metal over shingles w/out furring strips?

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metal over shingles w/out furring strips?

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I recently had a contractor come out and install a nice metal roof over asphalt shingles. When we signed the contract furring strips were supposed to be put added. No underlayment was installed and the strips were not either. The guy who installed it said that the owner had no idea what he was talking about and it was irrelevant to have the wood attached. After browsing many forums i can see a few different opinions on the matter and just want to know, is it worth going to court over for a breach of contract or is the installer correct and its better that i do not have them? Thank you in advance from a floor guy!
Guest User
2013-11-21 14:36:43.000000
I'm building a tiny house and was planing on 2x6 rafters (cavity filling with insoleshin ) 1/2 osb sheathing, weather watch barrier, then furring striping on top horizontally, then (Classic Rib Steel Roof Panel). Was wondering the best spacing? Or if I should go a different route?
Guest User
2014-08-20 23:46:45.000000
I am installing a metal roof on a single wide trailer it has shingles on it I plan to remove and lay metal on the plywood I have been told I must use 2×4 perlins are they necessary also the roof has a vent that runs the length of the trailer I plan to remove it as well and run the metal over it is that acceptable
Guest User
2014-08-21 23:19:33.000000
Is it ok to screw 29 gauge metal over the top 3 tab shingles with synthetic felt in between
Guest User
2016-09-13 16:16:17.000000
I was told by a contractor that if they put a metal rood over existing shingles that there could be a fine is caught to the property owners. In the the state of PA is this true?
Guest User
2016-09-22 11:13:31.000000
I am looking into getting a metal roof installed over shingles onto my home. 29 Guage is what I've been quoted prices on. One contractor says you are making a mistake if you don't first have the roof stipped with 1x4 and another says it's a waist of money to strip?! My roof is quite steep. I'm confused! Help!
Guest User
2017-05-01 11:37:36.000000
I've got an older double-wide (1987) with no attic or ridge vent. I've had the roof patched after a couple of bad storms. My question is, before I prep for the metal roof, how flat does the roof need to be before I lay down the felt and furring strips. There are several spots on the back side missing shingles. Is it necessary to patch these spots as well, or will the felt and strips be level enough to screw the metal straight to it. Also, is there any way to cut a ridge vent where the halves meet. There is no attic, so i haven't seen a solution to this problem. Would be nice, since in South Carolina it gets hot, and my main living area has vaulted ceilings. Very informative site. Nice Job!
Guest User
2017-05-02 02:59:12.000000
Hello Todd, We had a leak and we had put some tar to stop it but wasn't working so We had a roofer install a metal snap-tite roof on top of our old shingles.Our home is a low slope manufactured 2-12..or 3-12 at best..he didn't put anything on top of the old roof just metal no felt or wood strips..I know this because I watched part of the day. Will our roof be okay?
Guest User
2017-06-07 12:36:28.000000
I want to install a standing seam metal roof but don't know how to adapt the bathroom fan vent to the roof. I can't seem to find a vent cap with a flexible base to screw down to seal to the roof. Any assistance would be appreciated. Thanks.
Guest User
2017-06-09 02:50:13.000000
Unfortunately, the cap that is on the shingle now is just a cap, no protruding pipe and I still don't know how I would extend that through the roof and the solid steel sheet without some fancy custom flashing or such.
