I'm planning to build a carport attached to my house in the redwood area, and I could really use some advice. The carport will be 20 feet deep and 25 feet wide, and I've got a friend who can help me with logs and a bandsaw mill. Here's the list of lumber I'm considering for this lean-to setup: (6) 6x6 8' posts, (2) 6x8 20' beams, and (16) 4x6 25' "Perlins" spaced on 24" centers. Does this sound like overkill? Or am I missing something important? I mainly need enough space for my minivan, but I want extra headroom for some future projects. Should I go higher with the posts or is that not necessary? What do you all think?
3 Answers
You should consider using trusses that are designed specifically for that kind of span. They provide better support and can handle the load more effectively. And definitely think about consulting with a structural engineer if possible. It's a smart investment to ensure everything is safe and up to code.
Honestly, if you're feeling uncertain and you don't have much experience with this, I think hiring a professional might be your best bet. Wind and snow loads could seriously compromise your carport if it's not built correctly. It might save you a lot of headaches (and potential damage) down the line.
Great point! I recommend checking out the rafter span tables in the building codes. Since redwood is less strong than doug fir or southern yellow pine, it's smart to upsize your lumber. For instance, if the table suggests 2x6s, go with 2x8s. Also, 20 feet is a significant span for 4x6s, so consider adding a mid-span support or using larger wood like 4x8s on 24” centers or 2x10s on 16” centers. Just keep in mind that the total weight will be considerable, and you might want a good shear solution to avoid accidents, especially if someone backs into a post.
Exactly! It's better to overbuild slightly than risk having the structure fail.
I agree! It’s always better to be safe and get it done right.