Tag Archives: commercial girts

Insulate a Building, Truss Carrier Bolts, and Code Standards

This week the Pole Barn Guru answers reader questions about the proper way to insulate the walls of a metal building, advice on bolting truss carriers, and advice about, “building code standards for the horizontal infill framing” on a post frame building.

DEAR POLE BARN GURU: I would like to insulate the interior walls of a metal building so they could be finished with plywood or drywall so I could use the building as a cabin. The ceiling is insulated with fiberglass, but the walls are not. What is the proper way to insulate/frame the interior walls? BRIAN in COLUMBIA

DEAR BRIAN: The proper way would have been to have had your walls framed using commercial bookshelf wall girts https://www.hansenpolebuildings.com/2019/09/11-reasons-post-frame-commercial-girted-walls-are-best-for-drywall/.
You can still do this – using 2×4 #2 girts bookshelf style between the columns (hold girts flush to inside of columns).

I would recommend using rock wool batts, as they are unaffected by moisture https://www.hansenpolebuildings.com/2013/03/roxul-insulation/, with a well-sealed 6mil clear visqueen vapor barrier on the inside.

 

DEAR POLE BARN GURU: I am building a pole shed with 12′ side walls I have already poured a cement slab 10’x42′ next to the back wall I have installed [5] 6×6 poles with cement pads underneath them I am going to be measuring today for where to bolt on a truss carrier, do I measure 12′ up from the cement slab to mark where the truss carrier goes? TODD in ELK MOUND

DEAR TODD: Height of your truss carrier should be delineated on your engineer sealed, site specific, structural building plans. Typically, post frame buildings are measured by eave height, not ceiling height. https://www.hansenpolebuildings.com/2012/03/eave_height/

 

DEAR POLE BARN GURU: What are the building code standards for the horizontal infill framing between the posts of a post frame buildings, in terms of timber size, horizontal/vertical on center distance. I have seen 2x4s and 2x6s used, usually 24″ o/c vertically. Horizontally, how far can they span horizontally? JOHN in BANDERA

DEAR JOHN: Code requirement is wall girts must meet with minimum jurisdictional design criteria for wind speed and exposure (for reading on Exposure see https://www.hansenpolebuildings.com/2022/06/wind-exposure-and-confusion-part-iii/).
Deflection must be within limits specified in IBC Table 1604.3.

Externally mounted wall girts rarely meet deflection criteria https://www.hansenpolebuildings.com/2012/03/girts/
In most instances, bookshelf wall girts are a best structural design solution: https://www.hansenpolebuildings.com/2011/09/commercial-girts-what-are-they/
Ultimately, building from a fully engineered set of site specific plans will ensure your wall girts are properly designed to resist imposed loads.

 

Engineer Andy Ponders Insulation and Condensation

Engineer Andy Ponders Insulation and Condensation

Loyal (and prolific) blog reader ANDY in OXFORD writes:

“First, THANK YOU for providing so much valuable information in your blog, free of charge. I’m an engineer, quite handy, with construction experience. But everything I know about post frame construction, I learned from you. I’ve been planning for over a year, and I’ve read your first 1700 or so blogs. I’m about to place an order with Catherine Suarez, (she’s been very patient, by the way) for a 30x36x11. 6/12 roof with vented soffits and ridge, gable overhangs, and dripstop on roof steel. Location is north Mississippi, 30’s in winter, 90’s in summer with 60% to 80% humidity any time of year. It will be used as a dedicated woodworking shop, heated just above ambient in winter (except when I’m working there) and cooled only when I’m out there (rarely) in summer. I know you must get tired of insulation/condensation questions because you get so many of them. But it’s not something that’s intuitive to most of us. It’s the thing I’m least confident about. And I HATE rusty cast iron. I plan to install plywood or OSB ceiling with blown insulation above. House wrap between wall steel and girts (I would have never thought of house wrap), and craft-backed insulation between the commercial girts. Oh yes, and a good vapor barrier under the slab. So my question is . . . is this sufficient? What would Mike do??Thanks again for what you do.” 