Guest User
2017-06-09 11:36:16.000000
I'm looking to install a metal roof over my existing shingles one contractor says I need the wood stripping's the other contractor says it's a waste of money that it can be put directly on top of the shingles. I'm not for sure which would be best
Guest User
2017-08-20 17:45:06.000000
Questions in last paragraph. A little back story precedes: We had a metal roof installed last year (classic rib, exposed fasteners). Contractor initially was going to tear off the single layer of shingles, but then decided not to (later removed this cost from the contract). He did not put underlayment between the old shingles and metal. But that's a different story. The installation was not to our liking. Wrinkles in the metal, ridge caps didn't look straight. No flashing around the brick chimney (on purpose - he said he sealed it up...). Boots missing from vent pipes. Roof panels looked to be cut too short where they overlapped the valley flashing (looked like too much flashing visible - probably water tight, but just looked bad to us). Etc. Contractor stated that the old house framing prevented having nice straight lines. We feel he should have done something about this before he put the metal on. Currently he has sent us a bid to tear off the roofing down to the rafters and install 5/8 OSB, then titanium underlayment, ice/water shield, then metal. I'm assuming he will not attempt to re-use the current metal, but I haven't confirmed this with him yet. Even though he should have corrected any framing issues on the front end (and included in the cost of his bid), we probably will agree to pay the additional to have it corrected as opposed to trying to force him to make it right at no additional cost to us. But it does leave a bad taste in my mouth. My questions are, is it necessary for him to go clear down to the rafters and install new 5/8 OSB, or should he be able to make adjustments to the roof and ridge framing by installing battens (and shimming as necessary) over the top of the old layer of shingles? Also am I right in thinking that once he removes the metal it should be replaced by new metal? Thanks for the advice.
Guest User
2017-08-24 14:11:55.000000
Thanks for the quick reply Todd.
Guest User
2017-08-24 14:39:56.000000
Can you tell me how many screw are there in a 12 ft batten bored
Guest User
2017-09-05 16:06:08.000000
I would like to know more about exactly what type of panel was installed. However, I would say that the battens probably were not essential though they can enhance energy efficiency. As far as underlayment, I strongly recommend it to prevent abrasion between the back side of the metal and the granulated shingle surface. I also interpret the International Building Code as including underlayment as a requirement. However, the code is not applicable / in place in all areas. Additionally, not everyone interprets the code the same as I do.
Todd Miller
2013-11-21 14:43:41.000000
Elton, that does not sound unreasonable. The batten spacing specification will be based upon exactly what metal roofing panel you are installing. The manufacturer should be able to tell you what is required.
Todd Miller
2014-08-21 05:31:06.000000
Andrew, once the old shingles are stripped, the plywood needs to be covered with underlayment even if you apply battens. Some products can be installed on battens. Some cannot be. Some must be. So, basically, part of that decision comes down to the product you choose. However, trailers often have moisture issues. Putting the roof up on battens will help prevent creating a situation where dew point occurs in the plywood decking causing condensation. Putting the roof on purlins will help keep your roof deck a little warmer which, in order to avoid condensation, is a good thing. I would absolutely not remove the ridge vent. We need to make sure that moisture generated inside the home is vented outward so that it does not condense in the attic.
Todd Miller
2014-08-22 05:06:06.000000
Hi Lynn, The International Building Code allows up to two layers of roofing on residential buildings. This includes if the first layer is shingle and the second layer is metal. The low weight of metal helps to support this practice. This code is not enforced in all areas but I am not aware of any local or state codes that are as you have been told. The only way to know for certain would be to contact the building officials with jurisdiction in your area. I will say this ... it's not unusual to see 3 or even more layers of roofing on some buildings. This though could become a problem if the home is sold in the future and the home inspector or new owner's mortgage company wants to take exception to what was done.
Todd Miller
2016-09-22 11:18:51.000000
Thanks, Misty. I believe that I just emailed you direct to address your questions. Please let me know if you do not receive my email.
Todd Miller
2017-05-01 14:33:49.000000
The lathe boards should make up for small amounts of unevenness from missing shingles. They will not make up for larger dips and swales in the roof. Here is a link to a short video regarding battens that may be informative for you: https://www.youtube.com/watch?v=pEWcwNg29Ag You probably can cut back the decking at the ridge form the outside though your ridge boards will require you to cut back pretty far and that will likely then require a custom over-sized ridge vent. Keep in mind, though, if you have not soffit (eave) vents and a clear pathway for air to come in and travel to the ridge, a ridge vent will not function and, in fact, could end up drawing water in at the ridge or pulling moisture in through the home's walls.
