Is my new modified bitumen roof installed correctly?

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My new roof was installed last week. I had a 400 sq. foot section of flat roof that was supposed to receive modified bitumen. I wanted to add a bit of pitch but the estimator/project manager pushed back on that idea because he said the cost of framing would be exorbitant. All I really wanted was a couple of inches to eliminate the ponding so I asked about tapered insulation. He had never heard of it but asked his guy, came back with a reasonable price, and I approved it and signed the deal.

Well, when they showed up they came with standard 1/2 inch foam board from Lowe’s. I shot that down immediately and made them try to find tapered insulation like I wanted while they seemed to have not ever heard of this product and insinuated it was some exotic material largely of my own imagining. (I replied, “Go on Google, search for “tapered insulation”, and you will find it is manufactured by Owens Corning, GAF, Firestone, Johns Manville, etc.”) Well, the price came back as “expensive” (I didn’t ask) and the owner offered to frame out some pitch for the same price as the original agreement. As that was all I wanted in the first place, I agreed.

After the crew left, I went up to inspect my new “modified bitumen” roof membrane and found something that does not look like any modified bitumen membrane I am used to seeing. I have always seen cap sheets that pretty much resemble three tab or laminated/architectural shingles in texture and rigidity. This is almost smooth, with a very fine grain, and is very soft. It’s squishy and you can’t touch it when the sun is on it without leaving a mark.

As far as the roofing company is concerned, they are done. If this is a base sheet, they have no plans of coming back to put a cap sheet on. There are also some installation quality issues. I’m trying to get another company out here for an opinion but am curious what you folks think.

Thank you for your time.

I’m pretty confident that’s Owens Cornings Ice and Water sheild self-adhered “underlayment.”

It now needs some "cap sheet"
That roofs not done.

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I noticed it isn’t in the pictures but there are sections of seams where you do see cement seeping out so I was thinking a cold-applied material. I saw some Tamko rolls on-site when they were working but didn’t take note of the product. It sure doesn’t look like any cap sheets on the Tamko web site. It looks like their glass base product but I’ve never been hands-on with these materials so can’t say for sure. There is self-adhered ice & water shield under this.

Too many issues here… Not sure where to start…

You ‘might’ have a layer of modified base sheet somehow loosely attached, but you in no way have a modified roof system installed. This ranks up there in the top ten worst DIY roofing disasters I’ve seen in a while. Why did you hire this person if they weren’t even familiar with the products and materials you wanted installed? Did they have any credible references?

  • Wrong materials
  • Incompetitent installer
  • Improper / inadequate adhesion
  • Loose seams / laps
  • No terminations
  • Penetrations not flashed properly (gooped on cement? Come on man…)
  • From your description, inadequate slope / drainage
  • Missing a cap sheet / surfacing
  • Wrinkles and voids in the laps
  • Missing edge metal
  • Absolutely nothing detailed correctly

I’ve seen blue tarps nailed to plywood that are in better shape then this. Be thankful that it’s only 4 SQ and they did such a poor job installing it that removing it should be pretty fast and easy.

It’s a family-owned roofing contractor that has been operating for over ten years in the area. They’ve won customer satisfaction surveys in the local newspaper for several years in a row. They showed me a project they completed in my neighborhood on a house far more expensive than mine with a modified bitumen flat roof. I checked out that roof as well as one can from the ground and the modified bitumen looks exactly as I expected it to. I chalked up the unfamiliarity with tapered insulation to their being a residential-only contractor. And the owners are friends of my wife. I thought I was doing well in vetting matters. There was no haggling over price, either. I just told them what I wanted and accepted their number.

I watched the shingled sections go on and was satisfied with that work. Then they came back to do the “modified bitumen” while I was out and when I checked on it after work I discovered this nonsense. Thinking it might be temporary, I gave it a few days to see if they’d come to finish and then called the office to determine if they were done as far as they were concerned and they said they are. That’s when I started documenting, researching, and contacting professionals for their opinions. I hope to have someone from another company here tomorrow.

Well, the company I had on the line to come give an opinion doesn’t want to “get involved” and is telling me I’ll have to contact the original contractor. But how is a layman supposed to develop an informed line of argument to use with the original contractor if no other contractors will weigh in?

It’s not large enough to hire an independent consultant. Frankly, I would just find a new contractor and simply get a quote to have the roof replaced- unfortunately that’s what you’ll have to do sooner or later.

Where in the country are you located? There may be an off chance I can put you in touch with a commercial roof inspector. Based on you saying Tamko materials were used I would imsgine you’re in the center of country.

Have you considered contacting a home inspector or even an insurance agent?

