[Roofmaster417]

Well as ironic as it is I am on a project that has plywood installed horizontal when it is going to function more appropriate installed vertical.I know,,I was yakking and trying to prove why plywood should be ran horizontally instead of vertical.

The rafters run vertical for 8' then run into a header after that they (Rafters) are horizontal.The rafters run 24" O.C and the plywood that was installed horizontal on the rafters buckled and created a back wash area causing leaking and total saturation of the decking.

The project is a 440 square 1 layer hotel.So I am replacing every sheet of plywood that is buckled.The project started today and 24sq. Was removed and all plywood was removed and installed vertical with H-clips on the seams.

I will post pix tomorrow but just wanted to say I was wrong and learned a very valuable lesson.,.,Basically know my facts before putting my 2 cents in.So there you have it,,,I was wrong about installing plywood vertical. :thumbsup:

 

[Roofmaster417]

Well as ironic as it is I am on a project that has plywood installed horizontal when it is going to function more appropriate installed vertical.I know,,I was yakking and trying to prove why plywood should be ran horizontally instead of vertical.

The rafters run vertical for 8' then run into a header after that they (Rafters) are horizontal.The rafters run 24" O.C and the plywood that was installed horizontal on the rafters buckled and created a back wash area causing leaking and total saturation of the decking.

The project is a 440 square 1 layer hotel.So I am replacing every sheet of plywood that is buckled.The project started today and 24sq. Was removed and all plywood was removed and installed vertical with H-clips on the seams.

I will post pix tomorrow but just wanted to say I was wrong and learned a very valuable lesson.,.,Basically know my facts before putting my 2 cents in.So there you have it,,,I was wrong about installing plywood vertical. :thumbsup:

Also since the rafters run into the walls of each unit (2 hotel rooms per section) the span is about 28' per section width and 30' for height per section we will be bracing the span for snow load.I feel it might make a difference in weight factors with the plywood being ran vertical ? Is it safe to assume this ?

Also a couple sections of (H) rafters were so moldy and saturated they were pulled and replaced with new hangers and rafters ran vertical.

When installing plywood vertical versus horizontal should I brace as usual or ?

The existing bracing is a block (Rafter to Rafter) style.But the rafters are not braced to the walls or ceiling joist.They are free hanging the entire width.

 

[rossfingal]

Without pictures -

I'd probably throw some bracing/blocking in -
including some 45 degree blocking/bracing.

"RF"

 

[Canucker]

Well as ironic as it is I am on a project that has plywood installed horizontal when it is going to function more appropriate installed vertical.I know,,I was yakking and trying to prove why plywood should be ran horizontally instead of vertical.

The rafters run vertical for 8' then run into a header after that they (Rafters) are horizontal.The rafters run 24" O.C and the plywood that was installed horizontal on the rafters buckled and created a back wash area causing leaking and total saturation of the decking.

The project is a 440 square 1 layer hotel.So I am replacing every sheet of plywood that is buckled.The project started today and 24sq. Was removed and all plywood was removed and installed vertical with H-clips on the seams.

I will post pix tomorrow but just wanted to say I was wrong and learned a very valuable lesson.,.,Basically know my facts before putting my 2 cents in.So there you have it,,,I was wrong about installing plywood vertical. :thumbsup:

At least you're smart enough to recognize when a different application is required, you know "why" it's done. You're miles ahead of a lot of people. I'm not a roofer but where I work, I always try to explain the reasoning for why we do it a certain way. A lot of times there is a variation on a problem that needs to be solved, so the more you know why, the more flexible you can be in problem solving and still not kill anyone or damage the equipment. Good for you:thumbup: (Now if only I could find more contractors like you, and less of the ones that learned everything they needed to know in 1973.haha)

 

[jagans]

You aren't wrong. Plywood is supposed to run with the face grain perpendicular to the supports. Supports that run horizontal are Called Purlins. As far as plywood goes, you better buy American Made APA stamped material, otherwise you might be back out on this project tearing it off. The crap they sell in the BigBox stores is absolute garbage. I would also recommend Fir. Much more stable than WP.

 

[wrongdave]

That had to give you a chuckle when you realized what you were about to do. And just weeks after that other thread.
That's why I try to avoid absolutes. There are almost always exceptions.

