I need some advice on sizing a porch roof with two pillars.
The idea is that it will be about 4.40 m wide (covered with boards and metal), and the depth of the porch is approximately 1.65 m, so I assume the roof beams will be slightly longer. The roof angle is 18 degrees, snow zone 2.5. My question is what dimensions I need for the front beam between the two pillars at the front, as well as for the roof beams? I have a drawing from the house manufacturer, but it specifies three pillars (with 90x225 on top), but my partner wants two...
You should probably clarify how you envision the construction. As I understand your description, the front beam has no load-bearing function. That task falls on the side beams and the rafters. Post your drawing, and it will be easier.
The front beam rests on the columns, which in turn support the roof trusses. A canopy roof with two columns, basically like this roof:
But without the middle column then. So, with two columns and a span of 4.40... what is required for the dimension of the glulam beam do you think?
A size of 90x270 is sufficient, but it is not wrong to oversize. The snow load on such a roof can be difficult to calculate since there is a roof above.
Thank you for your calculation! That was nice to hear. Unfortunately, my drawing does not indicate the dimensions of the roof trusses, but I guess 45x170. Does that sound reasonable? The length should be around 1.8 m approximately.
