This was a rare non-riding Sunday, as I wanted to continue with my carport project before the next rain on Monday! I made some good progress today and really surprised myself with how well it’s been going, since this is my first real attempt at carpentry. I’d been wanting to do this for a long time, but wasn’t sure if I could do it myself, and didn’t want to mess it up then have to take it all apart!
I also mulled over endless configurations and designs, and decided on this one. It’s simple but still looks nice. I factored in 1/4" per foot downward angle for water runoff, since I’ll be putting corrugation on top when it’s done. (Google really came in handy for a lot of stuff!)
I quickly found that having the right tools is essential, and taking your time! Some of the tools I used for the job were: quick set cement, a carpenter’s level, a miter chop saw, circular saw, jig saw, saw horses, drill, drill press, various screwdrivers and sockets, and routing bits for counter sinking, and more. It was really a challenging getting 16 foot 2x6 planks in my prius, but I did!
Still have to complete the top but it looks really good so far!
haha, how did you know I was planning on taking my uni up there!? By joist do you mean the 4x4 angle braces in the front? I do plan on putting two more just in back of the front posts going the other direction, plus I’m thinking I should put two in back and two more in front going left and right for bi-directional stability. Do you think that would be a good idea, or will the top pieces accomplish that?
Joist generally means the horizontal boards on the top. Often the last one is doubled for extra strength.
I don’t think you need more bracing. Tying in the left brace to the house overhang support like you have should give sufficient side-to-side stability.
If you wanted to beef up the structure I would consider nailing something under the white “beams” as all the weight of the roof looks like it is being held by 4 bolts plus whatever you have on the bracing (I can’t tell). I really don’t know how strong it needs to be since we build everything with snow loads in mind.
So are you going to drop onto one of those garbage bins or going to the flat?
haha, I’d be afraid it would collapse! Yeah, I originally had two 2x4 boards “sandwiched” at the top at each post, but removed one of each while attaching the main 2x6 beams.
I plan to reattach those at the top of each post. Part of the intial reason for doing this was so I could insert 4x4 angled supports between them, like I did in the front. I also thought about cutting short pieces of 4x4 to attach between the long 2x6 beams, to have a good solid structure for attaching the top boards, and also to keep the dual 2x6 beams from warping.
The other option would be joist hangers, but I like the 4x4 idea better since it supports both the top boards and adds stability to the 2x6 means as well. The 4x4 pieces would be flush with the bottom of the beams, and rise above them enough to attach the top boards to them.
Does anyone know how to determine the optimum distance between the top horizontal beams? There will be only lightweight corrugated panels on top, of those, so the entire top structure will be pretty light. The carport is about 9 feet wide and 13 feet long. So I just made a rough guess that one top joist every 16" would be good. Can they be farther apart or should they be closer?
Most roof truses / rafters / (horizontal members in this case) are set at 24" centers. As you are using a fairly flat roof structure i.e. not a lot of slope for a heavy rain to come off of quickly it would be best to stick with the 16" centers. As Sask has mentioned we build roofs here with snow load in mind. If you haven’t already done so it might not be a bad idea to look into your local building codes to get a better idea of what might be expected of your structure should a building inspector happen to wander by.
Edit: I see that Eric has mentioned 18" centers. 18" centers will probably not line up well with most sheating materials.
Thanks guys. Not sure what you mean by “centers”. The corrugated panels are lightweight (not steel) and come 24" wide by about 96" long. I will overlap them when installing but still the total weight will be very low. I’d like to go as wide as possible with the top beams to keep weight at a minimum, but avoid any sagging of the panels. They will be running length-wise so water will run off easily. I built the carport a downward pitch of 1/4" per foot, which I’m told is plenty for a corrugated top.
This is a rough idea I had of attaching cross pieces between the horizontal joists, rather than single long beams crossing over the top. These short pieces could be attached from the bottom, once the top is covered with the panels. It would give additional support to the panels and the structure in general. (Looks like bricks, haha).
Center-to-center. Think of a crank arm (to use a unicycling metaphor). they are measured from center to center. In construction, measure from the center of one piece of wood to the next; the fasteners go on those centerlines.
For roof strength, consider if you’ll ever need to go up there. It’s a pretty small carport, but if you want to walk or ride on it, consider adding some (flat) plywood under the corrugated stuff. You could also use plywood as an alternative to all those little cross pieces. Might be easier, though plywood isn’t cheap…
Consider the patio cover we had put in a few years ago. Aluminum roof keeps the elements off, but you can’t walk on it. I can’t get out on it to clear off the leaves that pile up in the channels up there. So they pile up. There will be no unicycling up there.
Thanks for that info John. I won’t be going on top to ride, walk or any of that. (Too a scared! :o) Today I decided to end notch the top boards for a more secure fit and easier attachment. Getting the notches straight and just the right size was a challenge! Then more painting.
Next task will be to put cross beams between the horizontal joists, every 24" (which is width of corrugated panels) then finally install the panels. It’s really looking good so far!
By joist do you mean the 4x4 angle braces in the front? I do plan on putting two more just in back of the front posts going the other direction, plus I’m thinking I should put two in back and two more in front going left and right for bi-directional stability. Do you think that would be a good idea, or will the top pieces accomplish that?
Yeah, I originally had two 2x4 boards “sandwiched” at the top at each post, but removed one of each while attaching the main 2x6 beams.