Mike the Pole Barn Guru writes:
Thank you very much for your kind words, they are greatly appreciated. If I ever have to give a technical presentation on post-frame buildings, can I recruit you for my front row?

Post frame construction appears so simple at first glance, yet is highly technical and (like most things) it is in the details where they either work as expected or fall flat (literally). A set of calculations for even a simple rectangle can easily run over a hundred pages in verifying every member and connection!

Catherine is a dream. I love her clients as they know exactly what they are investing in and it makes for an extremely smooth process for all involved.

For some reason insulation and humidity are crucial areas seemingly left as an afterthought in far too many builds, often when it is too late to make economically sound corrections.

Lafayette County, Mississippi is in Climate Zone 3A (for reference). If you were building for a residence, 2021’s IECC (International Energy Conservation Code) would have R-49 ceilings, R-20 walls and R-10 slab perimeter insulation down two feet.

What would I do?

Even though you are probably not doing radiant in-floor heat, I would lay R-10 EPS insulation sheets on top of a well sealed under slab vapor barrier. If not, when it is 90 degrees F. and 80% humidity, the dew point is 83 degrees F. Your soil temperature could well be less than 70 degrees F., meaning you will have a damp floor from condensation.

For walls, a Weather Resistant Barrier and bookshelf girts are both winners in my book! I have become a proponent of rock/stone/mineral wool unfaced batts as they remain unaffected by moisture (and humidity) with a well-sealed 6mil clear poly vapor barrier inside. You have probably read this article: https://www.hansenpolebuildings.com/2013/03/roxul-insulation/

Ceiling – I do still like blown in fiberglass for value vs. return. I would specify 18 inch energy heel trusses to allow for full thickness of R-49 insulation from wall-to-wall, in conjunction with vented eaves and ridge.

You will want to make certain you order a well insulated and wind-rated overhead door for your woodworking shop. Keep in mind, door manufacturers do tend to stretch reality with their insulation claims https://www.hansenpolebuildings.com/2017/02/high-r-value-overhead-doors/.

Post Brackets, Cross Bracing, and Pressure Treated Wood

This week the Pole Barn Guru tackles reader questions about a building set into a slope with use of post brackets, the possible use of “cross bracing” for wall girts, and understanding pressure treated wood.

DEAR POLE BARN GURU: I would like to build a 32′ x 48′ 2 story pole building where two of the sides of at least the lower floor are at least partially set into the hillside on the property. I envision the two sides set into the hill to be concrete foundation walls. Sort of a daylight basement. The lower floor would be a woodshop and the upper floor a two bedroom apartment. I am assuming a concrete foundation with Laminated “poles” mounted in brackets as opposed to buried. the “poles” on the two sides set into the hill would be shorter than on the other two sides. With the available space, the two story concept works better than having everything on a single story. Is this even possible? What would a ROM cost for a kit like that cost?

Thank you BILL in WEST RICHLAND

DEAR BILL: Your idea is totally possible. I have done it myself. In my case I had 12 feet of grade change across my building’s 40 foot width. I used ICFs full height on one sidewall and stepping down across rear endwall. Columns on these two walls were mounted using wet set brackets, other two walls had embedded columns. This process could also be used with poured concrete or block walls. We have also developed a system to use columns placed in a permanent wood foundation.

Attached photo is of my own building.

This is being shared with your Hansen Pole Buildings’ Designer who will be reaching out to you shortly.

 

DEAR POLE BARN GURU: When using bookshelf girts is cross bracing used between posts or are the girts when blocked provide the support? WINSTON in MOULTON

DEAR WINSTON: No cross bracing is required when using bookshelf girts. Once installed (ideally blocked solid to columns at each end) and sheathing (OSB, plywood, structural panels or steel siding) is applied, your wall and girts are more than adequately supported and this assembly is fairly rigid.

