Most people outside the fireproofing industry think fireproofing is simply "spraying something on steel." Anyone who's actually estimated both cementitious and intumescent systems knows that's nowhere close to reality.
While both products are designed to protect structural steel during a fire, the similarities largely end there. The materials behave differently, they're installed differently, they're inspected differently, and perhaps most importantly for estimators, they're bid differently. Treating an intumescent project like a cementitious project (or vice versa) can quickly turn a profitable job into one that loses money.
Cementitious fireproofing has been the workhorse of commercial construction for decades. You'll find it in hospitals, schools, office buildings, warehouses, parking structures, and countless other commercial projects.
From an estimating perspective, cementitious systems are generally straightforward. Once you've determined the required hourly rating, UL design, and W/D ratio, the takeoff becomes a matter of accurately identifying the steel members and applying the correct assemblies. The challenge isn't usually understanding the material. It's making sure every beam, joist, column, and deck condition has been accounted for correctly.
Experienced estimators spend a significant amount of time reviewing structural drawings before they ever begin counting. One missed framing revision or overlooked specification can easily affect hundreds of pieces of steel throughout the project. Production rates also tend to be predictable. Installation crews can often cover large areas quickly, making labor calculations more consistent from project to project.
Intumescent fireproofing changes nearly every assumption an estimator makes. Instead of a spray-applied cementitious product, you're dealing with a high-performance coating system that expands when exposed to extreme heat. These systems are frequently selected because the structural steel will remain exposed as part of the building's architectural design.
That changes everything. Instead of simply calculating fireproofing quantities, estimators must begin thinking much more like a painting estimator. Surface preparation becomes a major cost factor.
On many projects, labor, not material, becomes the biggest variable.
One of the biggest mistakes newer estimators make is assuming the structural drawings contain everything they need. Which the most certainly don't! The specifications often contain critical information regarding acceptable primers, approved manufacturers, required dry film thickness, inspection procedures, and coating systems.
Some projects specify a single manufacturer's complete coating system. Others allow approved equals. Some require shop-applied primers while others require field preparation before application. Those details may seem small, but they can dramatically change both labor hours and material costs.
Intumescent projects almost always involve steel that people will actually see, that means appearance matters. Unlike cementitious fireproofing, where the finished product is typically concealed above ceilings or inside wall assemblies, exposed structural steel is part of the finished architecture. Every connection, weld, stiffener plate, clip angle, and complicated beam intersection takes additional time to coat properly.
Estimators who rely only on beam lengths without considering the complexity of the steel often underestimate labor requirements. Sometimes two projects contain nearly identical quantities of structural steel, yet one requires substantially more labor simply because of the architectural detailing.
Inspection is another area where these two systems differ.
If those inspection requirements require additional mobilizations or schedule impacts, they should be considered during estimating rather than discovered after the project has started.
Software has dramatically improved the speed and accuracy of fireproofing takeoffs, but no software replaces estimator judgment. Knowing how to interpret a UL assembly, recognizing unusual framing conditions, identifying specification conflicts, or anticipating installation challenges still comes from experience.
The best estimators aren't simply measuring steel. They're evaluating how that steel will actually be fireproofed in the field. That's the difference between producing accurate quantities and producing an accurate bid.
BuzzBID's new FireShield software combines our fast and accurate ClickONCE™ Computer Vision assisted takeoff with full-featured fireproofing estimating functionality to improve your productivity and accuracy.
Whether you're estimating cementitious spray fireproofing or an intumescent coating system, success begins long before the first quantity is measured. Understanding the specifications, reviewing the structural drawings carefully, recognizing architectural conditions, and anticipating installation challenges all contribute to a more accurate estimate.
The materials may serve the same purpose, protecting structural steel during a fire, but from an estimator's perspective, they are two very different projects. The more you understand those differences before the takeoff begins, the more confidence you'll have when it's time to submit your bid.