Building a Wood Carport can be a simple job when setup right. This article will walk you through the construction for building a standard size carport 10-ft x 20-ft carport to provide protection from the sun, wind, and rain with 200 sq ft of coverage.
The first thing that needs to be done is to figure out a square box to build the carport to, when your in square both corner to corner measurements are the same. Next figure out the height of the carport based on the needs of the car or trucking parking under it. Dig 6 holes one in each corner and one on both sides of the center in line with the corners on the long wall [20']. Mix the concrete then pour it into the holes in the ground leveling and bracing each post as you go.
After your 6 posts are set, [it should look like fence post in the ground] Start by building your first 2x10 on top of the 6 post to the outside edge of the 4x4 post, after the first box is built run another box on top of the post this time on the inside nailed to the inside of the first box built. It would be best to run a few straps on the inside corners strapping the 2x10 to the 4x4 posts. At this point you should see 6 posts sticking out of the ground with a box on top flush to the outside posts.
The roof, now most people don't have any idea how to build a roof, we will cover a very simple way you could build a roof for a carport. [note: this way will not be useful for anything besides a carport or doghouse, etc,] First measure then mark the center of the front and back walls, Then nail a 2x10 standing up level on the 2" side from the front wall to the back. [that is the ridge board] Since this is a carport and most people do not know the math to calculate rafters we will make it very simple. Measure from the side wall over to the 2x10 ridge, our example is 10' wide and the measurement to the ridge is 4'11-1/4 [that measurement is the [RUN] also our rafter measurement. next lay out a 2x10 over the [RUN] then make a line from the top of one corner over and across to the bottom of the other corner. you should have two cuts, one at the [RUN] measurement the other is a corner to corner cut. After making them cuts you should have two rafters that go from 10" to 0", nail the 10" side to the ridge the other side ends at 0" right at the top edge of the 2x10 box. Run the rafters 16" on center down both the left and right sides of the 2x10 box
Finish by sheeting the roof with 1/2" OSB, use 8-D nails avg. 36 nails per sheet to know its nailed down right, next add paint to seal the wood, then shingles to cover the roof. That's it we can call it a job well done.