Ripples in Rubber Roofing?

I did an inspection of a condo in a big complex today. Brand new building built in 2007. I don’t do too many inspections of rubber roofs around here. The roof had several ripples in it. See pic for example. Is this poor installation, or is it pretty normal. How would you write up this condition in the report? Deficient or serviceable. Thanks in advance for any help.

Main St., Waltham 004.jpg

It just hasn’t been pulled tight or rolled out properly to take the wrinkles out.
Will it affect performance? No, not unless the roof is walked on or used as a deck and someone happens to catch the wrinkle and rip it.

I don’t write up minor ripples at the edges, as not many roofers’ are perfect. What you’re inspecting for is tightness to the underlying surface with no major air pockets throughout the field. If I observe big air pockets, I write it up for repair. All rubber should be securely glued down…Period.

Also, check every seam for gaps. If seams are becoming loose, water will seep into this area and cause major problems.

Another major issue I usually find in rubber roofs is drainage problems. Write up any major puddling.

Here’a a great guide on Rubber Roof installation…


Good advise David.

Your rubber roof here looks as if it is used as a deck area. If so those ripples area trip hazards by the railing. Yes, not all roofers area perfect, but in areas such as this they need to be. They can be sloppy else where.

If so, that is an issue.
No walking on rubber roofing.

Ripples in any roofing material are the first point of deterioration from the sun in Arizona, but I don’t know about other areas of the country.

Any flat roof I’ve inspected with any type of material, if there are ridges, ripples, they are deteriorated MUCH more than the rest of the material, so if I see ripples on a flat roof generally it is not cost effective to repair them, I simply tell my client to expect those areas to fail at a faster rate than the rest of the material, and replacement will need to done at a premature age of the material.

i don’t think all rubber roofing is fully adhered. some is mech fastened, some ballasted.
i don’t think the minor ripples need to be called out. it may not even be a roofing application problem. the building could have moved since the roof application.

seams, punctures and flashing are usually the problem areas.

EPDM roofs can be installed in a variety of ways, and the most commen is the fully adhered.

Some of the Inspections of the EPDM roofs as done by most Building Maintenance people would be as listed below.

EPDM Inspection Insights
When inspecting an existing EPDM roof system, roofing consultants, maintenance and engineering managers and other individuals responsible for a building’s maintenance and performance should look for these conditions:

  • disbondment at seams, laps and splice areas, which can result from poor workmanship, delamination, physical damage and deterioration over time

  • holes or punctures in membranes as a result of fasteners backing out of substrates or contact with heavy objects

  • wrinkles in the membrane that restrict water flow, caused by inadequate attachment, curling of insulation or contraction of the membrane after application

  • shrinkage of sheet membranes

  • dimensional stability of the insulation that deforms or otherwise puts undue stress on the membrane

  • defects in ballast, such as broken, deteriorated or missing pavers, exposed membrane due to displaced ballast, or ballast with sharp edges

  • defective or improper repairs in the roof membrane

  • improper application of EPDM sheets that were not allowed to relax, or recapture themselves, before perimeter securement

Workers can repair many of these defects by cleaning the membrane thoroughly and using tape products recommended by the manufacturer. Workers using any adhesive product on an EPDM membrane should completely clean the area where the adhesion will occur. Dust and dirt reduce the ability of tape to adhere to the membrane, making it possible for the repair to peel up and allow water into the substrate or insulation.

It is also important to trim or cut the edges of the EPDM patch so the splice or patch is slightly rounded, thereby leaving no sharp edges to peel back and disbond.

Marcel :slight_smile: :slight_smile:

I’m in agreement with Dale and Marcel. I’d write it up, if for no other reason then for the fact that the sun will deteriorate the surface here faster. That ol’ Mis’sip’i sun is about as bad as the one in Arizona! Also, look carefully at the drainage associated with this particular area. If it retards drainage or causes pooling here, that is an issue.

Thats strange I would have thought a EPDM membrane would have UV stabilizers in the material to prevent membrane breakdown fwiw.

It is extremely resistant to the elements of outdoor exposure, (Sunlight/ UV exposure, Water / Moisture and the Temperature extremes associated with worldwide climates).

Simply note any inconsistencies (ripples) and move on. In my book…small ripples aren’t no big deal.

I agree with that statement also.

Marcel :slight_smile:

I agree with David Valley and Marcel Cyr that small ripples aren’t a big deal. I have been a Project Supt. in commercial and industrial construction for over twenty years and have used EPDM on many projects. As long as water flow is not restricted or has little restriction, it should not pose a problem as long as the seams and roof penetrations are properly sealed.


Welcome to iNACHI. You just dug this post up from last years threads.

You must be doing your research.

Big problem here in Philly that I have run across is they install rubber roofing and do not allow for it to relax. The rolls are not stored or transported properly and get flattened out. The contractors I have seen just glue it down with the ripples in it. You can tell what side of the roof the worked to and from by the spacing in the ripples as they rolled out the rubber.