Tag Archives: glulams

Sturdi-Wall Plus Concrete Brackets

Sturdi-Wall Plus Concrete Brackets

Long time readers will recall a previous article regarding Sturdi-Wall Plus concrete brackets:

https://www.hansenpolebuildings.com/2012/09/concrete-brackets-2/

Sturdi-Wall Plus brackets are a heavy-duty engineered anchoring system for attaching wood columns to concrete foundations and are generally used in post-frame buildings but have other applications as well. These brackets are made with ¼ “steel plate A706 rebar in either # 4 or # 5 size, depending on model.  Each bracket is precisely welded to meet engineering specifications and given a professional look with a baked polyester powder coat finish. Some brackets are available in a Hot Dipped Galvanized model for use in more corrosive environments.

Sturdi-Wall Plus brackets are used in a wet set concrete application and provide highest strength bracket to foundation connection when concrete is fully cured. SWP brackets require less concrete coverage than Sturdi-Wall brackets, allowing them to work well in pier foundations, post repair, and renovations. #4 rebar is used in all Sturdi-Wall Plus brackets, except SWP 8 Series where #5 rebar is used. Sturdi-Wall Plus brackets are available in Standard, OT and GL models.

Standard Models – Accommodate dimensional lumber and laminated columns, typically nailed together with no additional machining.

OT Models – Accommodate some planed laminated wood columns usually mechanically fastened and glued together.

GL Models – Accommodate most planed and glue laminated wood columns (glulams).

In March I attended NFBA’s (National Frame Building Association) 2019 Expo where I met with PermaColumn’s team and recorded this live video for you:

Ready for your new post-frame building, but don’t want to place columns into ground? Sturdi-Column Plus brackets may be just your solution. Call and discuss with your Hansen Pole Buildings’ Designer today at 1 (866) 200-9657.

Tops of Glulam Posts

This question was posed to Justine, who gets everyone’s wonderful materials to their pole building sites for Hansen Buildings:

top of glulam column“Justine, pardon me for being confused but: If the tops of glulam posts were manufactured that way to allow cutting, why are they not all that way?  There is no rhyme or reason to them. Some of them are laminated all the way to the end and some of them are not.  Some of them have one board not laminated in the 3 ply and some have no lamination between the any of the boards on the end.  

 If the lack of lamination occurs below the level of the truss, how is it supposed to carry the weight of the roof?  Since I have not yet received the trusses, or any of the hardware for that matter, I have no way of knowing the depth of the end of the truss.  I am concerned that the glulam posts with almost 2 feet of board that is not laminated will not reach my trusses at an acceptable level.

 The other question would be, if the glulam posts are not solid and the trusses are wider/narrower than the individual pieces how do I make a cut? Do I have to account for the gap in the board?   Also, when they are not laminated they are no longer straight, as you can see as they flare out at the end.” 

I happen to have spent some time in a past life working for a company which produces glu-laminated columns. In many cases the glue between plies is omitted from the upper portion of the laminations, for aid in the ease of cutting truss notches. While the goal is for this to be universal, it does not always occur.

This no glue area does not negatively affect the strength of the columns – the three plies do not somehow get magically stronger because of the glue!

So, what is the solution?

Once the height of the bottom of the truss notch above grade has been determined, any area between the glulam plies below this point can be nailed together to remove “gaps”.

The truss seat notches can then be cut into the tops of the glulam posts adequately to provide for full bearing of the trusses, and the column to truss connection can be completed per the provided plans.

Glulams vs. Solid Sawn Columns

A Hansen Pole Buildings client recently called his Building Designer Rick. The client was concerned as three ply glulams were provided for his pole building kit package, instead of the 4×6 and 6×6 solid sawn columns which were on his plans.  He is concerned his inspector will give him trouble about this and would like an e-mail stating all is good.

Always happy to oblige Rick and help out a client, this is what I wrote:

“At no extra cost to you, your building columns have been upgraded from solid sawn columns, to glulam columns.

The strength of any member which resists bending, is primarily determined by its fiberstress in bending (known as Fb) multiplied by the section modulus (Sm) of the member.

For information on the solid sawn columns, this makes for good reading: https://www.hansenpolebuildings.com/blog/2014/08/lumber-bending/

The design specifications for the Titan Timbers provided are here: https://www.timber-technologies.com/webfiles/fnitools/documents/column_specs.pdf

With a Fb rating of 1900 psi and a Sm of 19.9, the product of the two is 37,854 in-lb. Compare this to the values of solid sawn timbers and you (or anyone who might question them) can see the huge difference in strength provided by the glulams.”

