Chimney chase & top shroud fire case report: this article provides photos and description of a Moorpark CA chimney fire whose origin was an unsafe chimney top shroud. Remarkably the shroud bore a counterfeit UL listing label.

A history of building fires traced to improper construction and installation of non-listed decorative chimney top shrouds has led to expert recommendations to improve building safety and reduce fire risks discussed further at CHIMNEY SHROUDS.

Chimney Fire Case Report: Unsafe Top Shroud & Counterfeit UL Label

Watch out: according to both Steve Werner and to Dale Feb, some fireplace top shrouds or surrounds installed on some chimney chase tops may unsafe due to heat trapping at the chimney top. Such shrouds usually violate local and national building codes as well. The house fire illustrated by these photographs (provided by Mr. Werner) occurred in Moorpark CA, and was attributed to an un-listed and unsafe chimney top decorative shroud atop a wood framed fireplace chase.

Common causes of factory-built fireplace and chimney and chimney chase fires are the combination of a metal or factory-built fireplace or fire-box and chimney combined with a decorative chimney top cap or shroud that was installed over the manufacturer's spark arrestor and cap assembly. At below left you can see the remains of the un-listed chimney top, now on the ground after the building fire.

At CHIMNEY SHROUDS we noted reports of chimney & house fires traced to unsafe decorative shrouds installed atop wood chimney chases and factory-built metal chimneys. Baird (1991) reported on a number of chimney & house fires occurring in California from 1989 through the early 1990's and explained that all of the fires investigated occurred in

chimney chases that had been equipped with decorative sheet metal "shrouds".

At below left you will note the very extensive roof and ceiling fire damage to the home where this fireplace shroud was installed. At below right the worker is using red paint to mark an unsafe chimney top termination.

Baird also reported on the reasons that un-listed chimney top shrouds were the cause of serious building fires and recommended a variety of steps to reduce the risk of future fires including using only listed chimney top shrouds and the inspection of both existing and new factory-built fireplace and chimney installations.

Baird concluded that "Failure to fabricate a chase flashing according to the manufacturer's instructions constitutes a violation of the Uniform Mechanical Code" and concluded that "... future installations must not include unlisted attachments to a listed [fireplace or chimney] assembly."

Building Code Citations for Decorative Chimney Top Shrouds

Fake or "counterfeit" UL listing label compared with a valid UL label for chimney top decorative shrouds

Above: counterfeit UL listing label found on the unsafe chimney chase top shroud attributed to cause of the fire described here. At the request of UL we have overlaid all of these listing labels with a red imprint to make clear that copying of these or any other illustrations at InspectApedia is a violation of federal copyright law as well as other rights and statutes enforced by the listing agency, in this case Underwriters Laboratories.

Below is an example of a valid chimney top shroud UL Listing Label from Chimney King

More examples of listed chimney top shrouds and proper valid UL listing labels for these products can be seen at CHIMNEY SHROUDS.

• International Mechanical Code IMC (2000), M74-98 806.6, ratified 9.98, model building code for the United States,
  806.6 Decorative Shrouds. Decorative [chimney top] shrouds shall not be installed at the termination of factory-built chimneys, except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with section 304.1. Reason: Decorative shrouds have been the cause of roof and chase fires
• International Residential Code (IRC) (2000), R1002.2 ratified 9/99, 1000.2 Decorative [chimney top] Shrouds. Decorative shrouds shall not be installed at the termination of factory-built chimneys, except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with the manufacturers installation instructions.
  
  Reason: Decorative shrouds often allow for the creation of temperatures in excess of those permitted in UL 103 and UL 127. Decorative shrouds have been the cause of chase top fires ...
• International Fire Code (IFC) (2000), IFC 603.6.3, 603.6.3 Decorative Shrouds. Decorative [chimney top] shrouds installed at the termination of factory-built chimneys shall be removed, except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with the manufacturers installation instructions.
  
  Reason: Decorative shrouds have been the cause of dozens of chase fires. As a non-listed part to a listed assembly, their use should not have been allowed in the first place.
• For Gas Direct Vent appliances, the UL and ANSI standards require any accessory (like a [chimney top] shroud) that is to be used with a direct vent appliance to be tested and listed with the unit.

- Chimney fire & UL label photographs were provided by Stephen Werner General Manager Chimney King, LLC P.O. Box 8 Gurnee, IL 60031 Corporate (847) 244-8860 Fax (847) 244-8694 Email: steve@chimneyking.com

Reference: https://inspectapedia.com/chimneys/Chimney_Shroud_Fire.php