# Metal Roof Over Shingles??



## LeeFowler (Nov 3, 2012)

Today I saw a company putting a standing seam directing over shingles with asphalt felt between. The panels were probably 30' and had no striations. I can't imagine it's going to look all that great after it oil cans and telegraphs the shingles below. 

We offer the option of complete tear off but our base bid is for lay over when it comes to screw down. It's perfectly acceptable to manufactures and insurance companies, so I'm okay with it as well. On the note of screwing threw the ribs, I have always thought it had to do with getting as tight a fit as possible. Screwing through the rib seems to lead to over-tightening of the fasteners. 

When it comes to standing seam we will only install over a clean deck.


----------



## TimelessQuality (Sep 23, 2007)

Randy Bush said:


> .... sometimes you just have to do what you have to .


... yup:whistling


----------



## hootrod351 (Jul 3, 2013)

agree, thing called RE-ROOF. ive done three now over old shingle roofs, one on a tear off and one on new construction. i guess if you put them side by side you might see a difference, but when the owners are standing there with a check, or cash, in hand as im finished and cleaning up, well that tells you there happy.


----------



## Joasis (Mar 28, 2006)

This subject can bring out the best and worst in the arena of personal opinions, many times unsupported by anything except anecdotal tales of experience. 

You guys have to remember that experiences vary across the nation, and what works in the southwest may be unacceptable in other areas. 

But what comes to mind is in the methods....just like my experience with where we screw down metal over the rib instead of the flats. There are members who will gladly point out the UL "acceptable or recommended" method, and then there is the way many of us learned, decades ago about ribbed galvanized metal.....always nailed through the rib because even a fool can see water does not run on the top of the ribs. 

Now we screw them down, and yes, you must be careful not to overdrive.


----------



## hdavis (Feb 14, 2012)

Esthetics and performance are still the keys. I've never nailed or screwed through the flat.


----------



## TimelessQuality (Sep 23, 2007)

hdavis said:


> Esthetics and performance are still the keys. I've never nailed or screwed through the flat.


Not even at the eave?


----------



## red_cedar (Mar 30, 2005)

Trouble is a lot of manufacturers suggested installation methods are screws on the flat.
Personally I feel it to perpetuate the metal industry with replacement down the road, 15 -20 years. Cant be for best waterproofing installation methods.


----------



## Joasis (Mar 28, 2006)

It isn't "trouble is"...it is method. UL recommended doesn't apply in every case, and what the insurance company will accept is what sells. 

There are homes around here that are going on 20 years plus with metal....never a replacement.....yet. There are home here also that have had 5 or 6 shingle roof replacements in 10 years.....and think about the cost. To everyone. 

There are farmhouses that have had roofs installed in my grandfather's time that were galvanized metal and they are still standing. Outlasted even the best shake roofs. Might not look good...but they are there....nailed with lead washer nails...through the high ribs. 

You just cannot beat the true test of time.


----------



## hdavis (Feb 14, 2012)

Joasis said:


> You just cannot beat the true test of time.


X2:thumbsup:


----------



## hardtroofing (Jan 23, 2015)

I greatly appreciate all of your thoughts and ideas, I feel a lot more confident about doing a layover. I have been installing double-lock since the late 90s and this goes against everything I have learned. I will let you guys know how it goes!
Thanks again
David Reinhardt


----------



## Cbs91 (Jul 24, 2014)

A few builders here have tried shingles on high end constructions and all have deteriorated rapidly in only a few years. It's all metal roofing here with the odd exception of terracotta/ concrete tiles. Interesting your strapping you guys are using. Do you have available metal top hat sections (like furring Channel apprx 3 inches 

That's what nearly everyone is using here and attach directly to rafters/trusses[


----------



## Cbs91 (Jul 24, 2014)

^^^ don't pay any attention to my tabs in above photo.... 😔


----------



## illbuildit.dd (Jan 7, 2015)

Joasis said:


> I have seen it done hundreds of times, and the fact is, a screw down, exposed fastener roof over shingles is not a big deal. We have done many as well when we did a lot of roofs, and there has never been a problem one. Insurance allows it, and frankly, if you are covering a roof that has been totaled because of hail damage, 9 out of 10 times the roof is still good...just some dents or cracked shingles. Covering this with 26 gauge metal taking care to not lay over anything that will cause an issue, and all is well.
> 
> One more advantage: If you leave the existing roof in place, and cover it with metal, you will have a very low risk of damage from weather, and price can sometimes be the driving force.
> 
> Of course, you can express opinions all day long about it isn't right to cover shingles with metal panels, but the fact is it works.


Ditto. I've done it three times being what the budget is and what's accepted by insurance. Do you use felt over the shingles?


----------



## midmich (Dec 16, 2014)

Depending on your local building codes you might have to tear off. But as long as your within your local building codes, not tearing off the old shingles won't change the warranty received from the metal coaters or panel manufacturer. The biggest thing is putting a permanent vapor barrier in between the old shingles or if you tear off over the plywood or osb. There is some great benefits to not tearing off for 1 No tear off and removal of old shingles. 2 When the new furring strips 1x3 or 1x4's are nailed at the each rafter, it gives you a very strong base to fasten your panels to. Even when you tear off you are still relying on the old osb or plywood to handle the winds. (If OSB can't handle holding shingles during high winds, Do you really think you won't have problems with metal that is fastened to the same old wood.) As for the worry about bad wood. If there is a problem with bad wood Tear that small section out replace the wood and then put a new sheet there and some Ice and Water and your good to go. 3 It is very cost effective to not tear off and you won't have to worry about rain leaking in during the new roof install.


----------



## hardtroofing (Jan 23, 2015)

Responding to Midmich, You have the same thinking I do about the whole deal. Installing new 1x4 s over the existing shingles will give you a better nailer.
Now hopefully I can be competitive in the market.
I seen I Colorado 20 years ago they were decking a roof with ply and then installing grace ice and water after that they installed 1 x 1s over the roof joist and then installed ply again, then 30lb felt and shingles, ( They called it a Cold Roof ) 
I believe that using this system is somewhat comparable to a Cold Roof.
Thanks again for all of your ideas and opinions.
David Reinhardt 
www.hardtroofing.com
https://www.facebook.com/pages/Hardt-Roofing/410198825813022


----------



## dDubya (Feb 1, 2013)

HardT: Sort of. The air can move around through the ribs but it can't flow from bottom to top and get rid of the hot air because of the foam closures.

If you install vertical straps then horizontal and make a way for it to vent, then you have an awesome cold roof.


----------



## 1985gt (Dec 10, 2010)

Cbs91 said:


> ^^^ don't pay any attention to my tabs in above photo.... 😔


:laughing: I'm guessing the last tab is why you only have 22% battery left? 

Most people wouldn't have noticed until you pointed it out.:whistling:laughing:


----------