Todd Miller
2017-05-02 05:10:25.000000
Crystal, first of all, what's been done is not unheard of. However, I do have some questions. Where are you located? Is there any attic ventilation at all in the home? Have you ever had any issues with condensation in the home or ice dams on the roof?
Todd Miller
2017-06-08 04:59:49.000000
Gary, I receive that question several times a month believe it or not. Here is one of the things I have written about it which I hope will be helpful. If you have specific things going on with your situation / home that concern you, feel free to email me your questions. todd@asktoddmiller.com https://www.asktoddmiller.com/articles/metal-roof-battens/
Todd Miller
2017-08-20 19:26:34.000000
Eric, Unfortunately I have no way of knowing exactly how bad the current situation is. All I can do is defer to the contractor who is seeing things first hand and has worked on the roof. Battens are not easy to install in a way that makes up for problems. It may be possible to remove and re-install the panels without damaging them ... but it may not be worth the extra headache.
Todd Miller
2017-08-24 14:25:14.000000
If you are referring to fastening horizontal batten boards, I would fasten them into every rafter.
Todd Miller
2017-09-05 21:08:59.000000
Kenneth, Can you post a picture or send me a photo at todd@asktoddmiller.com? One option would be to remove the old shingles but I do wonder a bit if what you're seeing is from the shingles or perhaps something else.
Todd Miller
2017-09-12 10:44:21.000000
Thanks. This is unusual ... if it seems to be related to the shingle tabs then, without being there or seeing photos, I sure can't argue with that theory. Could it also be caused by overtightened fasteners? Yes, probably. Uneven decking could cause it as well. I would probably opt for removing the shingles or using purlins (assuming union is okay with that) rather than go the foam route. I am just not a fan of foam beneath metal roofs.
Todd Miller
2017-09-13 13:29:25.000000
So Todd- In your opinion (considering the expense) is it worth while to apply 1x4" purlins before installing the panels? The panels are 3 ft. wide ? Steve Saxon
Steve Saxon
2014-11-04 14:31:14.000000
Todd- In your opinion is it necessary or even logical (considering the expense) to apply batten boards before installing the panels. Also couldn't this process also be a problem after the install when walking on it?
Steve Saxon
2014-11-04 14:47:05.000000
My roofing contractor is attempting to install a new metal roof over the existing shingles. We are getting very definite visible ridges at the end of the shingle tabs. Should he be using furring strips or would it be better to use a foam underlayment material between the shingles and the metal? We have stopped until we find a solution. Ken Carpenter
Kenneth Carpenter
2017-09-12 10:36:15.000000
The material is from Union Galvanizing. It is their "5V" panel in 26 ga. A Slip layer is between the panels and the old shingles. Is it possible that the problem is caused by over torquing the fasteners (screws)?
Kenneth Carpenter
2017-09-13 09:32:38.000000
+1 Metal, depending on the panel, can be installed either with or without battens. The lack of underlayment or slip layer is wholly incorrect in my opinion though regardless of application.
Eric Novotny
2013-11-22 07:43:13.000000
John, Quite a normal application and done all the time. If you are looking for above decking venting (i.e. additional cooling), so folks will strap the roof for a vent space application.
Eric Novotny
2016-09-14 07:50:25.000000
Sounds more like a contractor that is trying to scare someone unless he is providing more data than that. A roof over is a pretty normal and well accepted procedural approach. Where is becomes and issue is with multiple layers as Todd mentioned.
Eric Novotny
2016-09-22 11:20:28.000000
They make bath fan vent caps that will mount on a straight section of piping.
Eric Novotny
2017-06-09 11:06:44.000000
Is there an attic below? If so, just go down there and extend the pipe.
Eric Novotny
2017-06-09 11:48:41.000000

looking for metal roof - have been told to lay insulation barrier over existing (1 layer of) shingles and metal on that and another contractor says the correct way is always purlin and then the metal - the housecurrently has ridge venting - I am confused - what is the correct approach - Union Corrugated is the supplier of the metal to both contractors. Whats the best thing to do?

2018-05-06 13:38:02.756215