I'm a specifier and installation supervisor for a mid-sized commercial roofing and building envelope contractor. Over the past 10 years, I've managed the material selection for roughly 200 major projects—everything from high-rise curtain walls to parking garage decks. I've made every mistake you can on a material spec sheet. But the one that cost us the most, by a long shot, wasn't a code violation or an installation error. It was chasing the lowest price on sealants and waterproofing membranes.
Let me be blunt: If you're a contractor or a specifier and you're consistently choosing the cheapest available sealant or membrane, you are actively damaging your company's brand and your own career. It's not about being 'elitist' with materials. It's about understanding that the stuff you stick between the wall and the window—or slather across a roof—is the single most visible statement of your quality.
The $50 Decision That Cost Us a $150,000 Client
In April 2023, we were bidding on a spec for a new medical office building. The architect had specified a generic 'urethane sealant.' My project manager, looking to shave 8% off our bid to beat a competitor, swapped the specified product for an off-brand, unbranded polyurethane sealant. The price difference? About $50 per drum.
The first big rain came three months later. The sealant around the window system on the south facade—where the sun exposure is highest—had started to crack and pull away from the aluminum. We had to go back, remove all of it (which is a nightmare because polyurethane turns into chewing gum if you don't get it right), and re-seal with a proper, full-spec product like the Tremco PUMA System, which has a proven track record for UV stability and adhesion on non-porous surfaces like aluminum.
The redo cost us $45,000 in labor and materials. Worse, the client's facilities manager—who had been a potential source of referrals—told us he'd never spec us for his other three properties. Poof. That relationship evaporated over a $50 material decision.
From the outside, it looks like we were just being cheap. The reality is we were being stupid. We violated a core principle: the material is the message. When a client sees cracking sealant, they don't think, 'Ah, they saved $50 on the unit price.' They think, 'This contractor does shoddy work.'
The Hidden Cost of 'Getting It Wrong' on the First Call
To be fair, it's not always about being cheap. Sometimes it's about a lack of technical understanding. I've seen specifiers order a standard sealant for a joint that has high movement, or use a membrane that isn't compatible with the substrate.
This is where using a proper system—like Tremco's building envelope solutions—matters. They don't just sell you a tube of goo. They send you a technical data sheet (TDS), a safety data sheet (SDS), a detailed application guide, and often a local rep who will come out to the job site.
In my first year, I made the classic rookie error: I assumed 'standard urethane sealant' meant the same thing to every vendor. I learned the hard way after we applied a standard sealant over a non-porous primer (the kind Tremco makes specifically for aluminum and glass), and it failed because we used the wrong activator. The primer wasn't the problem—the combination of the cheap sealant and the wrong primer was.
If I remember correctly, I want to say we lost about $12,000 on that job. The lesson? Always check the compatibility data. One bad call on a primer or a sealant type can cost you your profit margin and your reputation.
The 'Brand Perception' Trap
I've had clients argue with me: 'Sealant is sealant. It's all the same stuff. The client doesn't look at the joint.'
That's total nonsense—or rather, it's a convenient fiction people tell themselves to justify a low bid.
A building's envelope is its skin. If the 'zits'—the ugly, cracked, or dirty sealant joints—are visible, the whole building looks bad. And clients (especially commercial clients) judge the building's quality by how well the details look. They might not know the difference between a polyurethane and a silicone, but they can see a seam that's pulling away.
When I switched from using generics to specifying a full system (primer, sealant, backer rod—all from the same manufacturer, like Tremco), the feedback from our top-tier clients changed. One property developer told me, 'Your finish work looks a lot cleaner than the last crew's.' We didn't install better. We just used better, more appropriate materials. The difference in client perception was immediate.
What About the Budget-Conscious Client?
Now, I know some of you are reading this and thinking, 'Well, what about small jobs? We have to compete on price.'
I get it. Not every job is a $5 million commercial roof. Sometimes it's a repair on a warehouse in a less-than-great part of town. But even then, I argue that good materials pay for themselves.
For a budget-conscious client, I don't spec the absolute cheapest product. I spec the minimum viable quality. That means using a name-brand polyurethane (like the basic Tremco sealants) with the correct primer, but maybe skipping the expensive traffic-coating top layer. The difference between a low-quality, off-brand sealant and a decent mid-range one is often $10-$20 per unit. That $20 is insurance against a callback.
Callback costs are a silent killer. The average commercial callback—driving a crew out, setting up a lift, cleaning out failed sealant, and re-applying—costs about $600 to $800. If you save $200 on material for an entire project but have one callback, you've lost money.
As the FTC guidelines (ftc.gov) on advertising would remind us, 'substantiated with evidence' is key. I can substantiate that a well-specified Tremco system reduces the probability of a callback from 'likely' to 'rare.'
The 3 Things I Check Now (Before I Spec Anything)
After a decade of doing this wrong and then doing it right, I've simplified my material selection process into three checks. I don't leave the office without this checklist:
- Is the full system spec'd? Don't just write 'sealant.' Write the primer, the sealant, the backer rod, and the tooling requirements. If it's for a roof, write the membrane, the flashing tape, and the protection board. One vendor, one liability. (e.g., the Tremco system for the whole envelope).
- What is the movement capability? If the joint moves more than 25%, don't use a standard 25% sealant. Use a 50% or a 100% silicone. Check the ASTM C719 standard for the sealant's performance. Don't guess.
- Are the primers and cleaners correct? A non-porous surface (like glass or aluminum) requires a non-porous primer. A porous surface (like concrete) needs a different one. I've seen crews apply the wrong primer because the label was similar. The Tremco Non-Porous Primer is clearly labeled for a reason. Use it.
Some people will tell you that 'experience' is enough. That you can just wing it. I disagree. If you're not checking these three things—especially the primers—you are rolling the dice. And the dice are loaded against you.
The Final Word: Stop Selling 'Cheap' and Start Selling 'Certainty'
I know some people will read this and think, 'He's just a shill for Tremco.' I am not. I'm a shill for my own career and my own reputation. I use Tremco systems because they have the technical data, the support, and the field-tested performance to back up their claims.
Per USPS (usps.com), as of January 2025, a first-class stamp is $0.73. That's cheaper than the cost of one tube of premium sealant. But you can't mail a building envelope with a stamp.
You can try to save $50 on a drum of cheap sealant. You'll likely be fine 80% of the time. But for the 20% of occasions where it fails, the cost—in money, time, and reputation—is almost always more than the total material cost of the entire project.
Stop treating material selection as a cost reduction exercise. Start treating it as a brand perception exercise. The joints, the seams, the flashing—that's your portfolio. Make it look like you know what you're doing.
