Beam Capacity by and for Dummies

Few things chap the collective hiney of our staffers than the work of an English Lit major turned freelancer, so many of whom infested eHow.com in the fast and furious days before the Google's Panda update. Want fifteen bucks? Choose some random topic, reword a tangentially-related reference from the web (or just follow the MSU¹ playbook), hand it off to another English Lit major for "fact-checking," and move on to the next topic you know nothing about. Want an example? Check this one out: it's a  HomeSteady.com post by Rebecca Macken on "Single Point Weight Capacity of a Wood Beam."

No one here knows precisely what the OQ had in mind: perhaps someone wanted a general engineering reference for planning a structure, but we don't know and, sad to say, never will. What we do know is that a number of variables enter into the calculation including (but not limited to) length of span, live load, dead load, wood species, support scheme, and lumber dimensions. Whatever the case, it's for sure that Macken didn't cover the topic of weight capacity while getting her two English Lit degrees.
So what did Rebecca say about her topic? Well, according to Becky,

"Generally, you can find out the capacity by dividing the total load bearing weight by the length of the beam..."

...which, we have to point out, doesn't make a lick of sense. Macken goes on to provide an example of her alleged calculation:

"For example, a 9-foot-long beam span, requiring a total load bearing of 680 pounds, has a single point capacity of approximately 75.5 pounds."

We looked at Macken's reference, and truth be told, we have no idea where that crapola came from, We did note that the reference (a publication by the American Wood Council) included a table of about 1,000 possible configurations for the "9-foot-long beam span" in question, not one of which is 75.5.

It's readily apparent that our Dumbass of the Day didn't understand the question and didn't understand her reference either; hence the award. Any questions?

¹ MSU: make shit up

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