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Your experience with this?

The roofing supplier, Berridge, in San Antonio, specifies a single layer of "#30 felt," their words, not mine. No mention of an ASTM spec for the felt.

And as we all know, #30 felt is not a waterproofing.

But the coating on the Huber plus the seam tape, does as good or better a job of waterproofing and vapor barrier when compared to the #30 felt.

So, how has the Zip with tape, under standing seam steel, worked for you?
 

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Felt acts as a vapor barrier and as a slip underneath the roofing. We typically use two layers of 15 pound because the total material is less expensive, experience says that one layer will get torn up faster while working on it, and it's nice to have a fresh layer as you install.
Especially on new construction if the roof metal is not going on right away. The UV rays will just kill tar paper. Most metal specs call for 30 pounds of felt, single layer, or equivalent. The two layers work best for us.

Mike
 

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I cant say I have experience so forgive me for commenting anyway. Given the nature of the roof material and the sheathing I agree that its not needed.

On another note, the paper may allow easier movement when expanding and contracting as well as preventing nail heads or humps from telescoping through the metal.

Im stuborn I would use CDX & felt. I stick to old ways.
 

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Your experience with this?

The roofing supplier, Berridge, in San Antonio, specifies a single layer of "#30 felt," their words, not mine. No mention of an ASTM spec for the felt.

And as we all know, #30 felt is not a waterproofing.

But the coating on the Huber plus the seam tape, does as good or better a job of waterproofing and vapor barrier when compared to the #30 felt.

So, how has the Zip with tape, under standing seam steel, worked for you?

I would say felt is not needed, that is what the zip is designed for. I would never use felt anyways.

Felt tends to leave nasty residue marks when you walk on the felt then the steel. Also if you fasten the felt with caps they will shadow through the steel and looks hideous. Same goes for any staple that is improperly installed.

30 lbs felt is more durable than two layers of 15 and takes less man hours.
 

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I would say felt is not needed, that is what the zip is designed for. I would never use felt anyways.
That's the difference between your opinion and the manufacturer of the metal.


Felt tends to leave nasty residue marks when you walk on the felt then the steel.
Buy a bottle of Simple Green and don't walk on the steel any more than you have to.

Also if you fasten the felt with caps they will shadow through the steel and looks hideous. Same goes for any staple that is improperly installed.
The same applies to any underlayment of any kind.

30 lbs felt is more durable than two layers of 15 and takes less man hours.
It may take less man hours, ( nominal) but there is no way it is more durable than 2layers of 15 lbs 1/2 lapped at the seams of the first.

I've seen wind blown rain get through a single layer of 30 lb felt, I've seen it go through the expensive high tech underlayment, but I've never seen it get through 2 layers of 15 lb.

The old Yankees that used to wrap their buildings with 2 layers of paper had it right, and it has worked for alot longer than any of us have been around.

Mike
 

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Berridge allows for a single layer of Titanium UDL 30 or 50 depending on the product being installed. We install UDL 50 under all of our standing seam with the exception of open purlin steel buildings.

Throw the felt paper in the garbage where it belongs and enter into the 21st century. If you are using tar paper you had better be installing a slip sheet over it if your are installing standing seam on a warranted project.

Titanium acts as a slip sheet and underlayment all in one and still weathers for 6 months without issue.

I don't like calling any lapped underlayment "Vapor Barrier" due to the fact that it simply is not. Most commercial spec's these days are calling for a peel and stick vapor barrier like Grace, Firestone, or Carlisle under all systems where vapor barrier's are required. Then you install your ISO, Vent board, nail board, dens deck etc.

I honestly have no idea why architects are specifying tar paper or why roofing contractors are using it anymore. I see it from time to time:blink:. Shingles over tar paper and the Archi wont budge. STUPID
 

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Joseph A. Capece
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I've been using zip-roof exclusively for the past 5+ years (honestly can't remember the last time I used anything else). With that said, I've never had one NOT leak. Even with nail heads flush to the surface & zip tape rolled with their fancy j-rollers. Unless every nail head is taped over & rolled, I don't see that problem being solved. Felt paper is cheap insurance.
 

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I've been using zip-roof exclusively for the past 5+ years (honestly can't remember the last time I used anything else). With that said, I've never had one NOT leak. Even with nail heads flush to the surface & zip tape rolled with their fancy j-rollers. Unless every nail head is taped over & rolled, I don't see that problem being solved. Felt paper is cheap insurance.
If everyone leaks why bother? Or do they just leak a lot less?
 

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That's the difference between your opinion and the manufacturer of the metal.




Buy a bottle of Simple Green and don't walk on the steel any more than you have to.



The same applies to any underlayment of any kind.



It may take less man hours, ( nominal) but there is no way it is more durable than 2layers of 15 lbs 1/2 lapped at the seams of the first.

I've seen wind blown rain get through a single layer of 30 lb felt, I've seen it go through the expensive high tech underlayment, but I've never seen it get through 2 layers of 15 lb.