 

DEAR POLE BARN GURU: I read the article regarding treated wood. I am still a little puzzled as to what treating you would use for ground contact purposes, especially the upright poles. Do you have any other articles regarding this subject or have input you could email me? Much appreciated, thank you. KELLY in VICTOR

DEAR KELLY: Pressure preservative treated wood standards can be confusing even for lumber dealers, professional builders and building inspectors. For structural building columns, all end tags should have UC-4B marked on them. UC-4B is for “Heavy Duty” use. This American Wood Preservers Association infographic might prove helpful to understanding proper uses for pressure preservative treated wood: www.awpa.com/images/standards/ResidentialInfographic2020.pdf

 

 

 

Builder Says

Builder Says, “These designs are the Worse”!

Like all good stories begin…..

“It was a dark and stormy night”

Oops, wrong beginning!

Once upon a time I was a post frame building contractor. From 1991 until 1999 my construction company could only have been described as being prolific – at one time we had as many as 35 crews erecting buildings in six states.

I had a few advantages going into being a post frame building contractor – architecture school, managing several (and later owning) prefabricated metal connector plated roof truss plants, and having provided nearly 7000 post frame building kit packages from my lumberyard.

mr owl tootsie roll popMy most important advantage was a thirst for knowledge. One of my favorite childhood books was 1967’s “The Way Things Work” by Neil Ardley and David McCaulay. I read it cover-to-cover repeatedly. This same thirst for wanting to know how things work led me to Dr. Frank Woeste at Virginia Tech. He challenged me with learning structural calculations involved in what made post frame (pole barn) buildings work.

This, in turn, led me to join ASAE (American Society of Agricultural Engineers) where I was a member of their structures committee. It also led me to be humble as I learned as I knew more, there was so much more to learn. I became an NFBA member – and found there was more than a single ‘right way’ to build post frame buildings.

Now it seems every small town in America has one or more post frame ‘builders’ and I will use this term ‘builder’ lightly as owning a jacked up 4×4, having a big dog and a loud stereo are not necessarily qualifiers for being a good builder. While there are actually some good builders (and a few great ones), far more a rule than an exception is “Chuck-in-a-truck” who believes he (or she) is Builder Bob – a legend in their own mind!

A Hansen Pole Buildings’ Do-It-Yourself client recently posted photos of their framed post frame building with commercial bookshelf girts.

Before being banned from the Facebook group for use of colorful language, builder Jason had this to say about this client’s photo:

“These designs are the worse! I don’t understand why anyone would do it this way. I really don’t understand why any company would promote such a design to a DIY. Book shelve wall girts are the weakest way to build building. All seams in wood is stacked. Not staggered. Toe nailed also is week. And if any system requires you to “hide” something or “never see it”, It’s a bad design! Just run wall girts on out side of post and stagger seams. Simple!”

Well Jason, not everyone has your narrow view of structural design solutions (or your grasp of English composition).

People (both builders and DIYers) do bookshelf girts because they are, at a minimum, over 300% stronger in supporting wind loads than externally mounted girts (based upon 2×6 material of same grade at same spacing). They are also more resistant to deflection by more than 1300%. Moreover, with proper dimensional sizing, they allow for creation of an insulation cavity where clients can do interior finishes without having to add more framing.

Jason appears to have a belief staggering joints on externally mounted wall girts somehow makes a building stiffer! It is the use of diaphragm design to create a stiff roof plane to support column tops making a building more rigid, not some close to insignificant contribution from girts. Our ‘builder’ went off on his rant before noticing the ends of each girt are solid blocked to columns at each end and no toe nails are involved in their fully engineered connection (nor was anything required to be hidden).

Thinking of hiring a builder to erect your new post frame building? Look for one who is open to considering multiple design considerations rather than “this is how we have always done it and always will”.

