Can you put metal over 3 layers in ohio? --74.141.xx.xx

Two layers of asphalt shingles is the limit --50.4.xxx.x

The first house I bought a metal roof for had 3 layers of worn-out shingles on it. Removing 3 layers would have been costly. 5 years ago, a metal roof was laid on top of it and since then I have had no problems. --68.63.xxx.xxx

Not tearing off the existing layer(s) reduces the lifespan of the new layer , that plus the additional uncertainty makes the savings compared to tear off a wash --50.4.xxx.x

Most places require a structural engineer to verify that the roof framing will support adding any more than 2 layers (original + 1 layover) of roofing before allowing it. --96.237.xx.xx

Not worth the risk. Tear it off. --98.122.x.xx

If you get snow let us know. How many were seriously hurt? --99.103.xxx.xxx

Steve, why would any structural engineer in their right mind sign off on something like that? --50.4.xxx.x

Ohio will have a heavy snow load which Roy wont have in AL,no way should you be putting another roof over 3 layers of shingles --72.231.xxx.xxx

I've never heard of one actually doing it. In my 50+ years of being in construction I've only done 2 lay over roofs. One was going to be torn down in 5 years & the other was as a favor for a friend who was suppose to do the job but had a health issue come up. IMO it's always best to strip the old roofing, refasten / replace the boarding, replace vent pipe boots, add base flashing around chimneys & in my area use I&W in valleys, around roof penetrations & at the eaves. --96.237.xx.xx

I had a roof with 3 layers on it and needed replaced. I tore it all off. The weight from the 3 layers did cause damage to the structure over time. Since then, I don't want any more than 1 layer. This comes both from the damage it caused and also the job it was to tear off the 3 layers (I was the one tearing it off, it was in my younger and not so wiser days). --98.175.xxx.xxx

We don't get a lot of snow down here but doesn't snow just slide down off of slick metal roof? My metal roof is so slick, you can't even walk up it without wearing special shoes. --68.63.xxx.xxx

It was the contractor that recommended this. He said no code in Ohio for maximum layers --74.141.xx.xx

You need to point your contractor to BOCA, there it is said that using dimensional shingles is 2 layers there fore when using them every roof job will be a tear off, look at the underside of the roof deck for splitting of the structural members - this is where it gets expensive tearing off the decking so you can sister or replace this wood. --76.188.xxx.xx

I just did a quick Google search of Boca. I found nothing that relates to roofing. But it sounds like bottom line you would not go over three layers with metal? Further conversation with contractor… 20 pounds per one square for metal versus 100 pounds per square of shingles. He is still highly confident that it is safe to do that. His further conversation is that snow is not going to stay on metal. Snow would slide right off. Furthermore he said it is a six pitch roof. According to him he said that’s somewhat steep --74.141.xx.xx

up.codes/viewer/ohio/ibc-2015/chapter/16/structural-design#1608 --76.188.xxx.xx

Thank you --74.141.xx.xx

VEE You have lead them to water but they won't drink!!!! --99.103.xxx.xxx

VEE You have lead them to water but they won't drink!!!! --99.103.xxx.xxx

Any roofer who told me that 3 layers plus a metal roof was ok I would question his knowledge of anything else related to the job --72.231.xxx.xxx

SO the judge ordered that when the cost of materials comes back to a normal rate, at that time my circumstance should be reevaluated. I won. --47.156.xx.xx

SO the judge ordered that when the cost of materials comes back to a normal rate, at that time my circumstance should be reevaluated. I won. --47.156.xx.xx

I live in North Idaho. We have lots of metal roofs and lots of snow. Snow does not slide off of metal roofs (unless it is a very steep roof -- think A frame cabins) WHILE IT IS SNOWING. The snow does avalanche off the roof once the storm has passed and the weather warms slightly. Be sure to have snow brakes installed over doorways unless you have covered porches. --98.146.xxx.xxx

Run away from that roofer, he doesn't have any idea what he is doing. --96.235.xx.xx

--99.59.x.xxx

In my experience, it's cheaper in the end to just do it right. So NO! --71.210.xx.xxx

Get a second opinion from a comment metal roof installer. --174.229.xx.xxx

Thank you to all. Doing a complete tear off --74.141.xx.xx

The lad in Bridgeport was right..”There is a sucker born every minute”................. Charlie.......................,,,,,,,,,,,,,,,,,every one minute! Or is that,every second..........,,,,,,,........,,, ,,,,,,,,,,,, ............ --32.214.xxx.xx

for pitched roofs with asphalt comp i spec full tearoff and rehab of all carpentry, UDL underlayment, GAF elk lifetime shingles, all new metals and ohagins vents as needed. for the flat roofs i spec a 2 ply dibiten torchdown with all new metals. i AM considering going to a one ply dibiten and going to a silicone coating at 7-8 years. the GE scm3502 can be rolled right over a clean surface w/o primer. i have used the GACO silicone with good results as well and like that it goes on FAST and is SPECIFICALLY RATED FOR PONDING WATER...something we see on lots of flat roofs --76.176.xxx.xxx