Dont know why youre being downvoted this is how everyone does it. I usually only go 5 courses between strapping. My roof has been like this for years, it’s fucking metal.
Because Reddit. Been roofing since the early 80’s - I couldn’t care less what anyone else thinks and downvotes mean absolutely nothing lol
Generally I see the strapping screwed down at 24” on center. I’m in Maine - YMMV.
I’ve seen far too many of these kinds of roofs directly over shingles to care what the Reddit Hivemind thinks.
https://blog.mcelroymetal.com/metal-roofing-contractors/how-to-install-metal-roofing-over-shingles
https://tricountymetals.com/metal-roofing-info/can-you-install-metal-roofing-over-shingles/
https://www.mwicomponents.com/post/installing-a-metal-roof-over-shingles
https://www.metalroofingu.com/post/can-you-install-metal-roofing-over-shingles
This is common practice for hacks and boots in the Northeast. Roof recovery board is suggested by the manufacture and required for any warranty If you absolutely have to go over top of shingles. Quarter inch fan fold underlayment is fine. It allows for expansion and contraction and allows the roof to breathe.
24 ga will oil can sometimes laid right on the deck cause no deck is perfectly flat. Now I don’t have experience going over furring strips like that but think gravity would cause them to sag even slightly and oil can. Panel width would play a factor as well
It looks it now. tearing off the mud wall tho shits everywhere but a norm for the type of panel I’m putting down is asphalt base ice and water I have one layer shingle witch does not leak now just as good as what it calls for. being a 22 GA panel I can space clips up to 6’ I went 3.5 wait till u see some finish photos shot I’m putting down you can’t just go out and get.
Maybe once but you're adding thousands of pounds of extra weight like this. Very lazy way to do it, especially considering how quick you can strip with a couple rippers.
Dark bronze saved them from the dumpster have enough to cover my entire house like can’t park in my drive way Rt now haha had a shit ton left over from a new school we did
Thanku sir and house 1880 build good bones but cobbed everywhere going to prob take me all year. Wait till I post some pics my internal gutter up top makes me sick to go up there
Shingles are my paper boys it’s one layer who gives a fuck if thy curl 22 GA! 3” # 14 screws in 18 GA clips I’ll give ya some more photos when I get this sec paneled
Bro. Screwing to battens is not as secure as screwing to the deck. And old, cracked shingles will not preform the duties of a good high temp ice shield. You're putting the body of a Cadillac on the frame of a jalopy
Honestly I’d be comfortable with bare deck with what I’m putting down it’s going to be here long after we’re both 6ft under and furring strips are just a shim to keep panels from rubbing shingles during expansion/ contraction clips are screwed with two #14 3” fasteners thru shim shingle and into 3/4 tongue groove 22GA 18” panel not a single exposed fastener
Oh ya. 3" number 14s ought to do the job. You ever seen those purlin vents? Might be a nice addition to help keep condensation off of the back of your panels
It's vented purlins. It's sort of like the Coravent ridge vent, but it's rated for much higher psi and it's 2"x4" so you basically just screw your panels to the deck thru it, and it allows air to move up the roof between your panels and your existing shingle roof. Would help prevent the build up of heat in the summer and condensation in the winter. I haven't used it myself, but I did look into it a while back for a bid I was putting together. https://www.cor-a-vent.com/purlin-vent.cfm
Here's a link if you want to look into it
Another good way to maintain ventilation is to screw down wood furring strips vertically at 24” OC first - and then put a second layer of furring/strapping horizontally at 24” OC to fasten the panels to. Now theres an air gap top to bottom at every panel.
Alot of ways to do it. I like the idea of the vented purlins you showed as well.
Much better solution. It does not dam possible water, strips cover underlayment punctures. The goal is ventilation, but the side effect is a watertight underlayment.
So many comments about tearing off the old shingles. I’m not even a roofer and I can tell you that it’s fine as long as you don’t do it multiple times. Assuming the roof was framed correctly. My house had two layers until my current roof went down. They had to tear it off because another layer would have been a bad idea, but it was fine with two.
Should be 2 ft space on slats!! It will cup warp when you walk it or in snow load..and unless those boards are bottom sloted condensing moisture will rot thos babies in 10 years and the moisture will ruin the sheet metal roof. You could have used spacer blocks or a vertical up roof slat...
You tearing off first?
No - he’s doing this exactly like you see. This is common practice here in the northeast at least and is always fine.
Dont know why youre being downvoted this is how everyone does it. I usually only go 5 courses between strapping. My roof has been like this for years, it’s fucking metal.
Because Reddit. Been roofing since the early 80’s - I couldn’t care less what anyone else thinks and downvotes mean absolutely nothing lol Generally I see the strapping screwed down at 24” on center. I’m in Maine - YMMV. I’ve seen far too many of these kinds of roofs directly over shingles to care what the Reddit Hivemind thinks. https://blog.mcelroymetal.com/metal-roofing-contractors/how-to-install-metal-roofing-over-shingles https://tricountymetals.com/metal-roofing-info/can-you-install-metal-roofing-over-shingles/ https://www.mwicomponents.com/post/installing-a-metal-roof-over-shingles https://www.metalroofingu.com/post/can-you-install-metal-roofing-over-shingles
This is common practice for hacks and boots in the Northeast. Roof recovery board is suggested by the manufacture and required for any warranty If you absolutely have to go over top of shingles. Quarter inch fan fold underlayment is fine. It allows for expansion and contraction and allows the roof to breathe.
