Need Help with Covered Patio

[Robert Stapp]

Hello.


So we are attempting to build a 16 x 20 attached patio. I have a concrete pad so I will be attaching posts to the pad. I plan on running a 2x12 ledger board against the house. I will have 3 posts @ 10ft for the beam. The span from the house to the beam will be 14' with a 2' overhang using 2x6 for rafters. Wife wants a rustic look so it will be covered with Galvanized Steel Utility Panels.


1. Is the 2x12 ledger board the right size?


2. Will running (2) 2 x 10 on each side of the posts hold up the 2 x 6 rafters?


Any help would be appreciated!

[Robert Stapp]

Patio Design.jpg

Hope this helps

[Lee Schierer]

You need to check your local building codes before proceeding. You may need a permit and inspections. Most states have adopted building codes for houses. Your maximum span is dependent on where you live in the country, roof pitch and roof materials. Areas with snow need stronger roof designs.

Here is a guide for rafter spans.

[Joe Adams]

My first thought was are you sure the concrete pad is sufficient to bear the load. You can build it yourself but I'd get an engineer involved to specify materials and consult with a building inspector to make sure you follow code.

[Roger Feeley]

If it's in direct sun, consider tile. That bought us fifteen degrees. Also consider putting up boards on both sides of the posts and covering with plywood and copper flashing. I ran drip irrigation through the channel to water hang plants. You could also store roman shade

[edit]. Better keyboard now. You have the vertical posts. Generally, you put a 2x at the top running from post to post to support your joists.
-- I suggest that you put 2x's on both sides of the post.
-- Then put thin plywood on top to create a box between posts with the open side down.
-- Cover your plywood with copper flashing to keep the plywood from rotting. I did mine about 7 years ago. That thin plywood was still good when I sold the house a year ago.
-- Drill a hole through the posts to connect your upside down boxes.

You can put lighting in there.
I ran drip irrigation pipe through there and used it to water hanging plants. I had a timer on the system. Every morning it gave my plants a good soaking.
You could have rollup shades that are concealed and protected from the weather.

[Bill Sutherland]

Following code is and getting all permits is REALLY important when you sell your house. If you are "repairing" a patio that may be different than constructing one. Find out for sure in your state because it can become a nightmare at the time of sale. Ask me how I know!!

[Chris True]

Where are you at? If you are in the desert this project is not much of a problem. If it snows where you are you have a huge foundation problem, a concrete patio is NOT a foundation to build on. Snow loads can be anywhere from 20 to 60 pounds per square foot.

I looked at something similar a few years ago and wound up going with a 3 panel retractable fabric cover to avoid the footer issue. There were attractive aluminum shade options, and the companies provided engineering for the loads. They had steel insert beams to span the 20 feet i needed but the 2 footers needed were 3*3*3 foot blocks of poured concrete, might have been larger - I forget. The other option was to make the posts closer together, as in a post every 14". No thanks

[Roger Feeley]

Regarding the roof. You can do a rain-proof roof and there were times I wished I had. I chose a layered shade strategy.
-- I had trees providing partial shade.
-- I had lattice over the joists providing partial shade.
-- I had Wisteria and climbing grape vines that filled in the lattice.

By the time you added up all those partials, we were pretty much in full shade.

I would really encourage you to look into covering your concrete with tile. It was great on the feet and a LOT cooler. It could be slippery in the snow, though. I just had to be careful when I swept it off.

[Mark Blatter]

We have been talking about doing something very similar. I got bids from 4-5 companies and all but one said it use 3" rigid foam covered with aluminum sheets. The aluminum gets put on using a spray adhesive and overlaps the joints for strength. I haven't looked yet, but I suspect I can find the materials on line and could put it up myself. However the permitting is a smart piece to include, unless you live somewhere like Montana, in the country, where the only permit required is for electrical.

Here is link to what I refer to;

http://www.screen-house.com/insulated_patio_covers.htm

I haven't read much on it yet, and have no affiliation with them.

[Mel Fulks]

I would , and often do, Google arbors ,summer houses ,and gazebos. Some wonderful creative stuff was done before the BORGS made everything easy.

[roger wiegand]

I haven't looked it up, but I doubt you can span 14 ft with 2x6 rafters. With three posts and a 10 ft span probably a triple 2x12 will work, but there are nice sites and calculators on the web that will figure this out for you. Your biggest problem, as others have pointed out, will be foundation. I'd guess you'll need something ~30" in diameter at the bottom of each hole, dug below the frostline. You cannot just build on top of the existing slab. This will vary with your local soil conditions.

[William Shelley]

I haven't looked it up, but I doubt you can span 14 ft with 2x6 rafters. With three posts and a 10 ft span probably a triple 2x12 will work, but there are nice sites and calculators on the web that will figure this out for you. Your biggest problem, as others have pointed out, will be foundation. I'd guess you'll need something ~30" in diameter at the bottom of each hole, dug below the frostline. You cannot just build on top of the existing slab. This will vary with your local soil conditions.

Warning: Anecdotal evidence incoming.

I have a 14 x 28 covered patio attached to the back of my house. I'm in the process of constructing walls around it in to make a new shop, reusing the existing slab and roof. This roof is made of 15ft 2x6's, 16" OC, and has a 2/12 pitch. There is 2x6 blocking at the halfway mark, where the sheathing joint lands. The roof survived 12+ inches of snow this winter, sitting on top of three layers of asphalt comp, and had 3/8" plywood sheathing under that. I tore all the asphalt off a few weeks ago and I've been repairing rotted sheathing, getting ready to throw down #30 felt with metal roofing panels over that.

I will say this: with 3 layers of asphalt, the roof was pretty bouncy and not in a good way. The rafters developed a substantial sag over their lifetime. If I were rebuilding this from scratch, I would choose 2x8 rafters simply for peace of mind. But 2x6's held up fine in my situation. I expect that removing the layers of asphalt shingles will extend their lifespan as well, by getting all that dead load off.

[David Gutierrez]

all of the joist, beam and rafters sizes are to small for the spans. you should have a real foundation under each post. beams should not go along the sides of the post, the beam should sit on top of the post. there are specific code requirements for attaching the ledger to the house. this has been a common failure point. a good carpenter can be a huge help. also check out the fine home building web site many good practices can be found there.
hard to help you with out knowing more about the area of the country you are in. frost and snow influence the design.

[Bill Dufour]

Our friends in Truckee California looked into this, she is an Architect, She said her county is around 216 pounds per square foot. So the figure of 60/sqaure foot is not for mountains that get deep snow. She got about 30' this season the snowbank out the front walk has settled down to 12'.
Note this does not include any extra sliding off the roof. Short overhangs and/or no shoveling of the perimeter can lead to walls/windows caving inwards.
Bill D.