Tag Archives: pole barn fires

Pole Building Burn Time

There are times when I wonder if some of our clients lay awake at night trying to think up new questions to ask our Hansen Pole Buildings’ Designers, which have never been asked before. In today’s question – Building Designer Brenda was asked what the “burn time” is on one of our buildings.

Of course I asked Brenda specifically what her client was looking for (seems there is always a Paul Harvey), however we have not gotten a reply, as of this writing.

I’ve written in the past about the fire resistance of wood: https://www.hansenpolebuildings.com/blog/2012/04/fire-resistance-of-wood/

Pole Building FirePole (post frame) buildings, without special provisions being made, are not inherently any more fire resistive (or fire yielding) than the average stick frame structure. Think about it – they are both wood frameworks, so pole building burn time is comparative.

Methods are available to establish fire resistance, both as tested and prescriptive assemblies. https://www.hansenpolebuildings.com/blog/2013/11/establishing-fire-resistance/

The American Wood Council publishes the NDS® (National Design Specification® for Wood Construction). Their Technical Report No. 10 contains formulas for Calculating the Fire Resistance of Exposed Wood Members. For those of you who are aspiring engineers or just enjoy playing with numbers and complicated formulas (and have an excess of time of your hands) it can be perused here: https://www.awc.org/pdf/tr10.pdf.

Much has been made, in the building community, as a resultant of the January 21, 2015 fire at a 240 unit Edgewater apartment complex fire. You can see the video here: https://search.yahoo.com/search;_ylt=A0LEVzNx12FVEoQAsBVXNyoA;_ylc=X1MDMjc2NjY3OQRfcgMyBGZyA2NybWFzBGdwcmlkA0JTbXJyUkZDU0VhNzFiUkhhQnYyb0EEbl9yc2x0AzAEbl9zdWdnAzQEb3JpZ2luA3NlYXJjaC55YWhvby5jb20EcG9zAzAEcHFzdHIDBHBxc3RybAMEcXN0cmwDMzEEcXVlcnkDRWRnZXdhdGVyIGFwYXJ0bWVudCBmaXJlIHZpZGVvcwR0X3N0bXADMTQzMjQ3NTc2Ng–?p=Edgewater+apartment+fire+videos&fr2=sb-top-search&fr=crmas

The fire prompted talk of legislation to toughen building codes. Fire officials who responded to the fire said it was worsened by lightweight materials, such as engineered wood, and an open, truss style roof.

“All wood burns, it doesn’t matter if its solid wood or little chunks glued together,” said Daniel Madrzykowski, a fire protection engineer with the National Institute of Standards and Technology, a part of the U.S. Department of Commerce. The difference, he said, is a solid piece will take more energy from a fire to ignite and will burn longer before it loses its strength.

Back to pole building burn time…..the dictate of failure due to fire will be a resultant of the weakest link in the chain. Without the use of fire retardant treated lumber, sprinkler systems, or fire walls – it comes down to how quickly will a nominal two inch thick piece of lumber burn through?

In a typical pole building, roof purlins and floor joists (in multiple floored buildings) are likely to be the weak links which would result in a potential collapse. In the AWC NDS Technical Report No. 10, Appendix B, Table B1, is given the “Design Load Ratio Limits for Solid Wood Joists”. Whether 2×6 or 2×12, a member supporting no load (think of a roof with no snow), has a 20.4 minute structural fire resistance time. When loaded to 100% of capacity, the same members are good for 10.6 to 11.3 minutes.

Why might these numbers be the same? Because the members least dimension is the 1-1/2” thickness! This, in my humble opinion, is one more reason the Hansen Pole Buildings actual double truss system is advantageous. The trusses are physically connected together, creating a three inch thick member – hence potentially doubling the time for a structural failure due to fire.

Pole Barn Fires

Break out the Marshmellows…

I get Google Alerts for any articles with pole barn or pole building in them. Pretty much every day there are one or more stories about barns burning down (think of how many houses burn down every day in the USA and a barn a day is insignificant). As sad as a burned down barn may be, there is some humor to be found in some of these stories.

From a story by Everton Bailey, Jr. at www.oregonlive.com:

“The blaze was contained to the 40-by-100 foot barn, no people were injured but a search is ongoing for possible chickens that may have been in the area.”

Were the chickens arson suspects? Trying to escape to be free range?

Nothing like barbequed chicken!

From www.journalgazette.com:

“While firefighters fought the blaze, officials realized the pole barn, near the intersection of Butler and Hillegas roads, was actually outside the city limits.”

What were the city firefighters going to do, leave the pole barn to burn down because it was “on the other side” of a line?

From an article by Jeri Thomas at www.drgnews.com:

“The Pierre Rural Fire Department responded early this morning to the report that a large structure was on fire on property east of Pierre.  Department members were summoned to put out the fire in the large pole barn about 3:45 a.m. this morning-two miles south of Highway 14 near 206th Street.” 

BBQ Sauce“Also helping at the scene was the Oahe Chapter of the American Red Cross.  No other structures are located on the old farmstead near the pole barn, but Kruger says the 65 X 120 building contained farm equipment, balers, and feed.  Also, there were pigs in the building and Kruger says some of the animals succumbed to the fire.”

The American Red Cross supplied Sweet Baby Ray’s Barbeque sauce for the ribs afterwards.

And the winner of the “Darwin Award” is in this www.thetelgraph.com article by Greg Olson:

“A rural Winchester man was injured Wednesday evening in a fire that destroyed a 40-foot by 50-foot pole barn about 8 miles east of Winchester.

Rueter said Winchester firefighters were called to the Ben Brickey farm on Ratcliff Road about 5:30 p.m., and when they arrived they found the barn engulfed in flames. “We were told that Ben Brickey was attempting to light a wood stove in the shop portion of the pole barn when diesel fuel he was using to start the fire ignited and spread to his legs and a pile of firewood,” Rueter said. “At that time, his son Dillon took his dad out of the building and put out the fire on his father’s pants.”

I am sad to hear when anyone is injured, but sometimes I just have to shake my head and wonder “what WAS he thinking?”  What more could possibly be said after this?

Be careful folks – and keep fire extinguishers handy!