This is a common question after a water damage. The answer, as the extent of the water damage often shows, is: NO! Why not? The sealants seen around penetrations (piping, cables, etc.) are fire stop sealants… NOT water stop ones!
What is a Fire Stop?
The Quebec Construction Code, Chapter 1 – Building requirements are that:
3.1.9.1.1) [..] penetrations of a fire separation or a membrane forming part of an assembly required to have a fire-resistance rating shall be:
a) sealed by a fire stop that, when subjected to the fire test method in CAN/ULC-S115, “Fire Tests of Firestop Systems,” has an F rating not less than the fire-protection rating required for closures in the fire separation […]
Other configurations (garages, horizontal service spaces, etc.) require an “FT rating” according to the same Code. Still others, such as sprinkler piping, benefit from some exemptions.
The same Code also defines:
Fire stop means a system consisting of a material, component and means of support used to fill gaps between fire separations or between fire separations and other assemblies, or used around items that wholly or partially penetrate a fire separation.
The F and FT Ratings
The CAN/ULC-S115 standard explains that:
An F rating is based upon flame occurrence on the unexposed surface.
An FT rating is based upon temperature rise criteria as well as flame occurrence on the unexposed surface.
Frequently Used Products
The two (2) products most often seen as part of a fire stop system around penetrations are:
- caulking, most often red-coloured, and
- collars.
Other available products include wraps, pillows, bricks, plates, plugs…
Most of these products work on the principle of intumescence: that is, they expand when exposed to fire. In other words, they do not necessarily occupy all the available space around the penetration as long as they are not exposed to fire. Therefore, they are not watertight.
It also bears repeating that it is not the product itself that has the F or FT rating, but rather the system consisting of material, component, and support; approved together as a system, according to CAN/ULC-S115.
UL 1479 Fire Tests of Penetration Firestops is an “American equivalent” to CAN/ULC-S115. This Standard includes a W rating, for “water”: the W rating is based on the water resistance of the tested sample.
To obtain a W rating according to this Standard, the test sample shall withstand a water pressure of at least 3 feet (1.3 psig) for at least 72 hours within the water leakage test chamber.
So … Are W Ratings the Future?
Currently, there are no regulatory requirements for the W rating on our side of the border. Perhaps there will be in the future?
However, certified fire stop systems already exist that also have a W rating. It could be pertinent for design engineers to require their use in areas at higher risk of water damage: for example, a mechanical room at the top of a high-rise building. This choice, coupled with a consistent design strategy, could limit the extent of an eventual water damage.
Okay, But … Is It Normal If There Is Nothing at All?
An analysis will be required to determine if this is normal or not. The CAN-ULC-S115 (then CAN4‑S115) has existed since 1985. It is required in some configurations since the National Building Code of Canada 1990.
