Underlayment

Eric, another thoughtful post (so what else is new ;) )

My practice is informed by the local conditions. The hardest part for most roofs in our environment, is the late winter/early spring time when the snowfall is ample, the temperature swings between about -10/15C to 0/5C happen almost daily, with consequent melting and refreezing. Under those conditions, ice dams form even on well insulated and well-ventilated roofs. If the appropriate underlayment is not in place under the shingles and the flashings, you will (not may, but will) get water infiltration and leakage.

In response to these conditions, much of the local trade uses Grace I&W as the panacea - stick it on, and the problem is gone. Sure it is. Until it doesn't work, and then everyone scratches their heads and behinds and wonder why the miracle didn't happen this time. As you pointed out, Eric, leaks happen in sidelaps, and in other places, and rarely due to penetration due to nail-holes. Peel and stick membranes do not adhere well to masonry, or metal, and those surfaces need to be primed with roofing cement or similar material to ensure adhesion and water-proof installation. Which most do not bother to do (ick - it's messy! It slows down the "flow"!). So it's not enough to use the right materials, then have to be used in the right way.

I like the good ole fashioned 30 pound felt. Most jack-a- lanterns around here use either 15 pound or none.

Residential roofing has always been about production to some degree but in the last 10 years it has become mostly all about production.

The reason ice/water shield, synthetic underlayments and the like have become more popular lately is because, Contractors are looking for ways to help make up the poor quality of their installations performed mostly by their hispanic "subs".

The thinking is anything they can do to lower the amount of warranty issues.

MAYBE THEY SHOULD CONSIDER HAVING THE ROOFS INSTALLED "PROPERLY" TO BEGIN WITH!

:woohoo:

I was burned in the 80's by an early lightweight felt replacement that my tile supplier was touting and became gunshy about others. Although I recently gave a bid on a lift-and-relay underlayment replacement and was thinking "why did I ever use this crap", then it hit me. That crap had been on for almost 30 years.

Now, my underlayment of choice is Titanium 50. Any roofer that criticizes that stuff is either stupid-cheap or hasn't tried it. For peel-and-stick I prefer HT versions from either Grace or CT.

I still use UL 15# and UL 30# and whichever I&W I get for valleys and eaves. That said, I don't worry about it too much. I expect my slate and copper to outlast anything under them and still not leak when it all turns to dust.

The Underlay Story The execs at a major shingle manufacturer felt they needed to increase sales somehow. Memos were sent to all departments in search of ideas. Some months went by and a fellow in marketing wanted to present an idea. A couple, really. He met with the execs one day and said “Let’s sell felt. The only people in the market are Bird and JM.” The execs all spoke up and said their entire market share there was new construction! “Only builders buy the felt to keep their projects dry until the roofers come and install the shingles. The roofers are often installing our shingles without felt. And it can’t be used on a re roof. What the heck do we want to sell felt for? The only felt we need is the 12” rag for our shingles. There will never be a need or market for us there. It could open us up to some new liability! And it isn‘t used under tin! Follansbee will void their warranty if they find felt under tin. We can‘t sell it there. There isn’t a roof in the world that requires felt…. How are you planning on selling THAT?” Get out of here with that hair-brained scheme!” “Please! Just give me a minute and you’ll see the logic! Please!” “You have 10 minutes.” “Here’s the deal. Our 15 year shingles regularly last 17-22 years minimum. And our 5 year warranty never needs to be honored, right?” Nods, and “yeses” from the execs. ‘So?” “ We will need to market ourselves as a leader to be envied. Let’s offer a ’7 year’ warranty ’if’ installers use our felt under our shingles! It’s a win-win. The shingles will go the term with or without the felt, but we can open up a whole new market and give glossy brochures to dealers to hand to installers and it only costs us pennies. The installers will do our marketing for us! We’ll always be able to ‘prove’ installation error if any warranty issues ever occur anyway. We can’t lose….It‘s a win-win and we get a larger market share all around.” “Research is showing that anybody less than 50 year old gets caught up in the hype that glossy brochures, TV ads, and radio ads spout. Any glossy ads we print will be taken as gospel. And it’s real easy to brainwash people if we were to do TV ads. Ignorant people soak them up like sponges! Older people tend to take ads with a grain of salt and figure that if it‘s worth being on TV, it‘ll be announced during the news as a news item. They seem to know the difference.” “The established and older roofers will never fall for that line.., but we could give it a try for a limited period of time. It’s your job on the line though!” “No problem Boss. We’ve been looking hard into this and we believe some hard pressed companies will use the ploy to increase their sales. And the newcomers to the roofing industry won’t know any better anyway. We won’t tool up for this, we’ll order from other makers and have our names stamped on the rolls. If this takes off, we’ll see about tooling up to make it ourselves, maybe. Who knows for sure. I do believe we can even make a market for it in the metal roofing side of things. Bill, Bob, myself a couple of others are looking into now.” “Joe and a small team are working on their own time to see if they can come up with some form of sticky felt. They heard a rumor that a company is working on a product that can be used on eaves to help with ice-dam issues. If it’s as good as rumor has it, even jacklegs will be able to do roofs with too many leaks further helping us avoid nay warranty issues. If it has merit, we we can come up with a marketing gimmick for it too.” “Just think ‘underlay’ and we’ll market the term and use it all the time until people start forgetting the roof itself and the underlay becomes the priority. Like I mentioned before, there is plenty up sell potential here and no liability beyond the pennies on the dollar we’re already liable for anyway. How can we lose?” “OK, we’ll also have legal look into all facets before anything goes public! One slip and you’re fired!” “Remember, this will have nothing to do with roof performance, it’s all about marketing! The New buzzword will be ‘Underlay!’ We will be working on selling an underlay for other standard systems like EPDM, TPO, and the like. It’ll be a harder sell, but if they’ll buy the one idea, I believe that in time we can sell them the other.”

