sleeve with a sieve opening.
First question: This is the standard solution for aerated concrete. Is it also appropriate if the lintel is made of concrete?
As a second option, I am considering anchor bolts of the same length. This would allow me to skip the injection mortar. However, I seem to recall that these anchor bolts are not approved for aerated concrete. So if the lintel unexpectedly is not concrete, I would be in a difficult situation.
Second question: Is my memory correct, or am I mistaken?
Third question: Can you suggest any alternative fastening methods?
Fourth question: Is the injection mortar I mentioned the correct one? There are so many variants, perhaps someone here is familiar with it.
Best regards
I am about to build my terrace roofing. I am still unsure about how to fasten my 8x20cm (3x8 inch) wall beam to the house wall.
Regarding the house wall:
- 17.5cm (7 inches) aerated concrete
- 16.0cm (6.3 inches) insulation
- 4.00cm (1.6 inches) air gap
- 11.5cm (4.5 inches) facing brick
However, the fastening will not be done in the aerated concrete, but directly above the 6.5m (21.3 ft) terrace window (and the external roller shutter housing) in the lintel. Because the construction documents (we bought the house, not built it) do not specify the material of the lintel, I do not know whether I will be fixing the terrace roof into concrete, aerated concrete, or something else. The house is from 2012, so alternatives to reinforced concrete lintels were already available then.
For this reason, I am leaning towards the “classic” solution for fastening: M16 threaded rods, 530mm (21 inches) long, made of stainless steel grade A4, fixed with Fischer FIS V 300 T injection mortar. I would also use a 40cm (16 inches) long metal sleeve with a sieve opening.
First question: This is the standard solution for aerated concrete. Is it also appropriate if the lintel is made of concrete?
As a second option, I am considering anchor bolts of the same length. This would allow me to skip the injection mortar. However, I seem to recall that these anchor bolts are not approved for aerated concrete. So if the lintel unexpectedly is not concrete, I would be in a difficult situation.
Second question: Is my memory correct, or am I mistaken?
Third question: Can you suggest any alternative fastening methods?
Fourth question: Is the injection mortar I mentioned the correct one? There are so many variants, perhaps someone here is familiar with it.
Best regards
Buchsbaum066 schrieb:
That’s how I would do it too. In theory, the vertical supports could also be recessed into the insulation. This option is ruled out because then the supports would stand in front of the 6m (20 feet) window wall. But yes, otherwise it would be a practical solution.
S
Simon-18930 Oct 2024 12:17bra-tak schrieb:
I need to clarify something here:
If I have a protective sleeve and injection mortar in the area of the facing bricks as well, then the threaded rod also rests on the outer wythe. This means it transfers lateral forces into the brick wall, which in my opinion is not problematic. Only compressive and tensile forces need to be avoided in facing walls.
If my reasoning is correct, then there would still be 20cm (8 inches) of free threaded length between the brick and the structural wall, but the bending stress would be significantly reduced due to the additional support. I have to admit, I have never dealt with facing bricks before. So I will assume it’s “nothing” for now.
S
Simon-18931 Oct 2024 13:01bra-tak schrieb:
However, it is not fastened in the aerated concrete, but directly above the 6.5m (21 ft 4 in) terrace window (and the external roller shutter housing) in the lintel. Is that a continuous window without any concrete or masonry support underneath? Does the lintel span the full 6.5m (21 ft 4 in) freely?
If so, consulting a structural engineer would definitely be necessary!
I recalculated the bending of the threaded rods in M16-24 yesterday evening. Result: I am installing two posts under the wall plate.
As an engineer, you eventually recognize when you can no longer justify something with calculations.
With snow loads, the deflection was completely unacceptable.
As an engineer, you eventually recognize when you can no longer justify something with calculations.
With snow loads, the deflection was completely unacceptable.
N
nordanney31 Oct 2024 19:31bra-tak schrieb:
With snow loads, the deflection was beyond acceptable limits.That surprises me, since you also have the load transfer in the brickwork. Are there no posts in the front, meaning the support is only the attachment, like with an awning?nordanney schrieb:
That surprises me, because you also have the load transferred onto the facing bricks. Are there no posts at the front, so is it just the attachment like with an awning?I spoke again with a local bricklayer, and he strongly advised against simply resting the threaded rods on the brick veneer. The problem is, as mentioned, the brickwork there consists of only 4 courses down, and then there is the large window front. The risk that the brick veneer could be pulled downward by up to 3 kN per threaded rod under snow load is too high.Similar topics