Tar and Pebble Roof


#1

I own a small commercial building about 20Squares which has tar and pebble on it. I would like to remove it and install new EPDM. Can someone briefly explain the process of removing a tar and pebble roof and then installing an EPDM? Could I go with the EPDM over the tar and pebble? Thanks


#2

were at you located?

gweedo.


#3

In Connecticut


#4

If theres only one layer of roof and all wet material is removed prior to installing the new one it would be fine to go over it. A foam iso board insulation at least 1" thick over the built up roof is what I would recommend.
Removing the old roof is always a better option.


#5

I would take a core sample “test cut” to see if there is wet insul and to check the deck type and fastener lenths. In many cases its ok to broom loose gravel then screw down a layer of iso then your menbrane. Do NOT use fiberboard.


#6

danny,
call several roofing contractors in your area and get at least 4 estimates. then call a local roofing supply store in your area and see if he can recomend a contractor who is approved by the epdm mfr to install this product. do the research first. have you considered a thermo plastic such as tpo or pvc? maybe even a modified bitumin system. there are dozens of solutions out there.what does your business do? this could have a bearing on the right system for your building,


#7

I used to be an old BUR and EPDM roofer, before I became a consultant back in the late 80’s. Anyway, like roofboss said, I would look into TPO as an option instead of EPDM.


#8

Why dont you like fiberboard?
Iso will cost them much more and if they have dry insulation and its the yellow nasty fiberglass they dont really need the extra r value.
They could go with a 1/4" secure rock as a recovery board if he has lots of money to spend.


#9

Wood fiber is the cheap way out and is an inferior product compared to iso especially when doing a layover.
I feel epdm is a tried and true product. Tpo has limited time on the market not to say its a bad product. I don’t understand why you guys dislike epdm so much to steer people away from it.


#10

inferior? I dont think so. If it is fastened per the roofing material manufactures specs it is fine.
Do you think it is inferior because of wind uplift, R value, or some other reason?
Its wind uplift is less and it has less R value, but I wouldnt say its inferior. It is just different. It is just about the standard for an overlay in about any regoin of the US.

We have some TPO roofs in STL that are a good 12 years old or a bit older. They look great, have no shrikage and look to have a decent life ahead of them. I dont dislike EPDM, it has its place. But, in this day and age of everything being energy efficient EPDM doesnt cut it. White EPDM membranes (not painted) are inferior to the traditional black. White is the new black in roofing.


#11

Wood fiber has its place and in my opinion thats for people looking to save money at the cost of quality. I have put down alot of the stuff and if done right its ok but over an old bur I just think it looks uneven and cheaper. Plus it compresses easier especially if it gets wet at all. Sometimes roofs leak for many different reasons and wood fiber wont hold up. Why use it if you don’t have to?

Just because all the rage is reflectivity doesn’t make white plastic a better waterproofer than epdm. And if you live north of the Mason Dixon line the numbers would show white roofs save very little energy over the entire year. Especially when most are brown and dirty after the first year anyway.


#12

I like EPDM adhered, not ballasted. I do not like the EPDM with the factory white coating. I have seen too many failures, with the coating. Even though factory applied, it releases, causing seam tapes and field seams to break loose. I’ve had good success with .045 and .060. I like it for the reason that it is easily repaired if struck by falling objects.
With cooling being a concern, I would look at installing more R factor and not be too concerned with the color. My personal experieces with EPDM have all been positive. Never a call back for failure.

As for TPO, I just don’t know that much about mechanically fastened systems with heat welds, therefore I can’t really comment on their longevity.


#13

Im with you. EPDM is a proven great roof if installed by a competent crew. Its by far the bigest flat roofing material in the Boston area. Sarnafil was real big for a while but has droped off a bit since Sika bought them out. JP Steavens was a fad for a while as was Cooley. Modified bitumen is extinct and BUR is almost extinct. That is just regional im sure.


#14

[quote=“rooferama”]I like EPDM adhered, not ballasted. I do not like the EPDM with the factory white coating. I have seen too many failures, with the coating. Even though factory applied, it releases, causing seam tapes and field seams to break loose. I’ve had good success with .045 and .060. I like it for the reason that it is easily repaired if struck by falling objects.
With cooling being a concern, I would look at installing more R factor and not be too concerned with the color. My personal experieces with EPDM have all been positive. Never a call back for failure.

As for TPO, I just don’t know that much about mechanically fastened systems with heat welds, therefore I can’t really comment on their longevity.[/quote]

Adhered EPDM is definitely the way to go instead of ballasted. In fact, here in Houston you can not install ballasted roofs, as rocks become projectiles in hurricanes. They also just passed a new code that requires all commercial roof systems to white and reflective or include a reflective surface like DerbiBrite. It just got passed a few months ago, so we will see how things go, but for now TPO is the primary system that meets the new codes.

As for the EPDM, black vs. white. The black contains more carbon-black, which is what protects it from UV rays. There is less carbon-black in the white EPDM, so it does not hold up to solar radiation as well.