EPDM for 2nd Floor Balcony

I am in the process of building a new home that has a small (7’ x 12’) 2nd floor balcony off of the master bedroom that is partially over the dining room below. The balcony has walls on three sides and will have railing on the open end where it has 10" vertical face that ties back into a shingled sloped roof below. I would like to have EPDM installed and then lay a floating cedar deck over the EPDM.

The question:

Should the EPDM run to the walls (not up them) and be flashed with aluminum and uncured rubber flashing.


Should the EPDM run up the walls with the inside corners folded and not cut.

I have two separate contractors each proposing one of the above. Neither has been able to give me very convincing reasons for their position.

Any advice would be greatly appreciated.

Thank you.


Run the EPDM up the walls as one continuous sheet. Secure the transition from roof-to-wall with a rubber nailing strip or acceptable equal, and then flash the nailer with uncured EPDM. The corners of your roof should be folded into what are known as pig-ears.

Now, if you are going with EPDM beneath a floating deck, make sure you install rubber walkpads or a sacrificial piece of rubber over the entire surface. Also, demand that your roof be comprised of one piece of EPDM without any field laps.

Well, that’s my opinion for what it is worth to you.

The reason not to do this given by the contractor who proposed flashing the wall/roof junction with aluminum and uncured flashing was that I would have to install cant strips to ease the transition from the roof to the wall and that I would have a hard time trimming the junction and interfacing with the siding.

The other contractor simply said that the cant strips were unnecessary and that I could cover the the top of the EPDM with a wide band trim (5/4 x 10 PVC board) with its own drip flashing and that would provide the transition to the lap siding.

Would you agree with the second contractor that I don’t need the cant strips with the EPDM? The first contractor said I was guaranteed to have the EPDM tear at the sharp corner without it.

Thank you very much for taking the time to provide your opinion.

cant strips are not required on epdm roofs.uncured flashing were good in 1983 but not now,contact two more contractors. also most epdm mfgrs have a walkway pad which can be installed over the rubber to protect it from punctures

scap the epdm and cedar idea and have a pvc mambrane intalled that is made for walk decks. is is quite a bit mor expensive but looks better and if there is a leak you won’t have to start pulling up your deck just to find it. The membrane I use is called dec-k-ing by mule-hide products. This is perfect for your application. If you cant find that brand call abc supply and see if they carry i simalar product e.g. dec-teck, deck-rite.


a couple of things…

what do you now use to wrap the oddball stuff if not uncured? I do not do a lot of EPDM work. Why are the uncureds no longer any good?

Arent you supposed to be off racing?

currently residing in sunny arizona. look at the date!!!a pleasant 51 degrees currently.everyone here has winter coats on.

I see…

How about the uncured?

uncureds are still just as good as they used to be. only thing is that if you get old uncured from your supplier it will already be partially cured and won’t work as well. make sure you are getting fresh product. also get the uncured that already has the tape (adhesive) on it. The have much better adhesion than using the glue. make sure you use primer too, otherwise it won’t stick as well.

what is there to wrap with uncured?at best in direct sunlight uncured will last 7-10 yrs.how do you wrap and transition a taped uncured onto the substrate without compromising its integrity…lap sealant?

for repairwork I glue the uncured…is this wrong, roofboss?

aaron, if you are using just plain uncured then you should use glue, but if the uncured is peel and stick then for repair work just clean the area then use tape primer and just stick it down. thats it.

thats it???

All of the these issues you all have pointed out is exactly why we spec so much fluid applied. Even if it is just for the flashings. It is the only real answer to a system that must be monolithic and flashingless. Even Polyglass and Malarkey have begun writing flashingless specifications Using acrylics for thier own installations recognizing the fact that they cannot achieve the same results with traditional methods.

why do you need “flashingless”? and what does flashingless mean?

You would need a “flashingless” system anytime you question the integrity of a coping or a wall flashing. like if you suspect wind is blowing water under flashings, or If the roofing materials are so high that you cant properly get under a counterflashing. It is a better solution because it is more permanent and more cost effective than removing and replacing. When you start using this method you will never find yourself thinking, geez it really comes down to the bead of caulking to seal the wall flashing, coping laps, gutter seams etc… on a low slope you could literally have one product from ridge to eave over the drip edge into the gutter and up the parapet over the coping and adhered to the CMU on the outside… seamlessly. You just eliminated the sheetmetal guy from your roof job.

It would be described as a monolithic and seamless transition from any roofing material and abuting surface.

any change of directionneds flashing, seamless or not…

fluid applied seamless is great, for some situations, but I would never use anything less than a polyurea for my seamless, unless youre lookin g for R factor…then i would like to see foam and acrylic. That is the only thing my empirical data has shown it is good for…reflectivity.

I have a great spec for a cool roof with polyurea waterproofing, and acrylic UV inhibitor.

There are certainly techniques that need to be done inorder to do it properly with acrylic, just like anything else. You stated a perfect limitation for Polurea because it is unreinforced and is too hard to transition the way I described.
But I must disagree with your data, or you dont have the data that I do which proves it to be soundly successful many times over .

Do you know anything of polyurea? Why would you want to reinforce polyurea? The thicker you make it, the stronger it gets, unlike any other roofing product on the market.

Too hard to transition? Puhlease! Maybe a little research is in order?

[quote=“AaronB.”]any change of directionneds flashing, seamless or not…

These are your words.
My data and a couple thousand projects say that a fully reinforced fluid applied high performance acrylic system will transition multiple direction changes without any help from other products like metal flashings or foam or cant strips. You are the polyurea guy and you disagreed. I have seen polyurea work in the condition i described above. since you argued I couldnt help but think you had a bad experience with these types of applications using polyurea. Reinforced polyurea has been tested to withstand an explosive blast. If this technology was brought into the roofing industry… God only knows the possibilities. As i Have said, Im a big fan of Polyurea . The difference between acrylics and polyurea is that acrylics can be applied when water is actually present. Not puddles but a visibly moist surface. I can bury you with evidence supporting my statements. Before you try to insult my intelligence again maybe you should take some of your own advice. please![/quote]