#487 – How to Size and Install a Sprinkler Escutcheon Extension Tube

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Fire sprinkler escutcheon extension tube

Extension tubes can cover long fire sprinkler drops or dry barrels for a seamless look

The positions of fire sprinklers relative to branch lines and finished surfaces can vary; however, a standalone escutcheon is usually available that fits most installation scenarios. When a sprinkler projects significantly from a surface, 401 adjustable escutcheons—aka “skirt and cup” escutcheons—typically provide the extra length needed to complete the job, hiding many long sprinkler drops. However, if a 401 escutcheon still isn’t long enough, a sprinkler escutcheon extension tube is needed to fill the gap.

Learn more about how to pick and use these accessories, including:

Feel free to check out QRFS’s selection of adjustable 401 escutcheons and escutcheon extension tubes, as well as our complete inventory of other escutcheon styles and accessories.

NFPA’s escutcheon rules

The National Fire Protection Association’s NFPA 13: Standard for the Installation of Sprinkler Systems specifies rules for installing escutcheons:

  1. All sprinkler escutcheons must be metal or listed, the latter of which means it’s been tested and certified to fit and work with a specific sprinkler as part of a “listed sprinkler assembly” (7.2.6.1). Some escutcheon types are both metal and listed, while others are just metal.
  2. Only recessed escutcheons or those used with “flush-type sprinklers” must be listed— more specifically, be a “part of a listed sprinkler assembly.” (7.2.6.2)

Regarding the second rule: Recessed and flush-type sprinklers both have a portion or all of the sprinkler’s body positioned within a ceiling or wall. Therefore, NFPA requires their escutcheons to be listed to ensure that the sprinkler remains in place and neither the escutcheon nor the finished surface obstructs its operation or spray pattern. In contrast, sprinklers that are installed with 401 adjustable escutcheons (and extension tubes, if needed) project completely out of a finished wall or ceiling, so there is basically no chance of the surface blocking the spray. Thus, neither 401 escutcheons nor any accompanying extension tubes need to be listed.

Regarding the first rule: Escutcheons must be made of metal or listed to ensure that they can withstand heat and won’t melt. In some cases, these accessories also specifically seal penetrations in fire-rated barriers, where the heat-resistance conferred by metal becomes even more crucial. So, while neither 401 adjustable escutcheons nor extension tubes must be listed, they should still be metal!

The bottom line: As long as sprinkler escutcheon extension tubes are made of metal, like the ones QRFS carries, and are installed correctly, they are compliant with specific NFPA mandates and their intent. You can read more about which types of escutcheons must be listed and why in our previous blog, but the rules for different sprinklers and installations are summarized in this image:

Listed escutcheon rules
Sprinkler installations where the entire sprinkler frame (starting at the base) projects from a surface do NOT require listed escutcheons,as shown in the bottom two installations. Since extension tubes are used with 401 adjustable escutcheons (bottom left image), neither the escutcheon nor the tube requires a listing, as the installation style should have no chance of disrupting the sprinkler’s spray pattern or operation.

How to size an extension tube

The only dimension to worry about when choosing an extension tube is its length, not its width/diameter. That’s because adjustable 401 escutcheons all have skirts and cups with openings of about the same diameter, and the extension tube is a split cylinder that fits into these openings under tension. Thus, you must simply choose the appropriate length of a tube based on the distance between the skirt and cup and what these parts fail to cover.

Escutcheon extension tubes come in 4″, 6″, 8″, and 10″ lengths. Choose the length that is closest to but a bit longer than the distance of the exposed fitting or barrel between the skirt and cup of a 401 escutcheon. These measurements don’t need to be precise, because the extension tube will slide into the skirt and cup at variable depths and hold in place due to tension, and the longest 401 escutcheons with “A skirts” have about 3” of adjustability. Thus, installers have some leeway in the length measurement.

Size sprinkler escutcheon extension tube
Choose the tube length that best covers the exposed gap between a 401 escutcheon’s skirt and cup, keeping in mind that you’ll have some room for adjustment by sliding the extension tube into the skirt and cup. The image on the right shows 6″ and 4″ extension tubes—you’d choose the 6” model for this installation.

How to install a sprinkler escutcheon extension tube

The steps are simple for a new sprinkler installation:

  1. Slide the 401 escutcheon’s skirt around the exposed sprinkler drop (or barrel, etc.).
  2. Squeeze the split sides of the extension tube together so they fit around the drop and inside the escutcheon’s skirt and cup.
  3. Slide the extension tube into the escutcheon’s skirt and position the sprinkler and cup so that the sprinkler will be ready to be installed into the fitting.
  4. Adjust the extension tube as necessary by sliding it into the skirt and cup; then tighten the sprinkler and the 401 escutcheon’s cup into place with a compatible sprinkler wrench.

That’s it. The parts are held in place by both the tension of the installed sprinkler and the tension of the extension tube’s split cylinder.

Install sprinkler escutcheon extension tube
Installing the extension tube is as simple as pushing the sides of the split cylinder close enough together so that the tube fits inside both the escutcheon’s skirt and cup on either end.

The steps to install an extension tube with a retrofit 401 escutcheon are similar to the procedure above, except these retrofit accessories can be installed after a sprinkler is already tightened into its fitting.

Retrofit 401 escutcheons feature a split cup that snaps into place around the base of a sprinkler and a coiled extension tube, eliminating the need to drain the system and remove a sprinkler just to install an escutcheon. Installers can remove an old, faulty escutcheon by carefully cutting the inner cup off with tin snips, followed by snapping the new split cup into place.

retrofit 401
“Retrofit” 401 escutcheons have a split cup (right) that allows placing the cup around a sprinkler that is already installed—no need to drain the system and remove the sprinkler. An extension tube still fits between and into the skirt and cup, as with a non-retrofit escutcheon.

Cover long gaps and create a clean look with the right accessories

Whether a sprinkler connects to an extra-long drop to avoid obstructions, or you need to cover the lengthy barrel of a dry sprinkler that projects out of a finished surface, sprinkler escutcheon extension tubes have your scenario covered (literally).

Shop our selection of extension tubes in 4″, 6″, 8″, or 10″ sizes, available in chrome or white finishes, plus 401 adjustable escutcheons, including split-cup retrofit models.

If you have any questions or need assistance with placing an order, please don’t hesitate to contact us.

This blog was originally posted at blog.qrfs.com. If this article helped you, check us out on X @QuickResponseFS.

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