Even with the crown “up”, this size beam with that span will sag over time at that span. The weight of the beam itself is too much for that span.
Lots of good comments.
I try to follow the advice of one of my past instructors…it’s not what you say, but how you say it.
I always try to give as complete a picture of a condition, as found here, but without crossing the expertise line. I would never be specific about undersizing, structual soundness, lifespan, etc., if making that statement elevates me to an expertise level I can’t backup in court. I would always defer to the expert, in that particular catagory of concern. I think that’s what my Client is paying me to do…make good judgement decisions on his/her behalf, AND C Y A.
This appears to be a close call, and the beam has been functioning for quite some time. Not trying to stir the pot, I’m just saying if you know that the size of the beam is too small, then shouldn’t you know what the correct size is? How do you know it is too small then? With a close call like that, just make sure your not making mountains out of anthills.
On the other hand, maybe you’re right not getting in too deep. Just call out a concern and get an engineer to evaluate. But I see it as a catch 22, being able to say it is too small without knowing the adequate size, which was the case here. The reason question this a little is because it is a close call, and the age of the home, and the design techniques utilized then, and the fact that the support is functioning as intended. Who knows? Ahh, the power of discussions.
Just a thought, if collar ties are persent inside the garage at the top plate would that not transfer most of the bearing wieght to the end walls and not the gable over the garage door. I also doubt it’s a 21 ft. garage door opening.
The original post specified that the garage had a ridge BEAM supported by a post which was in turn supported by the header. No, the door may not be 21 feet wide, but the garage may be, and therefore 10.5 feet of the roof load, divided by 2, is coming down on that post and being transferred to the center of the header. If it had a “ridge beam”, presumably it has no collar ties.
You are absolutely correct, Richard. Also, the garage door header span is 16’, as stated in the original post.