For extended reading on bookshelf girts please read: https://www.hansenpolebuildings.com/2020/04/creating-extra-work-in-barndominium-framing/

Creating Extra Work in Barndominium Framing

Creating Extra Work In Barndominium Framing

A supposed downside of post frame (pole barn) buildings for barndominiums is having to frame a wall inside of an exterior wall in order to create an insulation cavity and a way to support interior finishes.

This myth is created and propagated by post frame kit suppliers and post frame builders who do not understand there is a solution – and a very cost effective one (in both labor and materials).

Rather than framing exterior girts (as shown in photo) and then adding vertical stud walls between columns, bookshelf girts can be utilized.

I’ve done several thousand pole buildings using this “bookshelf” or “commercial” girt method. I have two of them myself – in Northeastern WA, so I have a cold climate to contend with.

Use a commercial girt one size larger than wall columns (2×8 on a 6×6 post, etc.), setting commercial girts so 1-1/2″ hangs past the column’s exterior face. Wrap framing with a well sealed high quality Weather Resistant Barrier (for extended reading on Weather Resistant Barriers https://www.hansenpolebuildings.com/2016/01/determining-the-most-effective-building-weather-resistant-barrier-part-1/). 

As an alternative to using a Weather Resistant Barrier, closed cell spray foam can be applied to the interior face of siding as part of a flash-and-batt system https://www.hansenpolebuildings.com/2020/01/flash-and-batt-insulating-barndominium-walls/.

You will find this installation method compensates for any irregularities in column dimensions and creates a deeper insulation cavity. Side benefits – electrical can be run around column exteriors, without a need to drill through them to run wires. On walls a multiple of three feet in length, it also saves having to rip an edge of a panel off either the first or last sheet of steel on a wall.

In either case, block ends of bookshelf commercial girts solid against columns with what is called a “bearing block”.  Take 2×4’s or larger (depends upon engineering) cut 22-1/2” long to fit between commercial girts and install them flat against the post on faces where girts will attach.  Wide face of the block should be flat against the column and aligned with the post edge (not sticking out past column edge unlike girts).   Nail these girt support blocks to columns with a minimum of  two (2)10d galvanized common nails at each end (higher wind loads may require more nails).  This type of nailing is quick and easy and provides a solid support for commercial girt above blocks.  This is a far more solid and stable connection than toe-nailing. Toe-nailing is done by angling a nail upwards from bottom (or downwards from top) of commercial girt, at a 45 degree angle trying to catch enough post edge as the nail goes through to column to hold it there.  Toe-nailing is a very poor connection (and is subject to lots of installation errors).

For maximum cost effective R value, use BIBS insulation. I found it to be cost competitive with installed batt insulation, has a higher R value and completely fills all voids. https://www.hansenpolebuildings.com/2011/11/bibs/

I fondly remember a gal who called me one day asking for “canning jar shelves”…you know like you did before for us.”  Checking our records, I quickly discovered we designed commercial girts on their first building.  They liked them so much – they wanted them again!

Planning for Lighting in a New Pole Barn

Both of my post frame buildings outside of Spokane, WA have no windows on the garage/shop level. This means when inside, with doors closed, it is dark – one is forced to rely upon electricity or radar to navigate.

Reader KRISTI is preparing to build her new pole barn and had some questions about how to light up her life:

“Hi there!

I plan to have a 36’x40’ pole barn built before the cold weather hits here in Michigan and I have a couple of quick questions if you don’t mind. 

First, I will be using this building as workshop so it will definitely be insulated and heated. I’m planning to run a radiant slab heat system. My first question is regarding windows. I want to be able to see outside but more importantly, I want all the daylight I can get! That in mind, which wall would you recommend to bring in the most light? How do I frame up the interior walls around the windows? How difficult is it to add windows once the insulation and sheathing is done inside? Lastly, would you recommend using clear acrylic panels along the tops of the walls? I’m a little worried it will yellow over time & I’m not sure how I could insulate the acrylic if it’s even possible. 

The barn will be in an open area with little to no shade & will have a large garage door on the east end, and 12’ walls with a ceiling. 