In a not too distant past life, Dale (one of the owners of Timber Technologies, which manufactures the glu-laminated Titan Timbers) and I worked together for another glu-laminated column fabricator.

Both of us learned plenty from the experience.

In my case, I learned the values of glu-laminated columns other than just the strength (in many cases a three-ply 2×6 glulam will even replace a 6×8 timber!).

They are light weight. I’ve stood 24 foot long 6×6 columns in holes before. Weighing in at well over 200 pounds – it is a task! A triple 2×6 glulam – about ½ the weight!!

Properly fabricated, a glulam columns is going to also be perfectly straight, as well as prone to resist the bane of anyone constructing a pole building – warp and twist!

All-in-all this particular Hansen Pole Building customer got what is known as, “A pretty sweet deal”.

Pole Building Trusses

Pole Building Roof System – Dressed Up!!

For years I sat in church on Sunday mornings with my children and admired the magnificent trusses which supported the roof. Built from glulams with the joints connected with bolted steel brackets – they were nothing short of fabulous. To me (coming from a background of construction and prefabricated roof truss manufacturing), I believe I had a special attraction to them more than just the average parishioner.

Truss-FramingAs pole buildings have gravitated from the farms of the 1950’s into the mainstream of popular construction, their owners have been looking for more appeal than what was offered by the average tractor shed.

The aesthetics of massive exposed trusses somehow is appealing to many of us. By using glulaminated timbers to fabricate them, the members have very few flaws and can be readily finished to highlight the natural beauty of the wood.

By using prefabricated metal plate connected wood scissors trusses, the structure of the roof surface can be readily supported. These trusses may have conventional “heels” (the point where the top and bottom chords meet) and an exterior slope which is greater than the interior slope. By use of a raised heel, the bottom chord slope can be increased to give a more dramatic look, as well as creating a deeper insulation cavity.

Ceiling finishes are then often tongue and groove two or three inch thick material. Depending upon the spacing of the trusses, often no other bottom chord framing is required for their support.

Non-load carrying glulam trusses can be placed directly below the decking to give the impressive look, without sacrificing any of the “pretty” parts of the truss – as this work is being done by the hidden trusses above the decking.

Whether office space, a church, great room or man cave – if you want to “knock the socks” off your guests or clients, this one offers some distinct possibilities

Poles for Pole Barns

Some days it seems there are nearly as many possible design solutions for pole barn “poles” as there are pole barns!

Here is a brief overview of the organic (think coming from trees) ones. For the sake of brevity, I will limit this article to only applications where the columns are embedded in the ground.

Old utility poles – not a good choice for many reasons:

https://www.hansenpolebuildings.com/blog/2012/11/utility-poles/

https://www.hansenpolebuildings.com/blog/2012/11/used-utility-poles/

Solid sawn pressure preservative treated dimensional lumber or timbers.

Be wary of trying to recycle old treated wood if it has been treated with an oil based preservative:

https://www.hansenpolebuildings.com/blog/2012/11/pcp/

Structural joists and planks are lumber which is two to four inches thick and five inches and wider. These would include 2×6, 2×8, etc., as well as 4×6, 4×8, etc. Structural joists and planks are graded under a more stringent set of grading rules than either “Posts and Timbers” or “Beams and Stringers”.

Beams and Stringers are five inches and thicker, rectangular with a width more than two inches greater than their thickness. These would include dimensions such as 6×10 and 6×12.

Posts and Timbers are 5×5 and larger, where the width is not more than two inches greater than the thickness. Besides 5×5, it includes 6×6, 6×8, 8×8 and similar.

So isn’t a #2 grade a #2 grade regardless of size? Well, sort of…..larger pieces of lumber are given a #2 grade, with more defects (like larger knots). Correspondingly, the strength values are not the same. Using the measure of Fb (fiberstress in bending) and arbitrarily picking Hem-Fir as a species, a #2 6×6 has a value of 575, 6×10 is 675 and a 4×6 1105!

Regardless of the dimension of the lumber or species, proper pressure preservative treating is essential:

https://www.hansenpolebuildings.com/blog/2012/10/pressure-treated-posts-2/

Putting together individual pieces.

Multiple joists and planks can be joined to form a column, either spliced or unspliced.

