Specified Technologies, Inc. fills industry need

Editor’s Note: Last year Vincent Ciernick of A1 Central Vacuum Inc. contacted Specified Technologies, Inc.

(STI) Fire Stop Products about making a fire stop product specifically for the central vacuum industry. Ciernick sent STI 60 feet of ASTM vacuum pipe for fire testing. Working with Ray Bruno, vice-president of marketing and sales, and James P. Stahl, Jr., director of technical services, STI was proud to début this product at the VDTA Las Vegas Convention. This specially made fire stop kit for the industry will be a great success. It will be available through your central vacuum manufacturer or from major distributors worldwide.

We often see the power unit/collection canister for a central vacuum system installed in the attached garage in single-family residences. Dependent upon the local code in effect, the wall/ceiling separating the garage from the living space may be required to provide a measure of fire resistance. The opening made in the wall/ceiling to accommodate the tubing can be an area through which fire can spread unchecked if it isn’t properly sealed. When the central vacuum system is installed in new construction, there have been situations where the authority having jurisdiction (AHJ) has discovered unsealed penetrations by vacuum system tubing and this has delayed issuance of the certificate of occupancy. Fortunately, firestopping systems have been developed with these types of applications in mind.

Any time a power unit/collection canister is going to be installed in an attached garage/basement, it is important to determine whether there are fire resistance requirements to consider. If the central vacuum system is being installed in an existing home, it may be desirable to err on the conservative side and assume that there are fire resistance requirements involved. This will protect lives, property and your liability in the event that a fire occurs.

Sealing tubing penetrations is pretty straightforward. Metal vacuum tubing is relatively benign. The use of standard fire stop caulk, which is readily available in the market place, is the most suitable product. An example of firestop caulk is SpecSeal® Series SSS Sealant or Series LCI Sealant manufactured by Specified Technologies Inc. Although metal tubing is inherently fire resistant, care should be exercised to prevent putting a short section of metal tubing through the wall followed by connections of PVC tubing on either side. In this scenario, the PVC tubing can melt and the fire can still spread through the wall via the interior of the metal “stub” of tubing. In the firestopping industry, this scenario is called the “chimney effect” and it should be avoided. Your local code may require you to run metal pipe from the firewall all the way to the unit, which is expensive in material and labor.

Plastic tubing formed from PVC can be safely fire protected where it breeches a wall with fire resistant requirements. Typically, a firestop wrap strip or a firestop device known as a firestop collar is recommended. Firestop wrap strips are thin, rubbery strips of material impregnated with intumescent material. Intumescence is a phenomenon that occurs when the material is exposed to high heat and flames, it expands volumetrically to squeeze off burning or melting combustibles such as plastic pipe. Firestop wrap strips can be encircled around a pipe, secured with aluminum foil tape, and slid into the hole around the pipe, also known as the annulus, such that the exposed edge projects 1/4 in. from the wall surface. The remaining space between the wrap strip and the wall can be sealed with firestop caulk.

As an alternate to the wrap strip “tuck-in” method described herein; a firestop collar can be positioned around the pipe and fastened to the wall. (See Figures 1-4) Firestop collars are metal shells that contain a firestop wrap strip. The metal collar has mounting tabs that seat against the wall surface. There are shorter retaining tabs opposite the mounting tabs that contain the material as it activates under fire conditions and begins to intumesce. When collars are used, the fasteners should always be steel. Do not use plastic or lead shields. In gypsum board walls, use steel hollow wall anchors in conjunction with steel fender washers. In concrete walls, use steel masonry screws in conjunction with steel fender washers. Examples of wrap strips include SpecSeal® Series SSW Wrap Strips. Examples of firestop collars include SpecSeal® Series LCC Firestop Collars. Both products are available from Specified Technologies, Inc., as well as other leading manufacturers of firestopping products.

Ensuring that the central vacuum system is installed properly is important, but the penetrations through walls intended to provide a measure of fire resistance can be equally important from a life and property safety perspective. Professional installers should be aware of local requirements and plan accordingly. Always ask your builder whether they are aware of local requirements or consult the local authority having jurisdiction. v

This article was written by J.P. Stahl, Jr. the director of technical services for Specified Technologies, Inc. (STI). Headquartered in Somerville, NJ, STI’s SpecSeal® Firestop Products.

Reprinted from Central Vac Professional, March 2007