Thank you in advance for any time you should spend on answering my questions! I totally understand if you are too busy to indulge me and if I could only ask one question I would ask how to frame out the interior walls for a window. 

Thanks again!”

Mike the Pole Barn Guru responds:

Gambrel roof pole barnTo get the most light, place windows on the south wall. Easiest way to frame your exterior walls (interior walls around windows) is to use what we refer to as commercial girts (https://www.hansenpolebuildings.com/2011/09/commercial-girts-what-are-they/). Once you have finished insulating and an interior wall covering, there will be an extreme degree of difficulty to add more windows – it is best to plan for them in advance and install at time of initial construction. This also allows for them to be incorporated into engineered building plans as increasing openings. Without engineering, can compromise the structural integrity of your building. While eave light panels are very effective for unheated buildings, in your case you would be heating much of Michigan, if you used them. Here is some more reading on light panels: https://www.hansenpolebuildings.com/2014/02/acrylic/.

We will be looking forward to helping you with your new pole barn!

When a Contractor Ignores Building Plans

I realize this may come as a surprise, but there are more than a few times I have discovered building contractors have made errors in building assembly due to failure to examine the provided building plans.

Shocking.

Our client STEVE in HINES writes:

“Good morning, my building is framed, sided and roofed. However, yesterday we discovered that the sidewalls girts should have been 2x 8’s but 2×6’s were used instead (same as the endwalls). I know this is my problem to fix, but before I tell the contractor, I’d like to know if you have ever heard of this happening and if so, what they had to do to fix the problem. As it stands, it definitely does not meet wind code anymore. I’m not asking for a fix, but only some direction as where to start pursuing one. Could very well become a messy job!

Thanks.”

Well, to begin with, I was a post frame building contractor in a past life. At times we had as many as 35 crews erecting buildings in six states. Most of these crews were very, very good. Some of them were not quite as good. Overall this mix did give me an interesting perspective – if something could be done wrong, one of my crews figured out how to do it. Along with this, chances are I have had to come up with a fix for these unexpected challenges.

In Steve’s case, actual reasoning for 2×8 sidewall girts was so his building could have a flush interior surface to drywall – known as commercial girts. (Learn about commercial wall girts here: https://www.hansenpolebuildings.com/2011/09/commercial-girts-what-are-they/)

Our curiosity question was – what did the builder do with the 2×8 material supplied for girts? It turns out client had a pile of 2×8 left over when the pole building was completed. They ran short of 2×6, so building owner just assumed someone had stolen them and more were purchased!

Anyhow – there are several possible fixes. 2x4x12′ could be ripped and nailed along length of  2×6 installed where 2×8 should have been, or 2×4 could be placed vertically (3-1/2″ face against girt inside face) every two feet’ to provide a surface to attach drywall. Whichever choice is decided upon, a revision should be done to plans and sealed by Engineer of Record to verify adequacy.

Making Framing Work With Bookshelf Girts

Making Framing Work With Bookshelf Girts for Insulation

A most simple method to achieve a deep insulation cavity in post frame building walls is to use bookshelf girts, but how to make framing work?

Some quick background reading on commercial girts: https://www.hansenpolebuildings.com/2011/09/commercial-girts-what-are-they/.

Reader BRANDON in ST. JOE got today’s discussion going when he wrote:

“Hi there. I’m going to be building a post frame house and got a quote form Hansen for my building. Question is with the bookshelf Girts if they are 2x8s which measures 7 1/4” on 6×6 post that is 5 1/2” plus your 1 1/2” grade board will you notice the 1/4” difference.”

In an ideal dream world every 6×6 column would measure exactly 5-1/2 inches square. However lumber comes from trees, and trees are organic and tend to have a certain degree of variability. Rarely are timbers going to be dried after being milled, other than by nature. As such, they most usually start off being cut slightly over-sized in order to allow for shrinkage hopefully ending up with a 5-1/2 inch dimension.

