Improved wall systems for fire performance of houses

Volume 18, Number 3

Interior wall burning

Impact of one-hour residential fire on an interior wall assembly during recent experiments conducted at NRC

NRC is investing in a new phase of research to support industry clients on the fire performance of single-family houses constructed with innovative materials, products and systems. The work is part of an exhaustive long-term study to assist code authorities and builders to understand how these innovative technologies behave in a fire and affect the safety of occupants.

In this new phase, researchers will characterize and de-risk innovative load-bearing foundation walls and above-grade wall systems that support the floor systems. These include preserved wood foundations, insulating concrete forms, and structural insulated panels. The research projects will include a study on the impact of innovative combustible insulations, which may adversely affect the performance of a wall during a fire.

Historically, houses were constructed using solid wood and other conventional materials. Over the past twenty years, innovative composite materials and design approaches were developed, such as engineered wood systems for floors and novel structural systems for walls. Little was known about the behaviour of such innovations in the event of a fire, leading to concerns about occupant safety.

Testing innovative products in fire scenarios

NRC investigated the fire performance of innovative products for houses in 2003 for a consortium of clients and at the request of the Canadian Commission on Building and Fire Codes. Researchers conducted a comprehensive series of experiments in a full-scale facility simulating a single-family house with a basement fire. First studied were floor/ceiling assemblies that were left open and unprotected on the basement side (see Construction Innovation, Vol. 14, No. 1). In follow-up tests, the same assemblies were protected by various combinations of gypsum board, a suspended ceiling, and sprinklers (see Construction Innovation, Vol. 16, No. 2).

The upcoming tests on wall systems will employ the same research facility, with modifications to address the new scope of the project. The results, along with those from the previous work on floor systems, will be used to establish parameters for determining acceptable performance in a fire. A critical parameter, for example, is the ability of floor and wall systems to remain in place and structurally sound long enough for occupants to escape.

Our researchers will support collaborative projects by also working with our codes specialists and regulatory authorities in the provinces and territories to develop these fire performance criteria. These will become the basis for appropriate performance-based requirements in construction codes.

Once new regulatory provisions are in place, manufacturers will be further able to accelerate commercialization of innovative products and systems to meet the performance requirements. Our evaluation experts will assist these companies by establishing a technical basis for evaluating the fire performance of their innovations. From this will flow evaluation procedures that ensure timely assessment of these products, leading to their quick uptake in the marketplace.

Contact

Alex Bwalya
Telephone: 613-993-9739
Email: Alex.Bwalya@nrc-cnrc.gc.ca