Which is a better concrete tile underlayment?


#1

My existing concrete tile roof in Southern California has an underlayment consisting of one layer of 40-pound felt, leaks like a sieve and I am replacing it.

Which do you think is better as an underlayment for a concrete tile roof in Southern California?

  1. Two layers of 30-pound felt.

  2. One layer of “CertainTeed Black Diamond Base Sheet” (a self-adhering, SBS modified bitumen coated fiber glass base sheet)

On the other hand, if you don’t like either of the above, then what would you use as an underlayment for a concrete tile roof in Southern California?


#2

Why is the underlayment wet?
If the roof is the entry point then that problem needs to be corrected first. You can use silk panties as an underlayment if you want
We go around and around with this same topic.
THE TILE SHOULD NOT ALLOW WATER THROUGH>
THERE IS A PROBLEM WITH THE INSTALLATION>


#3

Yes, there definitely is a problem with installation.

In my opinion, the original installation was substandard (for multiple reasons that even I as a non-roofer can see). And even more sadly, it wasn’t properly maintained by me over the years.

It’s also 20 years old now. Water under the bridge as far as I am concerned. The original 10-year warranty ran out a long time ago…

It’s good to hear that I can save a bundle of money by underlaying with silk panties. My girlfriend has lots of those hanging in the bathroom! :smiley:

For some reason I am under the impression that the concrete tile is just there for show, to protect the underlayment from the sun and the weather and that the underlayment is what does all the real job of waterproofing the roof.

BTW, some prospective roofers want to do two layers of 40-pound felt instead of two layers of 30-pound felt. I gather that 30-pound is more flexible and less prone to cracking (?), but the 40-pound weathers the elements better and can go longer should the tile fail to protect it and go unnoticed for a while (?). They make it sound like a damned if you go one way and damned if you go the other way decision. What’s the real scoop here?


#4

[quote=“Kilgore Trout”]My existing concrete tile roof in Southern California has an underlayment consisting of one layer of 40-pound felt, leaks like a sieve and I am replacing it.

Which do you think is better as an underlayment for a concrete tile roof in Southern California?

  1. Two layers of 30-pound felt.

  2. One layer of “CertainTeed Black Diamond Base Sheet” (a self-adhering, SBS modified bitumen coated fiber glass base sheet)

On the other hand, if you don’t like either of the
above, then what would you use as an underlayment for a concrete tile roof in Southern California?[/quote]

Hi kilgore,
Post some pictures of your roof above the leaky areas
and Krakkerjack can point out your installation issues. I would like to learn something.
I too, would like to install just silk panties or no underlayment at all-as he says.

I am one of the ones who believes that a lot of concrete tile roofs are leaky roofs. I do believe that water gets up under your tile.
I also know that certain storm waters run "up hill"
quite frequently.


#5

40 lb is good as would be full I&W shield. A tile roof in a northern climate is susceptible to wind driven rain and snow issues so underlayment is a very important component. We are starting a Ludowici Clay mission tile install in about two weeks.


#6

Kilgore Trout,
Read the post on page 4 titled “new terracotta tiles leaking”. I’m not gonna get into a pissing match with Bennett roofing. He says you can’t, I say you can, the facts speak for themselves. You decide.
roofing.com/forum/about7069.html

BTW, bennet you did’nt answer my question about why you are using copper slaters nails on clay tile.


#7

What would you use to fasten clay tile :shock:


#8

One who answers a question WITH a question is generally assumed to be avoiding the issue. Why? Not so sure why you are doing what you are doing? It is a simple question.
Do you use grandpas truck and work for his hourly wage also?


#9

If you dont know what a slaters nail is or how it is applied then your an Fking idiot. If you would like to insult my family then maybee you should come to Boston and say it to my face, I WILL promptly twist you into a pretzel. :smiley:


#10

For slate and tile non corrosive fasteners are used due to the very long life of the products.

Krakkerjak, with all due respect you are arguing with a very knowledgeable and experienced roofing professional here.
If you continue you will just look like an idiot.


#11

I asked a question, a very simple one. Copper nails are used for slate mainly to facilitate ease of removal with a slate ripper during repairs, longevity is a bonus, not "the reason"
If there is a study on the comparitive longevity between stainless, copper, aluminium, galvanized nails then i’d like to see it. If not then then the point is rendered moot as it is all guesswork. With regard to using them on tile it would depend on the type of tile used, but the tensile strength of the nail, the weight of the tile, and whether on or two nails are used are all factors that would come into play.
The fact that someone uses grandpa’s tools does’nt lend any credibility, and thinking that it does is misguided. Taking the question in the context it is presented, it could not be construed as an insult. Taking it as such is an indication of the intellectual capacity of the reader. It is also completely irrelevant to this issue.
As for “arguing with the wrong person” my credentials are long and proven, slate and tile for almost 30yrs and in many different countries, including the state of New England. Not that I need to explain them to either of you two…and assuming you can “twist someone you have never met into a pretzel”…well, who’s the Fking idiot?