I have seen builders attempt to use 2×6 bookshelf girts with 6×6 columns, if posts are perfect dimension then both sides can be set flush and surfaces for siding and interior finish are smooth. It does involve some extra work insetting things like splash planks, eave girts, headers, etc., as well.

I tried this in my own garage I had built in 1991. My posts were not perfect dimension, they were big! I had to stop drywall up against each column and then texture over posts. Trust me, it was a PITA (Pain In The Axx).

An easy fix – oversize girts by one dimension, using a 2×8 with a 6×6 column as an example. Chances are excellent columns will measure 5-3/4 inches in depth or less. If less, drywall (or other interior finish such as OSB or plywood) can be run directly across thinner columns with no adverse challenges.

I would recommend using closed cell rigid insulation sheets inside of framing, behind drywall, to create a thermal break.

Plans only? Girts Placed Correctly, and Sheeting

Engineer sealed pole barnDEAR POLE BARN GURU: Hi, do you sell pole barn plans without material kits? I’m interested in pricing a set of plans from you and procuring my own materials. If that’s a service you can provide please let me know. I’m looking to get a plan set for a 40’x45′ pole barn.

Thank you, DAMIEN in PORTLAND

DEAR DAMIEN: Here is an article with all of the information you will need: https://www.hansenpolebuildings.com/2017/06/pole-building-plans-sale/

 

DEAR POLE BARN GURU: my side wall columns are 4 ply 2×8’s and are a little over 7″ deep. My commercial girts are 2×10’s(9.25″). The girts are extended past both the skirt board and the 2×4 at the top of the wall by 2.25″-1.5″=0.75″.> How is this supposed to work? RICK in LUCEDALE

DEAR RICK: Place the girts so the outside of the girt is 1-1/2″ past the columns, any excess will be to the inside. When you sheetrock, the drywall will be attached to the girts and go right over the columns. See Chapter 29 of the Hansen Pole Buildings Construction Manual, most common mistake #4.

 

DEAR POLE BARN GURU: Does a residential pole barn home require exterior and roof sheathing? And if not required, would you recommend osb or plywood sheathing?
Thank you, JOE in SANDY RIDGE

DEAR JOE: If the siding and roofing are both roll formed steel panels, then no other sheathing would be required, unless the load situation is such as to require sheathing under the steel for shear resistance purposes. You should, however, be using Building Wrap under the wall steel and make some sort of provision for condensation control under the roof steel (either a radiant reflective barrier, sheathing with 30# felt, Condenstop/Dripstop or closed cell spray foam as examples).

As far as product – unless you are counting upon the sheathing being the holding point for the screws, OSB will do everything you need it to do.

 

Bookshelf Girts for Insulation

In the land where I first became acquainted with pole barn (post frame) building construction, was used a term known as commercial girts. These are actually what is more appropriately named “bookshelf girts” designed so as to create an insulation cavity which would extend 1-1/2 inches outside of the columns. The commercial girt is sized so the wall columns do not project inside of the plane of the bookshelf girts. An example would be using a 2×8 girt on 6×6 columns.

Reader Matt in Poland writes:

“Hi Mike, I didn’t come across your blog until after we purchased our pole barn package (not from Hansen) and were getting started. Our mistake, but we have learned so much from your blog.

My question is around the “illusive” commercial girts aka Bookshelf girts. When I say illusive, it is because, there are only about 2 internet postings about them, both belonging to you. We put standard 2×4 girts on the outside with Housewrap then metal. Now we are working on starting the interior and are going to go with 2×8 commercial girts inside. My question is running exterior wall things such as some plumbing, Gas lines etc. I do understand the electrical can run down the face of the post and has a 1 1/2 channel to do such, but what about those other things for rough-in.

We have taken a lot of pictures, and hope to post more information about our current build so that others can hopefully gleam information too.

