EPDM question

Hey all, I have a question and your now in my shoes..... Your have a church with a Carlisle .045 mil roof system installed in 1990. The field rubber still looks good and there is only 1 leak in the maybe 80 sq. roof... You are asked to come in and patch the roof...

Now the fun part, sometime in the last 4 years, another contractor sold the church on some preventative maintenance work and resealed ALL of the existing seam... with good old asphaltic mastic and fiber mesh... yep, roof cement... Then 4 months ago, they can back and applied a real heavy coating of Home Depot roof cement to 6 seams ( within a 10 ft radius ) of the leak... Real messy to !!!

So, what approach do I offer them to fix this leak...

Option # 1 - scrape off the roof cement and try to clean it so that the rubber peel and stick will work... Which will be really tough... and time consuming.

Option # 2 - ( which means tossing out everything I was taught ) scrape the messy old roof cement, clean up rough surfaces and apply a Karnack Modified cement and 2 layers of polyester mating patch to these ( already messed up ) areas.

Even if I can get the church water tight for a couple more years, they will be happy with that, and they fully understand what was done wrong, and KNOW this is a temporary fix...

Your thoughts...

Hey guys, thanks for your input. It was my first time posting here and I listened to everyone's answers.....

I thought about cutting out the troubled area and applying new, but once I cut into the roof, I own it... so I was NOT taking that liablity.

The idea of applying an EPDM patch over the asphalt mess, was really involved and I still would not be able to have a tight seal, as the asphalt mess was all over the place...( It was spread on all of the perimeter flashings, the 4 foot back anchors around the perimeter and on all seams ), so.... a mess.

I finally went with the option of cleaning off as much as I could, then applying a 6. 9, & 12 inch strip flashing to the problems seam, using Kanank # 66 and polymat. It went down well, but time will tell how long it stays down.. The church FULLY understands what may happen and they agreed with this approach so time will tell...

( My grandfather is rolling in his grave about this repair ! )

Again thank you gentlemen...

Must be an echo in here..echo in here....echo in here!

Use a piece of epdm over existing repairs glued to the field with seam tape. option 2 i'll try it out tomorrow.spray dry ice and see if it can help peel the roof cement off epdm.

The existing serrvice life of the EPDM has pretty-much expired, as well as being damaged via the bituminious cements.... Obviously the church must not have the $ to replace it, as it should be....Once in a while we run across similar situations...A lot of times I'll just send a repairman out for a half-day or so, to make, (in this case). make-shift repairs, give them a proposal to re-roof and consider the 4-6 manhours as an investment towards a future project....If not, I just chalk it up to my, "do a good turn daily"....

I can hardly believe this is coming out of my fingertips, but here goes.....

The church needs a couple years. 45 mil non-R rubber, it's likely to start pinholing anytime. Every dollar you spend on it, is money down the drain.

If you scrape off the cement, I think the oils will have damaged the epdm to the point that PS flashing material may not adhere anyway, and then you're back to square one with wasted money on two efforts.

Patch the hole, leave the cement, unless it's causing it to fishmouth/wave so badly that failure is imminent. If the cement/mesh combo is doing OK for the time being, maintain it, and make sure the church KNOWS - Never do this again.

The less money you spend on it now, the sooner they can afford to get rid of the liability and fix it right.

Ditto. Temp patch? Just cover and seam tape it.

45 mil rubber and 20 years old! You are going to scrub right thru the rubber! You may be better off cleaning the area around it and installing a section of rubber right over it and then seal the outside seams to the rubber with the seam tape and cover tape! Just a thought!