Where to screw down 5V roofing

[MillWeld]

I didn't want to hijack a nearby thread to digress on this topic so I started a new one.
When I built my barn in 1985 I nailed the 5V roofing thru the top of the V with roofing nails with pre-mounted rubber washers. My brother-in-law just had is home re-roofed with 5V and the installer put the fasteners (don't remember if they were nails or screws) in the flat part. I was appalled and told him it I have never seen that and watch for leaks. I built a small trailer shed a few months ago and decided to Google installation of 5V roofing. The advice from manufacturers was to screw it in the flat part! What has changed? The fact we use screws now which will not work their way out? are the screw seals better now? So I screwed down the roofing on my shed in the flat. Sure was a lot easier. BTW the shed on the barn has developed one leak at a nail on which I dabbed some tar.
Bob

 

[MotorSeven]

Ha, I just had a comment in that other post about this. I am just guessing but, yes I think it was when the fastener changed from nail to screw. I have replaced the tin on a lot of old barns here nailed thru the rib. I have seen a lot of them with nails sticking up from the rib and the lead or neoprene washer not even touching the metal. I also see a ton of damaged ribs, crushed by hammer or screw. The local tinman here says screw every flat, not the ribs & that is what I have been doing for 10 years or so. I have helped put on 5 or 6 roofs here and done 3 of my own in 4+ years. No leaks.

 

[DJ54]

I just had a new shop, and horsebarn built. The contractor himself did not show up the day the roof was being put on, until about noon. The self appointed foreman/lumber salesman instructed the workers to pre-drill in the flats. I prefer in the ribs... The rest of the roofing WAS put in the ribs...

I can't help but thinking 10 years down the road, when possibly one of those neoprene washers loses it's seailng properties, that put into the flats will allow a lot more water, to possibly seep in. The closer to the bottom, the more water... On top of the rib, lots less water running by, and most should shed off.

In 1988, my Dad built a carport, and put screws in the ribs. No leaks to this day. I also put a new 36' X 64' horsebarn up myself, in '00, with screws in the ribs, and no leaks either.

I guess maybe a lot has to do with taking your time, and if a rubber on the screw squishes out, is over torqued, etc., take it out, and replace, not just go on to the next...

I can live with my decision to put them in the rib... JMHO....

 

[ustmd]

I am wirth MotorSeven. We always screw on the flat, not on the ribs.

 

[tommu56]

I wont get in to the fight valley verses ridge.

But follow the manufacture's specifications is my suggestions.:thumbsup:
I know they have dealt with more roofs than all of us on here combined.:laughing:

mine is Wheeling




tom

 

[2manyrocks]

I have a barn built in the 1930's that is nailed with lead washers in the rib. in those days, the metal was thick enough that you could hammer it pretty hard. Although the nails are starting to withdraw due to expansion and contraction over the years, the lead washers are still holding up.

I recently had a 29 gauge roof installed, and the manufacturer's recommendation was to put screws on either side of the rib that overlaps, and one screw in the flat besides the other ribs. The installer fussed and fussed that they should go in the middle of the flats between ribs because they were less noticeable and that a screw should go in the top of the overlapping rib. Then he said the manufacturer was wrong and the overlapping rib portion would curl and start to leak in a few years.

So who to believe? I told him to do it per the manufacturer's recommendation.

I forget who said it here before, but I think the reason you don't screw in the ribs of the thinner metal is that the metal is so thin that it can create a dimple. Plus, the profile of many ribs is not a V anymore and maybe not quite the strength of the V profile.

If you happen to have heavy gauge V roofing, looks to me you'd go through the rib. If it's light gauge, probably stuck with going through the flats.

 

[BeezFun]

But follow the manufacture's specifications is my suggestions.:thumbsup:
I know they have dealt with more roofs than all of us on here

I agree, follow manufacturer's instructions, if for no other reason than hoping they'll cover a warranty claim if there is one. There was a detailed drawing in the bag of screws I got with my last ribbed roof purchase. It called for screws in the flat right next to the rib for new installations, and screws in the rib if installed over some kind of existing roof like shingles. Had a detailed fastener schedule for all areas like at the rake, overlaps, etc.

On the one roof I installed years ago through the ribs, I found it easy to bow the flat sections by screwing down too tight, had to jiggle around and get just the right tightness. Also didn't feel structurally as solid as going into the flats. Also, even if an oring on the flat fails completely, the roofing is still pressed tightly against the material underneath which will help stop a leak. If an oring on the rib fails, water goes right into an open cavity.

 

[earljr59]

I notice around here the Amish do most of the metal roofs,and screw on the flat areas only.

 

[beppington]

The 5V metal roofing on my parents' house & several barns was professionally installed, & they used screws on the flats in all cases.

I installed my own barn's 5V metal roof about 8 years ago, & not knowing better used the twist nails with soft lead washers on top of the ribs: Those nails work their way back out; The lead seems to deteriorate & shrink & loosen; And even when being very careful not to over-hammer the nails in, in order to get a tight seal around the lead washer it causes the flats of the metal to kind of raise up a little.

My next metal barn roof will definitely have the flats screwed down :thumbsup:

Oh, also, I just had our 20-year-old home inspected (for insurance reasons) & discussed soon replacing my shingle roof with metal; The inspector said metal roofing is great, would prob last the rest of my life, but that what the roofing makers don't tell you is that there are no fasteners that last as long as the roofing, so there's a chance the fasteners will need to be replaced someday.

 

[massey990]

I agree with those that follow the manufacturer's guidelines, however, a hole with no screw or nail on the top of the rib will rarely if ever leak, a hole in the flat will almost always leak.
Most of the installers I have observed that fasten through the ribs pre-drill the panels.