Thanks Matt”

Matt’s kind words are of course much appreciated. The Hansen Pole Buildings’ “Ultimate Post Frame Building Experience™” is crafted with the idea of delivering the best value post frame building kit package to best meet with the ultimate needs of the client. In the case of Matt, it sounds as though his particular supplier may not have asked enough questions to have truly given to him the best design solution.

I will surmise Matt’s building has 6×6 columns with 2×4 “flat” girts placed on the exterior of the wall columns. As the bookshelf girts are being used to provide a surface for interior finishing only, it is possible a girt size as minimal as 2×4 could be used, holding the girt flush to the inside of the columns. Not only would this prove to be a greater cost savings, it also eliminates the transfer of heat and cold through girts which would touch both the exterior and interior finish surfaces. This type of interior commercial girt only needs to be stiff enough to resist undue deflection of the gypsum wallboard. This deflection limitation is to prevent taped joints from cracking.

As much as possible plumbing should not be run through exterior walls, especially in climates where freezing is possible during winter months.

The are some Building Code limitations as to the size of holes which can be drilled through sawn lumber, this excerpt is from the IRC (International Residential Code):

IRC R802.7.1 Sawn lumber.

“Notches in solid lumber joists, rafters and beams shall not exceed one-sixth of the depth of the member, shall not be longer than one-third of the depth of the member and shall not be located in the middle one-third of the span. Notches at the ends of the member shall not exceed one-fourth the depth of the member. The tension side of members 4 inches (102 mm) or greater in nominal thickness shall not be notched except at the ends of the members. The diameter of the holes bored or cut into members shall not exceed one-third the depth of the member. Holes shall not be closer than 2 inches (51mm) to the top or bottom of the member, or to any other hole located in the member. Where the member is also notched, the hole shall not be closer than 2 inches (51 mm) to the notch.”

This would allow for a hole of up to 1-13/16 inches to be bored through a 6×6 column, without adversely affecting the strength of the column.

Planning on climate controlling your new post frame building? Discuss the options with your Hansen Pole Buildings’ Designer to arrive at design decisions which will best meet your needs today, as well as in the future.

Why Not Use T Girts?

Last August one of our clients in Colorado invested in a new Hansen Pole Buildings Monitor style building. One of the features of the building was for it to be drywall ready. The
typical method we use for this is what we refer to as “commercial” girts – basically they are bookshelf style girts, set 24 inches on center, sized to match the columns and it includes a pressure preservative treated mudsill to set on top of the concrete floor, as well as the necessary backing at the top of the wall to support drywall.
For more reading on commercial girts: https://www.hansenpolebuildings.com/2011/09/commercial-girts-what-are-they/
This particular client is in an area where the design wind speed is 115 mph (miles per hour) and this particular site has an Exposure C.
Learn everything you ever wanted to know about wind exposure and then some here: https://www.hansenpolebuildings.com/2012/03/wind-exposure-confusion/
It turns out or client hired a perhaps less than qualified builder to construct his building, and along the way had to dismiss him and find a replacement builder.
Keep in mind, the modern Hansen Pole Building is the result of input from people who have collectively constructed hundreds of thousands of buildings. Our team here is always “ears open” to ideas which make for a better building, without adding astronomically to the investment.
This is part of the culture of delivering the “Ultimate Post Frame Building Experience™”.
New builder made this suggestion:
“If you are open to suggestions, the next time you sell a building such as this and the buyer wants to finish the inside, use 2×6 wall girts laying flat in between the post and a 2×6 wall girts attached to the outside of the post , nail them together in the shape of a T. It would cost less, be stronger, easier and faster to build.”
Let’s see if new builder is correct in his recommendation.
On this particular building, the sidewall columns are 3 ply 2×8, which requires a 2×10 commercial girt. To make builder’s suggestion work, it would take a 2×6 on the outside of the column and a 2×8 placed bookshelf style.
For sake of pricing discussion, I have used numbers from the closest The Home Depot® to the client, which is in Colorado Springs. Our version (the 2×10 10 feet long) weighs in at $10.93. The builder’s version (a 2×6 and a 2×8 10 feet long) come in at $6.37 and $8.46 for a total of $14.83, so certainly not less expensive in the materials portion.
Looks to me like the builder’s less expensive version comes in at over 35% more expensive!
How about strength?