In an unspliced scenario, building heights are normally limited to 16 feet, as generally it is difficult, if not impossible to purchase pressure preservative treated 2×6 or 2×8 in lengths longer than 20 foot.

I’ve discussed nail-laminated columns previously:

https://www.hansenpolebuildings.com/blog/2013/08/nail-laminated-posts/

Glu-laminated columns.

Some interesting glulam reading: https://www.hansenpolebuildings.com/blog/2014/04/titan-timbers/

Glulam PolesThese afford a Building Designer a plethora of structural options which cannot be achieved by the use of other alternatives. With a high strength to weight ratio, and typically being very straight – in markets where they are available, they can be a wonderful alternative, especially for taller buildings, or cases involving high wind and/or snow loads.

With so many options and alternatives, how is a consumer to know what poles are best?

My vote is for the overall design solution which best meets your individual needs for creation of space and access and egress. As long as the design is structurally sound and Code conforming, at the end of the day it does not matter what the individual pieces were used to build it.

Finger joints

The first time I was exposed to finger joints in wood and actually noticed them, was when I was working for Lucas Plywood and Lumber of Salem, Oregon in 1979 (yep, back in the Dark Ages).

I will digress momentarily….

My son recently turned 18, but when he was younger he had some interesting questions to ask of his Dad, whom he must have thought was very, very old. They included a couple of my favorites,

“Dad, was it exciting to watch the Space Aliens help build the pyramids?” and “What was it like playing Nintendo by candlelight?”finger-joint

Moving forward in the time warp machine….Virgil Lucas had made a deal with Weyerhaeuser to buy a bunch (defined as numerous truckloads) of finger jointed dimensional lumber 2x4s up to 2×12. Virgil was always one to look for a bargain, so I am sure the price was right. The Willamette Valley of Oregon was primarily a green lumber market, so the guys who had to throw loads together in the lumber yard were pretty excited to get to handle the light weight kiln dried finger jointed stock.

I never gave much thought to what was happening with finger joints themselves, until I worked as a field sales representative for a company which manufactured glue laminated columns for post frame buildings. It was then I began to realize what a huge science was actually happening, in such a small part of a given piece of lumber.

While splicing two pieces of wood together end-to-end might on the surface seem to be not such a big deal, the reality is that it has always been challenging and at times difficult.

Wood is strongest parallel to its grain. The problem is wood cannot be bonded sufficiently well end grain to end grain with existing adhesives and techniques. Wood can, however, be bonded quite effectively with most adhesives side grain to side grain. And generally quite easily.

The solution to being able to bond side grain to side grain (without overlapping two pieces of lumber) is the “finger joint”.

Finger jointing wood is not new. The automobile industry was using it a century ago for wood steering wheels and the spokes of wood wheels!

Finger joints can either be structural, or non-structural like the roaring 20’s automobile steering wheels. Nonstructural finger joints are used when strength is not a primary concern and where the goal is to remove natural, but unwanted defects in order to join shorter pieces of material into lengths long enough to be useful. Besides the steering wheel, other common examples are wood moldings, trim, siding, fascia boards, door jambs and window frames.

Structurally, finger joints are often seen in glue laminated beams and columns and the top and bottom members of I joists.

End-jointed structural lumber two inches or less in nominal thickness and up to 12 inches in width are accepted by the Building Codes as being interchangeable with solid sawn lumber. This acceptance is subject to the material having been manufactured under a certified program.

The geometry of the finger joint largely dictates it potential strength. Studies have found the thinner the “tips” of the fingers are, the stronger the joint. Longer “fingers” also produce stronger joints.

There are five basic steps to the manufacture of finger jointed wood products. They are: selection and preparation of the material, the forming of the joint itself, applying the adhesive, assembling the joint and curing the adhesive.

The portion of the wood to be joined should be free of knots or other strength-reducing defects. In most cases (and, as far as I know all) involving glue laminated columns for post frame buildings, the lumber being joined has been dried to a moisture content of 15% or less.

The actual forming (or cutting) of the fingers is critically important. If the fingers are too long, they will bottom out when pressure is applied and good contact between surfaces will not be obtained, resulting in a thick, weak glue line. If the fingers are too short, there will be gaps at the tips of the fingers which could result in excessive squeeze out of the adhesive.

Come back tomorrow and I’ll tell you how the fingers are made and glued together….in Part II of Finger joints.