Metal roof installation advice

[khd]

Interestingly enough, I found this:http://www.idealroofing.com/PDF/AMC_UL_ENGLISH.pdf
Which clearly shows fastening through the flat for a UL rating. All of their old literature showed fastening through the rib. Maybe they are joining the other manufacturers in the proper method.

shvl73:

After you pointed it out now I do see what you mean as far as being able to hold the panels to the roof. I chose to do 2x4 purlins 16" OC so I won't have to worry about being able to support the roof. With a twelve pitch roof I don't think I will have to worry about leaks through the screws if this should be a concern over time with fastening on the flats of the panels.

Thanks,
Kevin

 

[tallyho8]

shvl73:

After you pointed it out now I do see what you mean as far as being able to hold the panels to the roof. I chose to do 2x4 purlins 16" OC so I won't have to worry about being able to support the roof. With a twelve pitch roof I don't think I will have to worry about leaks through the screws if this should be a concern over time with fastening on the flats of the panels.

Thanks,
Kevin

That looks like a very sturdy, well constructed building!

 

[shvl73]

khd,
Your tractor barn will be far nicer than my house! Looks great!

 

[TwinWillows]

We used metal from Paramont Metal for our 40 x 48 horse barn. The manufacture had installation drawings for fastening the panels. I followed them. It was screws thru the flats & nails thru the ribs. We used screws w/rubber gaskets & put them thru the flats. The caution not to overtighten the fasteners was noted by the manufacturer. We tried not to but I'm sure some are "flatter" than they should be... I looked @ many barns in our area before building ours. All that used screws were thru the flats & nails thru the ribs. To do otherwise might be a regional or manufacturer difference. It'd probably be best to see what the installaion instructions are for your materials.

 

[Roto]

I cant believe that ideal says you can use 7/16inch OSb for the plywood and i was worrying about 3/4" OSB. That last link had the specs.

mike

 

[tallyho8]

I cant believe that ideal says you can use 7/16inch OSb for the plywood and i was worrying about 3/4" OSB. That last link had the specs.
mike

Yes, but if I read it correctly, using the 7/16 osb you must have joists a minumum of 24"oc and the screws must be 12"oc which means using 54 screws for one 8 foot panel. This gives it 54 chances to leak on each 8' panel. I would prefer to use thicker deck or strapping with less screws. And don't forget the underlayment!

 

[shvl73]

7/16" osb doesn't seem like a good idea to me either. I would think it wouldn't hold the screws well at all.

 

[Roto]

I agree that 7/16 is out of the question but the fact they mention it means my 3/4"OSB idea should work fine. I still think after reading this im going with shingles i still have to decide what plywood. I wonder about 7/16" with asphalt shingles? Its $4.88 a sheet right now!!

Mike

 

[shvl73]

7/16" osb won't hold nails well either. I had a house (about 10 yr old) with 7/16" osb exterior wall and vinyl siding, during a little remodel project I discovered the nails could be pulled out with my fingers. Now, I realize siding nails are not driven tight but, they're not under stress either. I can't think of what caused them to be so easily removed other than the osb didn't have adequate nail retention.

 

[mrutkaus]

I used 26ga 5V for an outbuilding roof 20 yrs ago; nails with washers on the peaks, no leaks!

In a recent adventure I put down 29ga 5V with no nails or screws, just lots of 50yr urethane to the solid sheathing underneath. It's not going to go anywhere. If you don't believe it, get some good quality 50 yr urethane caulk and glue anything together, let it set for a week, then try to take it apart!

It also works great for glueing windshield antennas to glass, but it takes days to set.

Mike