Performance vs. Warranty: What NDL Actually Means and Why the Lowest-Cost System Isn’t Always the Answer

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Q: What does NDL mean in a commercial roofing warranty?
A: NDL stands for No Dollar Limit. It means the manufacturer does not cap the dollar amount of covered repairs under the warranty. NDL does not mean all damage is covered, that consequential damages are included, or that pre-existing conditions are the manufacturer's responsibility. A restoration coating warranty covers the coating system itself — not the underlying roof assembly or conditions that existed before the coating was applied. If pre-existing moisture or structural issues cause a failure, that claim will typically be denied. NDL is a trademark concept originally associated with Johns Manville and is widely misunderstood in the commercial roofing market.

 A friend of Jani Bryson’s put a silicone coating on her roof. She was told it came with a lifetime warranty. She never had to think about that roof again. It was covered. Everything was covered.

It is not covered. Not even close.

What NDL actually means

NDL — No Dollar Limit — is a term that gets repeated constantly in the commercial roofing space, often by people who don’t understand what it means. John McDermott addressed this directly on Episode 1 of Roof Riffs: NDL is a trademark concept originally associated with Johns Manville. All it means is that the warranty doesn’t cap the dollar amount of what the manufacturer has to do if there’s a covered problem. That’s all it means.

It has nothing to do with consequential damages. It has nothing to do with coverage for underlying conditions. It does not mean everything is covered. A restoration coating warranty does not cover the original roofing system beneath it, or the conditions that existed before the coating was applied. If there’s a pre-existing problem under the coating that causes a failure, that is not a covered warranty claim.

Where this goes wrong

John and Danny both identified the same source of confusion: the residential roofing market. As more residential contractors have entered the commercial space, the warranty-first sales mentality has come with them. Homeowners are accustomed to the idea that a roofing warranty covers everything. Commercial restoration coatings don’t work that way, but the sales language has leaked across.

The result is building owners who believe they have more protection than they do, and contractors who are selling warranties they can’t back up with performance.

The lowest-cost system

John made a point that doesn’t get said enough: the lowest-cost coating system may not be the best system for a given application. Karnak makes a low-cost system in certain categories, and John will tell you directly it’s not their best option. Price is not a proxy for performance, and contractors who are new to the commercial restoration space sometimes default to the cheapest option and sell it as though it’s equivalent to higher-performing systems. It isn’t.

The guidance from both John and Danny is the same: do your due diligence. Hire a credible contractor. Work with a manufacturer that has real history in the industry. And choose the system that’s right for the substrate and the application, not the one with the biggest warranty number on the label.

Division 7 Sales helps contractors and building owners understand what coating systems are actually right for a given roof — before the purchase order goes in. Visit division7sales.com to connect with someone who will give you a straight answer about performance, not just a warranty number.

Hear the full warranty and performance discussion on Episode 1 of Roof Riffs.