Hot New Video! Full-Scale CLT Fire Testing Yields Impressive Results

Trust us, you’re going to want to see this.

Forest Products Laboratory researchers conducted fire testing on a two-story cross-laminated timber (CLT) structure. Watch the short video below to see these one-bedroom apartments go up in flames, and to find out how CLT performed in the heat of the moment.

You can read more specifics about the tests in this previous LabNotes blog post, or if you’re really into the details and data, check out the full FPL general technical report.

Southern Exposure: Long-Term Field Testing of Wood Protectants

When researchers are looking to evaluate the performance of wood protectants, the harsher the environment the better. Which is why Forest Products Laboratory (FPL) researchers put specimens to the test in the Harrison Experimental Forest (HEF) in Saucier, Mississippi, and have been doing so for 80 years.

Generations of FPL researchers have used the HEF field site for sub-tropical field testing. Here Oscar Blew is rating posts at the HEF (1950’s).

Located about 35 miles north of the Gulf of Mexico, this sub-tropical field site receives about 60 inches of rainfall a year and has a mean temperature of 68 degrees Fahrenheit. The wood decay hazard in this area is rated “severe” according to the American Wood Protection Association Use Class Rating System and there is significant subterranean termite activity. When in ground contact, untreated wood rarely lasts 12 months in the HEF, to which researchers respond “challenge accepted.” Continue reading

Turning Up the Heat: Fires Test Performance of Tall Wood Buildings

Wood buildings provide an array of economic and environmental benefits. Interest in capitalizing on those benefits by constructing mid- to high-rise buildings using cross-laminated timber (CLT) is growing. CLT is made from layers of dried lumber boards stacked in alternating direction at 90-degree angles, glued and pressed to form solid panels. These panels have exceptional strength and stability and can be used as walls, roofs, and floors. Additionally, calculations have shown that a seven-inch floor made of CLT has a fire resistance of two hours.

In order for wood structures to rise above six stories without special building official permission, changes to the International Building Code are needed. It’s a tall order, but researchers from the Forest Service’s Forest Products Laboratory (FPL) recently completed a series of fire tests that will address concerns about fire performance of wood buildings and help take them to new heights. Continue reading

Meet the Researchers: FPL Scientists Featured in Crossties Magazine

The Railway Tie Association publishes a magazine, Crossties, for producers and users of treated wood crossties and related products. The May/June 2017 issue introduces a new regular feature called “Meet the Researchers,” and it kicks off by showcasing researchers from the Forest Products Laboratory (FPL).

This makes perfect sense, as one of the original goals for early FPL scientists was developing preservatives for railroad ties. More durable rail ties lengthened the service life of ties in use, and helped ease the demand for lumber, as trees were being cut at alarming rates across many northern and western forests.

Over time, lumber treatment and preservation research focused on environmental concerns as well as durability. Today, FPL researchers in the Durability and Wood Protection group continue to work on improving the treatment of wood.

You can read the full issue of Crossties here. See page 13 for the Meet the Researchers feature.

Time in a Bottle: Finding New Life for an Old (Yet Reliable) Test Method

The simple soil bottle presents an extremely useful tool for predicting performance of preservative treated, modified or naturally durable woods. The methodology was developed in the 1940s exclusively for evaluating wood preservatives against wood decay fungi. It has been adapted over several decades to include naturally durable woods, wood plastic composites, and engineered wood products, and we use it constantly here at the Forest Products Laboratory (FPL).

The basic premise of the soil bottle is a material is presented to an actively growing fungus in an otherwise sterile environment. The resistance of the material to fungal degradation is determined by comparison to reference materials (non-durable species or treated reference material). The soil bottle also presents an excellent tool for studying basic fungal biology whereby cellular changes in wood during the decomposition process can be analyzed.  The soil presents a refuge for the decay fungus as well as a source for moisture and transported ions relevant to the decay process.

Past, present and future research at FPL is looking at ways of modifying the standard soil bottle setup to be even more useful for the evaluation of wood and wood protectants. Here are just a few examples of where FPL researchers are pushing the boundaries of the standard soil bottle: Continue reading