Single Slope Carport

[bacaruda]

I need to add one to my garage for the pontoon. It's an odd size 25x11. Where can I see design guidelines? Center to center for rafters? Etc.

Thanks,
Jim

 

[camarotoolman]

2x6x12s, 16oc should be fine.

 

[nmk_61802]

2x6x12s, 16oc should be fine.

Making some leaps on the design, I get the 2x6's as being on the light side at 16" OC for 11'-0" with a shallow 4/12 (common on lean to structures) slope. Figuring roof loading at 20PSF Live & 15 PSF dead with no ceiling, I show Southern Yellow pine as capable of 10-3 max. Change the spacing to 12" OC and they barely pass, move up to 2X8's at 16" OC anything greater than #2 passes.

To really answer any design questions, location including State (This is needed for local Snow load information) needs to be supplied. Should also provide some additional information such as planned method of construction, roof type, slope or any basic details you can provide.

Also if you have a local Building or Code enforcement agency they may be a good reference to help answer some basic (or minimum requirment) questions.

 

[bacaruda]

Making some leaps on the design, I get the 2x6's as being on the light side at 16" OC for 11'-0" with a shallow 4/12 (common on lean to structures) slope. Figuring roof loading at 20PSF Live & 15 PSF dead with no ceiling, I show Southern Yellow pine as capable of 10-3 max. Change the spacing to 12" OC and they barely pass, move up to 2X8's at 16" OC anything greater than #2 passes.

To really answer any design questions, location including State (This is needed for local Snow load information) needs to be supplied. Should also provide some additional information such as planned method of construction, roof type, slope or any basic details you can provide.

Also if you have a local Building or Code enforcement agency they may be a good reference to help answer some basic (or minimum requirment) questions.

OK, pitch will be more like 2/12, Area is WV panhandle, zip 25404. Not far from DC. Not in big mountains, Shenandoah Valley. Method of construction?
4x4's, outside inside 2x8 boards on posts, 7/16 sheathing, standard shingles,
I'd hoped to do 2x6 rafter boards, 12" OC ok. Oh, 2x8 nailed to current structure on stud.
Post spacing?

Thanks,

 

[D KRAGER]

Been there done this. For a pontoon boat and all. I have pole barn construction. I went with 2x8's on 24" centers, I have around a 2/12 pitch on it. I used 6 x 6's for my posts on the outside.

 

[bacaruda]

Thanks, please see topic. I have garage I'm putting this on the side.

 

[nmk_61802]

Making some leaps on the design, I get the 2x6's as being on the light side at 16" OC for 11'-0" with a shallow 4/12 (common on lean to structures) slope. Figuring roof loading at 20PSF Live & 15 PSF dead with no ceiling, I show Southern Yellow pine as capable of 10-3 max. Change the spacing to 12" OC and they barely pass, move up to 2X8's at 16" OC anything greater than #2 passes.

To really answer any design questions, location including State (This is needed for local Snow load information) needs to be supplied. Should also provide some additional information such as planned method of construction, roof type, slope or any basic details you can provide.

Also if you have a local Building or Code enforcement agency they may be a good reference to help answer some basic (or minimum requirment) questions.

I still stand by the 2x8 @16 OC recommendation (should be cheaper and stronger than 2X6 @ 12 OC), the 2/12 slope is actually worse, snow load for your area should be 20PSF and my original number figured it with a shingled roof (not the lighter metal). I would use a round number for post spacing say 25'-0"/4 or 5 posts 6'-3".

 

[D KRAGER]

Thanks, please see topic. I have garage I'm putting this on the side.

Sorry for trying to help you out. Just because it's a pole building doesn't make it that much different. Thought that rafter spacing might help you out.

 

[csp]

Thanks, please see topic. I have garage I'm putting this on the side.

It doesn't matter if you're putting it on the side of a garage, a barn, or a skyscraper. The framing design will be the same for any of them for what you asked about.

D KRAGER gave you good, usable information.

 

[nmk_61802]

It doesn't matter if you're putting it on the side of a garage, a barn, or a skyscraper. The framing design will be the same for any of them for what you asked about.

D KRAGER gave you good, usable information.

Correct to an extent. Basic construction is similar, Sheating, siding and topping material is the difference.

I asked about basic materials of construction because framing must hold the weight of the topping material. Roof framing cares a great deal if you are topping them with metal (light), shingles/ shakes (medium) or tile/ slate (heavy).

 

[bacaruda]

I still stand by the 2x8 @16 OC recommendation (should be cheaper and stronger than 2X6 @ 12 OC), the 2/12 slope is actually worse, snow load for your area should be 20PSF and my original number figured it with a shingled roof (not the lighter metal). I would use a round number for post spacing say 25'-0"/4 or 5 posts 6'-3".

Thanks, and to all you other guys, thank you also. Scope of project varies greatly from yours.

I talked Fri. to county engineer, and he said 2x6 16oc was code. Even for 2/12. Also 2x8 in and out for header was good for 6' post seperation. He also said shingles could not be used less than 3/12. Metal or "roof roll".

Further comments? I'm not trying to low ball cheap, but to many of us, cost is a concern.

 

[csp]

Correct to an extent. Basic construction is similar, Sheating, siding and topping material is the difference.

I asked about basic materials of construction because framing must hold the weight of the topping material. Roof framing cares a great deal if you are topping them with metal (light), shingles/ shakes (medium) or tile/ slate (heavy).

Well no kidding. Snow loads, wind loading, etc. all will change the specifics of every design.

I talked Fri. to county engineer, and he said 2x6 16oc was code. Even for 2/12. Also 2x8 in and out for header was good for 6' post seperation. He also said shingles could not be used less than 3/12. Metal or "roof roll".

Further comments? I'm not trying to low ball cheap, but to many of us, cost is a concern.

Your engineers specs match what I've run into when building. I built a loafing shed with a 2/12 pitch and built with 2x6 on 24" centers, but my span was only 8'. My post separation was 8' and I used a doubled up 2x8 header. He's correct about no shingles on less than 3/12 pitch. That's pretty common knowledge, especially if there's any snow to be had.