Commercial Roof Clean, Large High School


General contractor/project manager



Only 360,000 sq ft to go! Haha


Why is it black and white? Can you post a close up shot?
Are you taking the black off?


great question, the EPDM is the black and my best guess is the white was a primer or some kind of sealant they had put on in the past. The contractor is not for sure what it is exactly but the scope only requires to do chemical application and remove the top layer of film from membrane. They are not expecting all the “primer” to come up but have mentioned that if it peels up when pressure washing just go with it. Had some concerns with that but narrowed it down in contract. Hardest part about this job is the 240 A/C units :tired_face:



thanks for the reply



Finally finished up this project last Tuesday, for sure learned my fair share of lessons, do’s, don’ts, and everything in between. Month long project completed though and thankful I took it on. The brilliant white section on the right side is the finished portion that the roofing company has completed with the elastimeric coating after I had cleaned. Simple process overall but had to be very thorough and meet many mandatory walk thrus and wipe test with manufacturer of cleaning product and GC. On the seperate building you may notice what look like your standard “striping” when using a surface cleaner, this is the roofing membrane seams, it doesn’t look it but that building is about 185’ wide.


I did commercial roofing in florida for 4 years. I pressure washed many roofs just like this for a company. We would then go back and seal them with a waterproofing after they were cleaned. Good times.


GREAT JOB Chris!!!


So how did you end up cleaning them?


Ended up trying a few different methods, the main roof was a EPDM rubber material that had alot of carbon buildup on it. For that membrane we applied GacoWash (pricey degreaser) let sit and surface cleaned and broomed any places that needed to be aggitated. I let the GC know with the age of a material and the type it would never not have some black coming off but the goal was to get it to where primer would stick. They were happy with the results of the surface cleaner but I had to keep the PSI right at about 3,000-3,600 otherwise I would have to go back over it as it wouldn’t all come up. With the TPO is was much “easier”, 3 medium bristle push brooms, wait for a overcast day with some rain, spray the chemical on and let it sit for about 10 min, brush and then rinse with PW. Very nice effect, great service to offer as post commercial construction as many trades are still up on the roof til the very end and the GC has to leave the roof looking good for final product. Trying to put together a package service now for projects like that.


ALSO, this roof was LITTERED with holes when I showed up. Myself and my guys did a very thorough walkthru before and marked all holes and sent pictures to GC for liability purposes. It was also clearly stated in my contract I was not to be held responsible. That was the big one for me since we were using the surface cleaners but it would not have gotten clean without them. And I wasn’t about to wand 400k sq ft.


Did you do the waterproofing as well or was that a service you brought on after doing a few?


Was there any reclaiming involved?


No sir, sanitary sewer from the roof drains. Had to block all scuppers though on the roof as so there wouldn’t be black drainage on the walls. Biggest part of cleanup was dealing with all the white flakes from the primer that was on there from years before, just had to bag it.


Sounds awesome, glad it all worked out for you.

One month? …did it pay as goood as doin a month of residential?

I don’t expect you to tell your price on here but maybe a ball park figure?

$ 10,000 - $ 20,000?

20,000 - 30,000?


It exceeded my expectations for sure with being my first large scale job. Side by side comparison of residential vs month of commercial the payout was way better, the number I put on the job was close to $40,000. Obviously doesn’t include any expenses labor, hotels, meals, equipment, insurance, etc. There was plenty of expenses but honestly if I would have taken home even what I typically make on a month of residential I would have felt great about it because it gave me alot of confidence in taking on future jobs and how to be better prepared. I would say hands down the hardest part of the job is that it was out of town and being away from my wife and daughter, but that where sacrifice for the family came into play.


Thanks for all the info. Good post.


No problem, this job taught me quite a bit. Great learning lesson on my behalf but feel good to walk away after lol. Jobs that long will get to ya