The old Yankees that used to wrap their buildings with 2 layers of paper had it right, and it has worked for alot longer than any of us have been around.

Mike



Tell me how applying grace modified underlayment will show through the steel? Its all self-adhesive . Use the right materials or dont install steel roofs.

Cant remember the last time I even touched felt. 15 lbs felt more durable than 30 lbs :laughing:


I'll leave you to your felt paper and your simple green :laughing:
 

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I've seen wind blown rain get through a single layer of 30 lb felt, I've seen it go through the expensive high tech underlayment, but I've never seen it get through 2 layers of 15 lb.

Mike

I've seen wind blow that crap paper right off the roof, but Ive never seen it blow off my Titanium with 100 x less fasteners
 

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I've been using zip-roof exclusively for the past 5+ years (honestly can't remember the last time I used anything else). With that said, I've never had one NOT leak. Even with nail heads flush to the surface & zip tape rolled with their fancy j-rollers. Unless every nail head is taped over & rolled, I don't see that problem being solved. Felt paper is cheap insurance.
It takes alot of water to seep through a nail, I even doubt that possible under 6 months.

How long are your roofs being exposed without shingles?
 

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Tell me how applying grace modified underlayment will show through the steel? Its all self-adhesive . Use the right materials or dont install steel roofs.
Do you actually listen to yourself, or are you one of those guys who just spew out whatever is on the tip of your tongue?
You were talking about plastic caps and inproperly installed staples showing through. The Same would apply to any product installed in that manner:blink:

Grace modified is a great product, but the added cost is not for every project. The op asked about installing over felt or none at all. My experience for the last 24 1/2 years has been that which I stated above. It has a proven track record unlike much of the new and improved crap which has come and gone. Many of the homes that my crews have installed on are existing construction. Integrity of the water barrier during the job is important.
Cant remember the last time I even touched felt.
There's probably a lot of things you can't remember:drink:
Obviously you are one of those who can't offer your opinion without congratulating yourself on how wrong others are and how right you are.

It's ok, I can take it. I've seen plenty of your kind sending me job applications over the years.

Mike
 

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oldschoolcarp said:
Do you actually listen to yourself, or are you one of those guys who just spew out whatever is on the tip of your tongue? You were talking about plastic caps and inproperly installed staples showing through. The Same would apply to any product installed in that manner:blink: Grace modified is a great product, but the added cost is not for every project. The op asked about installing over felt or none at all. My experience for the last 24 1/2 years has been that which I stated above. It has a proven track record unlike much of the new and improved crap which has come and gone. Many of the homes that my crews have installed on are existing construction. Integrity of the water barrier during the job is important. There's probably a lot of things you can't remember:drink: Obviously you are one of those who can't offer your opinion without congratulating yourself on how wrong others are and how right you are. It's ok, I can take it. I've seen plenty of your kind sending me job applications over the years. Mike
A little hypocritical don't you think
 

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Joseph A. Capece
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If everyone leaks why bother? Or do they just leak a lot less?
Keeps MOST of the water out until we're completely dried in. It lets us focus on getting interiors framed out & subs in while we're outside trimming and getting prepped to get the roof on.
 

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Joseph A. Capece
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It takes alot of water to seep through a nail, I even doubt that possible under 6 months.

How long are your roofs being exposed without shingles?
My point isn't how much it leaks, but that I've almost never seen it keep 100% of the water out. It might be more of a factor of the guys not keeping the tape 100% wrinkle free than the nail heads seeping water. Either way, the felt before roofing is cheap insurance.
 

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My experience for the last 24 1/2 years has been that which I stated above. It has a proven track record unlike much of the new and improved crap which has come and gone.

It's ok, I can take it. I've seen plenty of your kind sending me job applications over the years.

Mike

24 1/2 years and you haven't fully understood the best methods for installing steel.
Felt might have a good track record for shingles wherever it dont freeze but steel roofing is a completely different animal.

You obviously know felt is not a waterproofing material, especially with 1000s of staple holes or whatever you use.


Now what happens when there is thermal bridging through the attic as there is in 99.9% of houses?
The underside of the steel will condensate like crazy depending on how much thermal bridging occurs . As we all know, felt is not waterproof.

Now in your 24 1/2 years experience.... where is that condensation going to go?

Some will get shed by the felt and some will penetrate the deck by weeping through your fastener holes. Year after year the deck will be exposed to moisture. we all know what happens then.

This is why felt is not the preferred method. High temp ice and water shield should be applied on entire roof.
Throw that felt in the garbage or hang it on your wall as a trophy next to your simple green as past memories a :drink::drink::drink: .. to the good old days

But what do I know,


The OP asked for our experience, there is mine

Sometimes you dont follow manufacturer recommendations and do things the proper way.

I thought zip decking was supposed to be water tight but apparently not the case from experiences shared on this thread.
cheerio!!!
 
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