Adding a lean-to

[Molerj]

I would like to add a lean to on my pole barn. The pole barn has metal siding. I would like to add on 16'X30'. I will be buying 16' steel sheets for the roof. What would be a sufficient drop on the roof level? From the bottom of the eaves on the edge of the building is 10'6". I was hoping to keep the height of the lean to 8' on the lowest end. Would two foot drop on the 16' length be enough? What type of framing 2x6 or 2X8 or are there trusses that I can buy? I was thinking of buying sheating boards to go lengthwise over the framing to screw the roofing to. This is facing the north so there may be a little snow to deal with in the winter. Any suggestions are welcome. I have attached a few pictures where the lean-to will be located.

 

[Molerj]

another picture

 

[Junkman]

Don't know about the snow load in Ohio, but in CT where I live, the building inspector won't allow a structure to have much less than a 4" in 12' pitch. With a 4 in 12 pitch, you would have a 64" difference between the highest point and the lowest point of the roof. I would suggest that you consult with the local building official for the requirements in your area, that is unless you are doing this with out a permit. If that is the case, then inquire of the building department in a town that is 4 or 5 towns away from you. It is one thing to build without a permit, but another not to build it to code.

 

[Soundguy]

Another thing to consider, is that in many areas, buildings classified as pole barns are usually exempt from permitting, etc, etc.. if there is no power / water run to them at the time they are built... That isn't to say though to build something unsafe-. If it weren't for his snow load... all he would need is enough drop to shed rain and simple 2x6 construction with some 1x3 or 1x4 purloins for the tin. Figuring for snow, I think he's on the right idea with the 2z6's and the sheeting.. though he needs to keep in mind that he may have a failure during a big snow, and just plan accordingly, and accept any loss of building material/stored items if there is a failure due to snow.
The building materials will probably be a moot point... that project isn't a pocket drainer... what he stores under it may or may not be another story... If it is say... farm implements.. I'm guessing that the worst that would happen is that they would be burried by snow .. but probably intact.. if it is feed/hay... then it may be a loss... etc. He just needs to determine what level of risk is acceptable to him... especailly if he wants the 8' minimum at edgoe of the improvised structure.

Soundguy

 

[cowboydoc]

For 16' I'd definitely go with 2x12's. If you put sheeting on there you will have to go with 2x12's. That's alot of load. 2' drop would be the minimum but with your header you are still not going to be 8', more like 7' max.

 

[Molerj]

Thanks so far. No inspectors, code etc. where I live. I didn't mean to infer that I would be sheating the whole roof. I was thinking of several rows just to screw the sheating to. Maybe 1X3 or 1X4's as suggested would suffice. I guess I can raise the side that would be against the building, but that would reduce the size due to the angle of the eaves from the pole building.

 

[cowboydoc]

Just run purlins. You'll want to put 2x4's on their side. This will give the roof strength.

 

[Soundguy]

</font><font color="blue" class="small">( For 16' I'd definitely go with 2x12's. )</font>
Pretty big stuff.

Around here that isn't even called for in residential construction... Heck.. I don't think I've seen that in flooring.

Must be some heck of a load you are expecting... If he's expecting that much load.. sheeting and/or roof tin ain't gonna cut it.. he'll need timber across that roof.

My -non- snow rated pole barn ( which met codes and had a permit pulled) used 2x6's and 1x4 purloins, and the tin roofing metal. Either 6x6 or 8x8's for the uprights, and 4x4's as intermediate uprights between the interior horse stalls.

Some other misc. lumber sizes were used for non-load portions..like decorative cut soffit/facia, etc, and for stall construction.

I'd second the recomendation that he shorten the run and move higher up on the wall to achive a bit more drop/per/foot.


Soundguy

 

[yooperdave]

I don't think 2x12's sound bad at all.

Tell me exactly where you are located and I will run a snow drift calculation. This would be more prudent than expecting a failure under less than ideal conditions.

Failure should never be considered as an option. Size the rafter for the worse case loading, and live happily ever after.

Send me a private email if you need more help.

Good Luck

Yooper Dave

 

[Phred]

Big difference in the snow loads from Iowa to central florida to say the very least!

Fred