Tag Archives: nail laminated post

Dear Mike Burkholder

Dear Readers: For those of you missing the past two days, or yesterday’s blog at most, please back up a day or two to bring you up to speed for my response to a seemingly heated rejoinder by Mike Burkholder of Ohio Timberland Products to a blog I wrote.  This is published in it’s entirety.

Dear Mr. Burkholder ~

Thank you very much for your comment response to my blog article on nail laminated columns. I’m humbled someone with your extensive bacPole Barn Guru Blogkground and experience would take the time from their busy schedule to write.

On an all-too-frequent basis we are asked by clients to compare the Hansen Pole Building against those who profess to be offering the same or better. Sadly, there are resellers of the Nail-Lam “PLUS” columns, manufactured by your company – Ohio Timberland Products, Inc., who are promoting the columns as being glu-laminated columns. Your website (www.ohiotimberland.com) clearly delineates your products as being nail-laminated, leaving the question to be are the resellers confused about the columns you manufacture, or is it a deliberate misrepresentation on their part?

From the information provided on your website, if a client told me they had to have a nail-laminated column, there is more than a fair chance I would recommend your product over any others for two reasons.

Number One – the structural finger joint between the upper and lower portions of the column. I’ve been told, by more than one glu-lam manufacturer, of the finger joint being the toughest part of the process to get right, and it appears you have “glued it” (as opposed to “nailed it”). The structural finger joint has to be a huge strength step up from non-reinforced butt end splices, flat steel plates or even “gang nail” style plating.

Number Two – your use of a through mechanical fastener, as opposed to just nailing, to join the individual plies. I began fabricating nail laminated columns at my first business about 30 years ago. When we had them tested at the Oregon State University Forest Products lab, we found nearly every failure came from the middle ply – because it had twice the number of nails into it (as the nailing was from both sides, into the middle member). Your superior fastening method creates a far more even load distribution across the members.

In my humble opinion, these two features alone should be able to be presented as benefits to the end user which should sway anyone who is considering a nail-lam to yours, regardless of the price point.

Possibly without realizing it you have your foot in the door at Hansen Pole Buildings, for a tremendous selling opportunity. We’ve always endeavored to offer to our clients the best possible value for their post frame building investment. All you need to do is provide a preponderance of evidence supporting the benefits to the ultimate end user of your product – the building owner. I’d encourage you (or one of your sales team) to contact Eric Graff, the managing partner of Hansen Pole Buildings, to make a presentation.

I personally will extend to you this offer – you are invited to guest blog about your Nail-Lam “PLUS” columns and I will run your offering verbatim, with small caveats. It should be written to the end user (again, the building owner) and extoll the benefits to them (not merely features). Any claims of superiority should be backed up by factual proof (e.g. testing results). And – once your article is published, a link to it is added on your website.

For my own curiosity I do have a couple of questions, which I am relatively certain you can easily answer.

If I am not mistaken, you testified before ALSC (American Lumber Standards Committee)in 2012 regarding design values for visually graded SYP. This effort resulted in your landing on the SPIB (Southern Pine Inspection Bureau) T&R Committee. This might lead me to believe you are pretty much an expert when it comes to the use of Southern Pine. 

In looking at the design value table presented on https://ohiotimberland.com/literature_zoom.html I see an “E” value presented of 1,700,000. When I look at https://www.southernpine.com/app/uploads/200N_NDV_tables1-2_2013_L.pdf effective June 1, 2013 the “E” value for No. 1 Southern Pine is 1,600,000. I can only surmise this is a resultant of actual product testing, or my unfamiliarity with the intricacies of the NDS. The same would apply to deriving an Fb value of 1897 psi (for a multiple 2×6 product) from a base value of 1350 psi.

I’m always striving to learn more and would appreciate it if you could take the time to educate me on this.

The other would be (from your website), “adhesive between plys greatly cuts down on interlayer slip resulting in better weak-axis stiffness”. If you could share with me the testing results on this, I’d be very interested in reviewing them. I can see how this could be a benefit (provided the stiffness is adequate) in being able to utilize the columns in an unbraced situation such as open side sheds, etc.

Again, thank you very much for your time and I will look forward to hearing from you in the near future.

Best regards ~

Mike, The Pole Barn Guru

Pole Barn Detective: Is it a Glulam?

Is it a Glulam?

Usually the process works this way – check with the Planning Department to confirm the desired building can be constructed on the property, have pole building plans prepared by a registered design professional (RDP – engineer or architect), apply for and be granted a Building Permit, then build.

The photo of the inside of this particular building, is a case where the building owner skipped steps 1, 2 and 3 going directly to #4. The building owners problems came – when they needed to get a permit for electrical and oops!!

Just in case anyone was wondering, this is NOT a Hansen Pole Building kit package.

Anyhow – the Building Official is now questioning the posts used in this building (see photo).

Is It A Glulam?In case anyone is even wondering, the column shown is NOT a glulam. What we are looking at, is six pieces of 2×6, which have been glued together with construction adhesive. Quality control, as far as aligning the 2×6 members, was not necessarily high on the list of important things when they were assembled. The alignment issue is actually just one of aesthetics, not of functionality.

Now we are going to discuss structural functionality.

The glue can be discounted entirely, as construction adhesives are not designed for this type of structural application. What we have here is nothing more than a nail-laminated column,which does not qualify to call it a glulam.

In 1984, my academic post frame hero (Dr. Frank Woeste), was a co-author of a paper on “Nail Laminated Wall Columns from Dimensional Lumber” (see TRANSACTIONS of the ASAE Volume 27, Number 4, pp. 1127-1130, 1984). This paper reported the test results from nail-laminated columns, with internal non-reinforced butt end splices.

In their testing, the lower members were staggered two feet from each other, similar to the photo which probably used 8 and 10 foot long 2×6 on the exterior and a 6 foot in the center. Dr. Woeste used #2 Dense Southern Pine for testing (which is greater in strength than the #2 material found in the local lumber yard).

The plies were nailed together with 12d nails, in a specific pattern. They were placed with two nails every foot outside of the spliced area, and four inches on center in the four feet of splice zone (the area between the shortest and longest members). Each pair of nails was staggered from the previous pair, in a specific pattern.

Provided the columns in the photo are nailed adequately to match the testing (anyone interested in taking this bet?), the results of the test, adjusted downward from the difference in strength from the use of #2 grade lumber rather than #2 Dense, would probably be a fair approximation of strength.

The results from the column testing, compared the strength of the nail-laminated columns, to the values of 6×6 #2 Southern Pine solid sawn columns. The results of the tests showed the nailed up columns were only 64% as strong in bending, as a solid sawn column! The test results were compared against testing of other columns which used reinforced splices (either with 5” x 24” 20 gauge flat steel plate, or with pressed in “truss plates”). These comparisons demonstrate the discontinuous (non-reinforced) joint between the vertical members is the weakest link of the nail laminated wall columns.

While I do not know the dimensions or climactic loading of the building in question, I have seen another photo of this building which leads me to believe the building is 14 to 16 feet in height.

My opinion? Based upon what I can see, this building is going to require some serious structural engineered repairs to the columns, in order to be adequate to carry the loads.  And it won’t be cheap, the engineer fees nor the repairs.