I am going to build a canopy according to the following.
Width (along the house) 4 meters, depth (out from the house) 3 meters.
A 4 m long wooden beam (e.g., 45 x 145) is fastened to the house wall, about 2.5 m up on the wall.
3 meters out from the house, I will cast two footings ("one in each corner") and attach posts (e.g., 2 nailed together 45x95) to them. NOTE! I want two posts, i.e., one post at each end of the roof. I do not want three posts, i.e., with one in the middle.
Between the posts, I will then have a 4 m long beam of some kind. The beam will extend 25 cm beyond each post, i.e., the distance between the posts is 3.5 meters.
From the wooden beam on the wall to the wooden beam between the posts, I will then lay 3 m long roof joists (e.g., 45 x 145) with a max center-to-center distance of 120 cm.
On top of the roof joists, there will be roof boards, felt, and standing seam metal roofing.
My question is what dimension I need for the beam between the posts.
One option is, of course, glulam (possibly 42 x 180 or 56 x 180).
Another option is to use regular joists, and then option one is to use one joist (e.g., 45 x 195), and option two is to use two nailed-together joists as a beam (e.g., 2 pieces of 45 x 145).
What do you think is required for the beam and dimensions of the beam between the posts to ensure that it holds and does not sag?
