I'm about to start building the deck but feel uncertain about the dimensions of the deck roof. I have a house with a roof pitch of 47 degrees, so there will be quite a bit of snow on the deck roof since I live in Västernorrland.
The plan is for the deck to stand on garden slabs/lecablocks and all joists and beams are in the dimension 195x45. What do you think, will this work?
That will probably be strong and good. Place a 45x45 against the load-bearing beam that comes on the house wall, cut out and let the roof beams rest on it, so it looks nicer. I think so.
That will probably be strong and good. Place a 45x45 against the support beam that comes on the house wall, saw out and let the roof beams rest on it, it will look nicer. I think.
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Old thread... But if you make such a cutout. Doesn't that cause a weakening? I think the beam might split at the saw cut. But maybe the dimension is just well chosen to reduce bending and therefore won't be affected by a cutout.
Old thread... But if you make such a cutout, doesn't it weaken the structure? I think the beam might split at the sawcut.
But maybe the dimension is just adequately large to reduce bending, and therefore a cutout won't affect it.
It will only make a marginal difference. The cutout is at the end of the beam, there's almost no vertical load along the house wall at all. The risk of it splitting is negligible.
There will only be a marginal difference. The notch is at the end of the beam, there's hardly any vertical load along the house wall at all. There's no risk of it splitting.
That is a completely incorrect statement. There will be a significant vertical load that needs to come down there if a lot of snow accumulates on the roof.
As pointed out, it will indeed be a weakening to do it this way, and I think it's best to calculate this or choose another solution.
That is indeed an entirely incorrect statement. There will be a significant vertical load that needs to come down if a lot of snow accumulates on the roof.
As pointed out, it is a weakening to do it this way, and I think it is best to calculate this or choose another solution.
If the roof is flat. Since you have a roof slope, the minimum vertical load will be at the highest point of the roof.
And since the end grain is snug against the rule along the wall, the cutout will only marginally weaken it.
If the roof is flat. Since you have a roof slope, the minimum vertical load will be at the highest point of the roof..
And since the end grain lies flush against the rule along the wall, the notching will only weaken it marginally.
Can you explain why you mean there will be less vertical load at the highest point? In this case, most of the vertical load will obviously be directed downward at the central support, but the vertical load will not be less because the roof slopes.
And how do you mean that it matters that the end grain is against the upper beam? The columns under the outermost beam are not moment-resistant in their attachment. You cannot count on them "holding against," so to speak. And even if they did with the help of diaphragm action or bracing, I would argue that it does not affect the risk of splitting at the inner support.
What I mean is merely that this type of "notching" of beam elements is a textbook example of how not to do it. Then I might agree that it looks better aesthetically, but you must then verify that it actually holds according to the design rules that exist.
The construction is unsuitable for several reasons. The risk of cracks in the notch is significant. It would have been better if the studs on the wall were positioned a notch lower so that the entire beam would be supported. Then one must consider that there can be quite high shear forces at the support, especially in Västerbotten, which requires a sufficient amount of material in the beam. A 45x145 C 24 beam can withstand a shear force of up to approximately 8 kN (Träguiden) which is a fully possible figure for a roof beam in Västerbotten. If you notch, the capacity is reduced accordingly.
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