 

[joecaption]

Think that's bad I was driving by a job site and saw what I though was going to be a disaster about to happen.
A local contractor for some reason was trying to lay felt vertical on a 12 12 pitched roof, everything was fine until he got to the peak, instead of making a cut which still would have been done wrong, he went over the peak and just let it roll down the roof.
It came flying down and knocked the guy right off the walk board onto the ground.

 

[jagans]

There is a good lesson regarding things like this in the book "Yeager" Its obviously about Chuck Yeager the Famous Pilot.

Three test pilots died during the trials of the F-86 Sabre Jet because of one bone head on the assembly line that insisted on doing things his way, even though "His Way" was in direct contradiction to the plans.

 

[jagans]

Wow, what a concept, Joe. Bowling for roofers!

Side bar. I was at a metal roofing convention talking to a guy I knew about one of his latest projects. He was on a copper SS metal roof, checking it out, when the rope he was tied off with came loose. I said Holy crap, how bad was the fall? He said he really wasen't really worried too much about the fall, because there was a lower roof down about 10 feet, but those damn snow birds really had him shook up!

 

[joecaption]

Ouch, that hurts just thinking about it.
I watched a guy slide off of a three story slate roof at a school one day, talk about lucky there was a man lift at the edge of the roof and he landed right on the platform, he hit, stood up, and pasted out when he looked down.
A few feet ether way and he would have hit the ground instead.
He had to go home and change his soiled pants.

 

[PatChap]

Ouch, that hurts just thinking about it.
I watched a guy slide off of a three story slate roof at a school one day, talk about lucky there was a man lift at the edge of the roof and he landed right on the platform, he hit, stood up, and pasted out when he looked down.
A few feet ether way and he would have hit the ground instead.
He had to go home and change his soiled pants.

I seen a crew stripping the slates off an old church this past fall, they had a flat roof at the peak for staging the material, etc. To strip one section about 5sq, one guy slid down from the flat roof onto a plumbing vent in the middle of the roof. A solid 10-15ft down from the peak, 3 stories up on a 12/12 or better. I quit watching once I'd seen that.

 

[joecaption]

That would leave a mark.

 

[Roofmaster417]

That had to give you a chuckle when you realized what you were about to do. And just weeks after that other thread.
That's why I try to avoid absolutes. There are almost always exceptions.

Yes,,,I laughed very hard once I went by the job after the roof was off.I have some pix but it has been so cold here I am chilled to the bone kickin back with my tablet,feet up,a cold beer to the right,remote to the left,60"L.E.D to the front and phone in my truck.The project is going really well the roof is much more solid with the plywood vertical.

Will post pix tomorrow afternoon.Years ago I seen a laborer loading a roof and he lost control of a bundle and it slid down the roof and wiped out another laborer an the lower level.It was no joking matter because he broke his neck and died about a week later.He was a good guy.A hard hat would had done nothing for him.

 

[OldNBroken]

Roofmaster, I refrained from getting involved in that thread and try to convey that there are exceptions to every rule. It's funny how coincidental that was huh. :thumbsup:

Nice to see you see the humor in it all too. Anyways, we all learn something new still. Well, by we I mean all you other guys because I'm pretty sure I still know everything already so :whistling2: :whistling2: :whistling2:

Well, have a great day everyone. :thumbup:

 

[paulsmith544]

Well as ironic as it is I am on a project that has plywood installed horizontal when it is going to function more appropriate installed vertical.I know,,I was yakking and trying to prove why plywood should be ran horizontally instead of vertical.

The rafters run vertical for 8' then run into a header after that they (Rafters) are horizontal.The rafters run 24" O.C and the plywood that was installed horizontal on the rafters buckled and created a back wash area causing leaking and total saturation of the decking.

The project is a 440 square 1 layer hotel.So I am replacing every sheet of plywood that is buckled.The project started today and 24sq. Was removed and all plywood was removed and installed vertical with H-clips on the seams.

I will post pix tomorrow but just wanted to say I was wrong and learned a very valuable lesson.,.,Basically know my facts before putting my 2 cents in.So there you have it,,,I was wrong about installing plywood vertical. :thumbsup:

nice work there, as every one say nothing is impossible, if your will power is strong..