#12

It is self evident that you are in the wrong Kraker. Tensile strenth of the nail, come on ? LOL. Dope is not good for your brain son. You started this negativity. I will not comment to you at all anymore, if you want to argue go somewhere else. I come to this forum because its a good felling to be able to help others with there roofing problems and questions. Roofing is one subject I know well.
Sincerely
Jim Bennette aka"RooferJim"
J.Bennette Roofing Co inc
Weymouth, Ma 781-331-1908 Pembroke,Ma 781-294-4012 Brewster,Ma 508-896-1860


#13

Getting back to the subject, Ludowici-Celedon is the most common roofing tile in the north east. It can last for over one hundred years. they are still in business ludowici.com/product . they will send you specs for installation if you ask. they recomend copper slaters nails, some tile “like mission tile” have to have a batten grid. they do require a heavy duty type underlayment . I have one to start in about a week or so weather permitting, it is an $80,000 job. Also has lots of copper flashing work involved, I will try to get pictures.


#14

We are talking about a concrete roof that has battens.

Do any of you install concrete roofs without battens?
I have seen it done but i haven’t ever understood how it was a good roof.

The underlayment is more important than the fasteners.
The fasteners could rust and the tile will still be there.
I’m sorry, but contrary to most tile manufactures i dont think One layer of 43 pound glass base sheet cuts it.

When i need to replace a piece of concrete tile,
I use a flatbar,hammer and bolt cutters.
Slaters tool no where to be found.
Never seen a concrete tile with a copper nail in it.
Nothing wrong with that though.

I use Quickdrive screws. strip screws.
Two screws on all perimeters.
One screw in the field.
I would use the Certainteed black diamond.


#15

Yes I would also use a flat bar,a wooden wedge or two to hold other tiles and a regular hammer.the only slate tool I might need for a tile repair is a ripper to free it up or to shear a stubborn nail. What would you need bolt cutters for ? There is not a whole lot of concrete tile up here most are clay. I also like to use red slaters cement for my hips and vallys on tile work. Always new tricks of the trade to learn as they say.


#16

You wont learn it anywhere else because it hasn’t been written yet. I taught myself.

When i say hammer, i mean my estwing drywall hatchet that i use for everything. Lighter than a shinglers hatchet. the hatchet part works better too.

I use my hammer to smash the broken concrete tile in the middle. There will be remnats hanging on to the fastener. I know how to hit it so it will break around the fastener. Then i use my flatbar and my hammer head to use as two wedges.

Your flatbar,ripper wont pull out the screw.
You use the bolt cutters to snap the screw off as close to the batten as possible.
Usually there will be a small stub there but that is OK.
I am using small bolt cutters. The one that is about 18 inches.

then slide the new piece in. Sometimes you need to kick it in.

If everything is still too tight and you cant even kick it in, then i grind a small amount off of the lip that hangs on to the batten.

Small amount of rt600 under the headlap. done.

30 years experiance, all 50 states, no underlayment,just panties krakkerjack knows nothing about this.

lol, Just messin with you krakkerjack!


#17

search tu plus peal & stick .
ive used it alot.
like it.

gweed.


#18

[quote=“gweedo”]search tu plus peal & stick .
ive used it alot.
like it.

gweed.[/quote]

Polyglass TU (Tile Underlayment) plus

I havent done a tile roof since that stuff has been out. If gweedo says thats the best stuff to use.
I believe him.

Gweedo, instead of nails or screws, are you using the tile adhesive? If you have used it, what do you think of it?


#19

lowslopes im ok with the foam.
it suprisingly holds pretty damn good.

but once i get to a steeper roof i still want them
screwed.
i just cant take the chance a roof will start sliding
down in a couple a years.
it just stiffins up the entire structure when you screw evry tile .
you actually feel the difference walkin on it.

gweedo.


#20

Are you being made to install two screws per field tile ?

I will do it if the law requires.

I dont like doing it. Not because its more material and takes more time.
I dont like it because it trully locks the tile in place. It locks the tile in a position it doesn’t want to be in. Then the tile isn’t able to move around to its lowest possible spot in the grooves with the tile below & besides.

This causes more breakage during installation and through out its entire life.
I think the tile will last longer and break less with one screw.

Government knows best!!!