turning a section of my deck into a gazebo
Spriing35
| Posted in General Discussion on
I used 4×4 posts for the legs on my deck, which is only about 2 feet off of ground level with at least 2 feet in the ground surrounded by concrete. I am now wanting to convert a 10×12 section of said deck into a gazebo, or maybe a roof with some railing is a better description. My question is this, I was thinkingabout replacing each of the 4 corner legs with 4x4x16 legs, to add a roof. Or should I go with an overlapping joint and bolt system with some metal plates. I have no idea if that would be strong enough to support a 10×12 roof.
**Edited for spelling
Replies
I am not up to date on the proper lingo but the joint would look something like this.
It all depends on where you live, and what kind of roof you are thinking of, how the existing posts are set on what kind of soil.
And of course, the spacing of the posts.
I live in Joplin MO area, I will attach a picture of the roof style I was going with as I do not know the name of it, the posts are set in holes 12 inches in diameter and 2 feet deep in concrete, the outside posts are spaced at 10 ft and 12 ft. I do not have additional posts in a linear line between them but there are support posts in the center of the deck.
I think you need something like in the photo, with more supports than four corner 4x4s. 6x6 might work.
Posts probably need to be deeper too. two feet seems a little shy of frost depth. with longer posts, you may want to be deeper to keep the posts vertical, unless you are careful in roof construction to make the roof handle the cross-stresses (not just rest on the posts)
the open sides will challenge building a structure to handle snow load and to stay put in the wind.
this is what my deck looks like.
How deep would you recommend the holes be, inspector said 2 feet when I put the deck in but that was before the roof. Also attaching a picture of a layout with possible new design on additional posts. My main issue with the 6x6 posts is finding them longer that 12 ft. Lowe's doesn't carry them any longer than that. May have to look at some other lumber yards. Also our frost line in 18 inches.
ncleMike42 thank you for all of your feed back.
https://www.google.com/search?client=firefox-b-1-d&sxsrf=ALeKk02Qp2AeHLlBqQ8_U6a9Bq08fAZxhA%3A1592066075030&ei=GwDlXofMAfuawbkPgYSR8Ao&q=Joplin+MO+frost+depth&oq=Joplin+MO+frost+depth&gs_lcp=CgZwc3ktYWIQAzIECCMQJzoECAAQRzoECAAQQzoHCAAQFBCHAjoHCAAQsQMQQzoFCAAQsQM6AggAOgYIABAWEB46CAgAEAgQDRAeUOEWWK4vYP8xaABwAXgAgAGLAYgBvQaSAQQxMS4xmAEAoAEBqgEHZ3dzLXdpeg&sclient=psy-ab&ved=0ahUKEwjHxfGmnP_pAhV7TTABHQFCBK4Q4dUDCAs&uact=5
My google fu says the frost depth should be 30 inches.
what you might want to do is instead of planting the post and surrounding with concrete is to fill forms with concrete as a base, then transition to the wood post with a suitable connector. (search for 6x6 post base)
then you should have no issues getting the length you need.
then you will want to either install cross-braces at the top, or make the Header tall enough to carry the stress. (my money is that cross braces at the top corner will be better and a lot cheaper.)
https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.yardistrystructures.com%2F12-x-12-wood-gazebo-with-aluminium-roof%2F&psig=AOvVaw3vNdEgKxjtI41fXEZMh2I4&ust=1592153157130000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCNDjze6e_-kCFQAAAAAdAAAAABAF
You can check building codes for span information.
And you can leave the existing deck inside the perimeter of the new posts that support the roof if you like.