We installed THOUSANDS of roofs with no felt in the 50's and 60's and early 70's

tinner666 said: If it’s as good as rumor has it, even jacklegs will be able to do roofs without too many leaks further helping us avoid any warranty issues.

:laugh: :cheer: :unsure: :P :blink: ;)

I started roofing in 1985. We never did a roof without there being felt on it that I can recall. However, just to be quite frank with everyone we did many back in the day just re-using the old felt.

I also remember tearing off a lot of roofs that had bare wood underneath.

What gets me is that a 2sq roll of 30# felt might weigh 40lbs. should it not weigh 60?

roofermann Said: What gets me is that a 2sq roll of 30# felt might weigh 40lbs. should it not weigh 60?

It's not 30# anymore. It's #30

UL 30# probably weighs 50# or so. It's twice the size and thickness of #30. Same for UL 15#. It's thicker than #30 and the much heavier. Warrior Brand, Another is from BC. Only one supplier around here has it.

In the early 80's I worked a few weeks at a double wide mobile home manufacturing plant.

They gave us a large roll of black plastic that covered one entire side of the double wide.

Just roll it across ONE time and staple it down and woo lah, your done!

Does this count as actual underlayment?

It was after all laid under! :laugh:

Rolled goods weight is measured by the amount it weighs per roofing sq. Now a roll of#15 then should weigh 60 lbs and #90 should be 90lbs all I know is that back in the early 70's we were buying #15 and #30 for $ 4.50 a roll, 100 steep asphalt 4.50 per 100 cwt check the prices today lol

Daryl, 15# felt weighed bout 64 pounds, because it had 4 squares of coverage and 432 square feet of total area with the laps. Now they sell #15 (number 15) felt and that weighs about 30 pounds for 4 squares. It is a lot different and cheaper, but it costs a lot more than the old felts did. That just shows how much purchasing poser the dollar has lost over the last 30 years. it is workth about 8 or 9 cents compared to 1980 and about 3 cents compared to 1965.

Inflation is a nasty little crime that steals money from everyuone but the people that are running the printing presses and the bankers that lend nothing and charge interest for it.

I passed by a new construction home the other day that had some kind of synthetic underlayment installed that had been on the roof for some time.

That stuff had more wrinkles on it than a 100 year old roofer! :laugh:

Paul, what you say about choices being informed by local conditions is the trump card for sure. If you're going to play trumps, I'll follow you; just show me where to sign. You and Darryl must have about the toughest conditions to deal with of anybody here, although I have to say I can't imagine ever having MikeNZ's patience in dealing with his weather-driven site conditions.

We just worked a half day today to finish drying in one. Our first week of 90 degree days pretty much smoked us after months of mild mild conditions. Suddenly they call for chance of rain. You can just never take anything for granted, or you are a fool if you do. I know it well because I've tried quite a few times and suffered for it.

Eric, our mantra is "strip only what you can waterproof the same day". We've had a few close calls, and the new modern way of having the weather radar on our cell phones does help. Although I have seen also the "miracle" rain falling out of an apparently (according to the weatherpeople) cloudless sky.