Location is southwest Tennessee. Hadn’t thought about insurance or a home inspector. I’d guess my homeowner’s company would be pretty interested in this. Thanks for the ideas.

I would set an appointment withy the owner so you can show him that the cap sheet is not installed.
The granules should be the same size as the ones on your shingles.
There should be no drawn lines on any cap sheet.
That is Underlayment!!!
Really really nice underlayment.
But I still believe it needs it’s cap sheet.
The amount of money to finish your job is around 500. You just need 4-5 more rolls.
Plus labor.
It should stick well to that material.
Certainteed, Gaf or Polyglass.
I would go with Certainteed.

Looks like ply 4 to me. Agree with everyone else, not finished.

It’s been two weeks since my new roof was installed and I’ve put together a lovely album of its current state:

In the meantime, I’ve visited the contractor’s office to have them tell me the membrane used here is Firestone SBS Smooth and that it is not merely acceptable as a cap sheet but is a superior product to the granuled cap sheets with which I am familiar. (When I mentioned to the project manager that I had never seen a smooth surfaced cap sheet, he replied, “And how long have you been in the roofing business?” This was one of the guys who looked at me like I had three heads when I started talking about tapered insulation.) While they were showing me the Firestone SBS Smooth in the warehouse, I could not help but notice the Firestone SBS Cap in ultrawhite sitting not a foot away from it. This makes it difficult for me to chalk this up to simple ignorance/incompetence at this point.

I’ve talked to Firestone technical support and they confirmed SBS Smooth is not intended to be a cap sheet and corroborated my understanding that modified bit should have some kind of positive slope and not pond. (At least not more than a small amount for a few hours.) They put me in touch with the distributor for my area so maybe I can get a recommendation for someone competent to take on correcting this.

Ok, he’s right!
You can have a granulated cap sheet or a smooth cap sheet.
So when is he coming to paint the roof and finish the job.?
Either you get granules on your product to protect what’s underneath or paint.

I started out using smooth only for years
Because I believe it is the better product and that it adheres better than granulated.
It’s true.
I just got tired of having to convince my
Customers that they needed to keep it painted and how often.
So now I only use granulated.

But what concerns me is that true smooth modified should never get foot prints in hot weather!!!
That’s what underlayment does!!!

I wonder why there are lap marks on the top of the sheet. That should be the selvage edge that is covered.
I don’t care what they told you, that plumbing vent is wrong. You shouldn’t be able to pick up the lead edge like that. If I remember, the smooth rubberoid I used in the 90’s only came in STA. It was not a cold process system. That would mean they would have had to hot mop this stuff or torch it. I don’t know many companies that use modifieds anymore. So many better products on the market.

I agree with others, bad job. Looks pretty now, but pretty doesn’t keep water out. Mastic over nails or nail pops on a mod roof?

Ok , ok
If that is cold process
And there is truely ice and water throughout And with a layer of modified bitumen asphalt(tar)
Between the two layers…
I’ve never done it that way but that would work.
You could leave it and possibly get 15 years or more out of it.
Maybe, I don’t know.
But I would paint it.
I really don’t think that particular product has any warranty.
I don’t think it is meant to sit in the exposed son without paint or something with real granules on it.

I think you should go ahead and paint it yourself.
He doesn’t want to do it.
Paint it with aluminum roof coating.
Fibered first and then unfibered.
2 - 5 gallon buckets.
About 100-130 bucks.
Mix well!

Update: Thanks to everyone for your help. After presenting my evidence and claims to the contractor, they have conceded. I’ve arranged a meeting with another contractor that does more commercial work to discuss options and get a quote.

The original contractor sent me an invoice for the balance on the project minus the faulty work and the work yet to be done, i.e. gutters. I’d like to wait until the project is complete before considering what to do on that point as it seems my property is at risk from the faulty installation and could incur damage related thereto in the time intervening.

I took some pictures of damaged shingles on the “good” part of the roof. This is the area most frequently trod on to gain access to work on the flat part and there seem to be way more areas where the granules were scraped off than I consider reasonable for a “new” roof:

I’m weighing whether to ask the new contractor to replace those shingles as part of the next project and to debit that work from the original contractor’s invoice.

After having been in the sun/rain for coming up on three weeks (and counting), this membrane is toast and will have to be replaced. The “slope” they added is also inadequate and exhibits bad ponding, in one location even worse than before the “slope” was added.

Your thoughts/advice/wisdom are, again, appreciated.

Those shingles are plenty beat up and should be swapped out. Get the flat roof replaced first, as more damage might be inevitable. Looks like a pretty minor repair, unless it’s more extensive than it appears.