AGENDA #4h

memorandum

to:	Roger L. Stancil, Town Manager
from:	Daniel L. Jones, Fire Chief Lance Norris, Inspections Director
subject:	Response to Petition regarding Combustible Landscaping
date:	October 22, 2007

PURPOSE

The purpose of this report is to present information from the staff regarding combustible landscaping in certain occupancies. This report is generated following a petition to the Council from Mr. Ray Harris, dated September 9, 2007 with concerns surrounding recent fires in pine straw used as decorative landscaping.

BACKGROUND

Currently, there are no provisions within the NC State Building Codes or Fire Prevention Code which regulate the installation or use of combustible landscaping around the perimeter of commercial buildings. Similarly, there are no restrictions within the Chapel Hill Code of Ordinances addressing this. So far this year, the Chapel Hill Fire Department has responded to several fires which originated in combustible landscaping, specifically pine straw, which then quickly spread to the structure itself. The common ignition factor for each fire was determined to be carelessly discarded smoking material, which easily ignited the pine straw landscaping. These three similar fires, each at residential apartment complexes (101 Misty Woods Circle, 500 Umstead Road, Bldg B, and Tyler Creek, Bldg. H) caused a combined estimated fire loss of $72,000. With the severe drought conditions that our area has faced this season, this has been a recent concern of the Fire Department.

DISCUSSION

The Town of Chapel Hill is not the only jurisdiction facing this issue. Currently, the City of Raleigh, NC is considering local restrictions following a fire at the Pine Knoll Townhomes on February 22, 2007. That fire, which was started by carelessly discarded smoking material igniting decorative pine straw landscaping, destroyed 32 townhomes. Due to the extremely combustible characteristics of pine straw, the small fire quickly grew and extended to combustible vinyl siding on the buildings exteriors and traveled vertically through the vinyl soffit, involving the buildings’ attics. Following this catastrophic fire, the Raleigh City Council contracted with Schirmer Engineering of Charlotte, NC to provide a fire protection study of the incident, which includes recommendations to reduce similar instances. Similarities of this fire to recent fires in Chapel Hill proves the information provided in the technical report valuable and worthy of consideration locally. This report can be reviewed at http://www.raleighnc.gov/portal/server.pt/gateway/PTARGS_0_2_103654_0_0_18/Townhouse_ Fire_Report_Pages_1-50.pdf. The two controllable factors identified by Schirmer in their report were 1) combustible construction, namely the combustible soffits, which allowed vertically growing fire to penetrate and enter the buildings attic area; and 2) combustible landscaping.

In response to this fire and report, the NC Building Code Council enacted a Temporary Rule on March 27, 2007, and an Emergency Rule on April 5, 2007 to address the combustible soffit issue. This revision to section 302.1, exception 2 of the NC Residential Code now requires non-combustible soffit material be used in townhouse construction. This rule change is not retroactive and will only effect new construction after the revision date. All existing residential construction, including apartments and townhomes will not be required to update to fire resistive soffit material, therefore not eliminating the fire risk in older construction.

With regard to the other controllable factor, combustible landscaping, testing at prominent research facilities have concluded that pine straw (i.e. pine needles) should not be used close to structures as it is considered one of the most highly flammable landscape materials.

From testing data documented in a joint effort by the National Institute of Standards and Technology (NIST), the Building and Fire Research Laboratory (BFRL), the University of Florida, and the United States Forest Service Research Station, the flammability characteristics of pine straw have been tested and documented to show that pine straw has inherent properties that yield high ignitibility, flame spread and heat release rate. Its low surface area to mass ratio makes it easy to ignite and quick to be consumed. Its resin content produces high heat release rates when compared to other landscape mulches.

Four common mulch types used as decorative landscape material (pine straw, large pine bark, small pine bark and cypress mulch) were tested. Results demonstrated pine straw to be the most hazardous, yielding the fastest rate of spread, the highest flame rate, the highest temperature and the most complete fuel consumption when compared to the other three mulches (Table 1). According to the test report, pine straw has the greatest potential of the four mulches to rapidly create an ignition source for adjacent plants and structures.

Table 1. Mulch Type Comparison

The results of this testing was recently presented at the 2007 Annual Fire Conference at NIST in Gaithersburg, Maryland. The researchers who conducted this testing and presented this information concluded that pine straw should not be used close to structures. Although most products used for mulching/bedding purposes in landscaping are combustible, the ease of ignition, fast rate of spread and high flame rate make pine straw inherently dangerous.

It is also important to mention that in local instances, fire ignition has taken place in the pine straw, which has transferred fire to adjacent combustible, decorative vegetation. The document Firewise Landscaping in North Carolina is available at www.ncfirewise.org and lists plant species found in NC with flammability ratings of Low, Medium, High and Extreme.

Conclusion

Following a review of the technical and practical information located on this topic at request of the Town Council, Town staff agrees that improperly discarded smoking material into pine straw landscaping materials has been the cause of recent fires in local residential (apartment/townhouse) complexes. Likewise, once ignited, the fires have quickly grown and spread to adjacent decorative vegetation and combustible construction members. Similar fires, in other North Carolina jurisdictions, have proven to be catastrophic. In response, other municipalities have enacted, or are proposing restrictions on the use of pine straw as landscaping media.

Collaboratively, the Town of Chapel Hill Fire and Inspections Departments have developed an ordinance proposal that addresses the hazards of pine straw and other highly combustible landscaping products for the Council to consider. We feel that this ordinance will result in the decrease in frequency and severity of fires initiated by carelessly discarded smoking materials into landscape materials within the Town of Chapel Hill.