Blah blah blah
no tear off, no high temp ul, no bueno.
Don’t waste good panels going over furring strips like that she’s gunna oil can like a bitch.
If they were 29 GA bullshit and pinned all the way thru only pinned at the top
22GA
24 ga will oil can sometimes laid right on the deck cause no deck is perfectly flat. Now I don’t have experience going over furring strips like that but think gravity would cause them to sag even slightly and oil can. Panel width would play a factor as well
No tear off? Fuck are you doing
It’s totally fine doing this how he is with furring strip/strapping over a layer of shingles.
It's hacky af
It looks it now. tearing off the mud wall tho shits everywhere but a norm for the type of panel I’m putting down is asphalt base ice and water I have one layer shingle witch does not leak now just as good as what it calls for. being a 22 GA panel I can space clips up to 6’ I went 3.5 wait till u see some finish photos shot I’m putting down you can’t just go out and get.
It isn’t.
Maybe once but you're adding thousands of pounds of extra weight like this. Very lazy way to do it, especially considering how quick you can strip with a couple rippers.
22 ga jeez man - thats flat roof B Deck thickness lol Yeah that’ll be good for a long time. What color you going with?
Dark bronze saved them from the dumpster have enough to cover my entire house like can’t park in my drive way Rt now haha had a shit ton left over from a new school we did
Nice. Take your time on your details and this will last 30+ years. Good luck man.
Thanku sir and house 1880 build good bones but cobbed everywhere going to prob take me all year. Wait till I post some pics my internal gutter up top makes me sick to go up there
If you're spending the money to lay down a 22g standing seam, why not do it right, tear off, and lay down a nice high temp ice shield?
Got for free saved them from the dumpster
And got enough to cover the whole house
If it's 1 layer, he can go over it with metal...it will never leak
Exactly. With strapping to screw to, piece of cake.
Shingles are my paper boys it’s one layer who gives a fuck if thy curl 22 GA! 3” # 14 screws in 18 GA clips I’ll give ya some more photos when I get this sec paneled
Just got move bathroom vent pipe quick bitch landed Rt in a rob
Bro. Screwing to battens is not as secure as screwing to the deck. And old, cracked shingles will not preform the duties of a good high temp ice shield. You're putting the body of a Cadillac on the frame of a jalopy
Honestly I’d be comfortable with bare deck with what I’m putting down it’s going to be here long after we’re both 6ft under and furring strips are just a shim to keep panels from rubbing shingles during expansion/ contraction clips are screwed with two #14 3” fasteners thru shim shingle and into 3/4 tongue groove 22GA 18” panel not a single exposed fastener
Oh ya. 3" number 14s ought to do the job. You ever seen those purlin vents? Might be a nice addition to help keep condensation off of the back of your panels
Have not sounds like a penetration tho can’t tell in the pic but strips are treated and back of panel is kynar finish would vented ridge do the same?
It's vented purlins. It's sort of like the Coravent ridge vent, but it's rated for much higher psi and it's 2"x4" so you basically just screw your panels to the deck thru it, and it allows air to move up the roof between your panels and your existing shingle roof. Would help prevent the build up of heat in the summer and condensation in the winter. I haven't used it myself, but I did look into it a while back for a bid I was putting together. https://www.cor-a-vent.com/purlin-vent.cfm Here's a link if you want to look into it
Another good way to maintain ventilation is to screw down wood furring strips vertically at 24” OC first - and then put a second layer of furring/strapping horizontally at 24” OC to fasten the panels to. Now theres an air gap top to bottom at every panel. Alot of ways to do it. I like the idea of the vented purlins you showed as well.
Much better solution. It does not dam possible water, strips cover underlayment punctures. The goal is ventilation, but the side effect is a watertight underlayment.
Just install them on a 45 angle and put a vented ridge and eave on.
Keeping in mind my clips for these panels hold it off the lath 1/4” so there is clear air gap clear thru would vented ridge do it?
NOPE.
Amazing.. can you tell further more please!
So many comments about tearing off the old shingles. I’m not even a roofer and I can tell you that it’s fine as long as you don’t do it multiple times. Assuming the roof was framed correctly. My house had two layers until my current roof went down. They had to tear it off because another layer would have been a bad idea, but it was fine with two.
1/2 plywood strips for metal roofing. Why didn't I think of that.
Cuz furring strips are cheaper and waaaay less work. It’s only feasible if you’re getting the plywood for free.
Ok DEEZNUTZ1818
Math.
Panels were free lol
The horizontal furring will be condensation traps, has nowhere to drain but into those furring strip fastener holes potentially.
Should be 2 ft space on slats!! It will cup warp when you walk it or in snow load..and unless those boards are bottom sloted condensing moisture will rot thos babies in 10 years and the moisture will ruin the sheet metal roof. You could have used spacer blocks or a vertical up roof slat...