The combined 2×6/2×8 mix has a Section Modulus of 15.203. while the single 2×10 is 21.3906. Now the combined mix gets to use a base Fb (Fiberstress in bending) value of 1020, the 2×10 only comes in at 935. Doing the math the combined method is 15.203 X 1020 = 15,507 in-lb, the single 2×10 21.3906 X 935 = 20,000 in-lb.
Hmmmm – the building as designed would have wall girts nearly 29% stronger than the builder’s “stronger” method.
How about easier and faster to build?
Well, it now involves having to cut two boards and nail them together as a T, rather than cutting and installing a single board. Not seeing how this is faster.
Unless – builder is thinking he will not have to place blocks under each end of the bookshelf girt.
The suction force on the end of each of these wall girts amounts to 258.25 pounds. I don’t know what the builder was planning upon using for nails, but with the recommended 10d common nails, the withdrawl value is somewhere around 37.5 pounds per nail. Factoring in the DOL (Duration of Load) factor for wind, this would amount to having to place 5 nails into an area roughly two inches by five and one half inches.
Could it be done? Maybe, but methinks it will result in a poor result – both cosmetically and structurally.
In addition, with no block under the ends of the 2×8 bookshelf girt it is going to be prone to some twisting issues.
Suggestion appreciated, however the verdict, in this case, is a resounding no.

Bookshelf Girts aka Commercial Girts: What Are They?

Bookshelf Girts aka Commercial  Girts: What are they?

I do a lot of blogging, not because I enjoy it (which I do) but because I am always “listening” and learning.  And if there is anyone out there who I can help along the way, my fun increases exponentially.  I recently came across this posting on a Farm Forum:

Commercial Wall Girts

I am going to build a new shop building and wish to be able to finish the inside, insulation, sheeting, etc. I am in Minnesota, so it has to be fairly energy efficient. I saw some brief info on the “bookshelf method” in a pamphlet I picked up from a store. Looks like a super way to provide the desired structure on the inside of the wall surface to fasten sheeting to, and provide spaces for fiberglass batts laid in there horizontally. Very material efficient method, I believe. If anyone here has used this method, please share your experiences with it, pictures too if possible. Even if you have seen one built, like by a neighbor or friend, please speak up and share.
In case you do not recognize the method by the name I gave it (bookshelf), it is a technique which puts the wall girts between the posts, laid flat, typically 2×6’s, 24 inches on center vertically spaced (instead of the usual girt method which puts them on the outside of the posts). The pamphlet says they can be toe-nailed (?) or little nailers installed above and below them, for fastening to the posts. The pamphlet says wind loading is increased with the bookshelf method. The real attractive part of this method for me is that the 2×6 girt is available to the outside tin for fastening, then provides a 22.5 inch tall space for fiberglass bat (off the shelf size for between trusses on 24 inch center) and then is flush to the inside of the wall for interior wall sheeting fastening.
Thanks.

I’ve done several thousand pole buildings using the “bookshelf” or “commercial” girt method. I have two of them myself – in Northeastern WA, so have cold climate to contend with.

Use a commercial girt one size larger than the columns (2×8 on a 6×6 post, etc.), setting the commercial girt so 1-1/2″ hangs past the exterior face of the column. Wrap the framing with a well sealed high quality building wrap.

You will find this installation method compensates for any irregularities in the column dimensions and creates a deeper insulation cavity. Side benefits – electrical can be run around the outside of the columns, without the need to drill through them to run wires. On walls which are a multiple of 3′ in length, it also saves having to rip the edge of a panel off either the first or last sheet of steel on the wall.

In either case, block the ends of the bookshelf commercial girts solid against the columns with what is called “bearing blocks”.  Take 2×4’s or larger (depends upon engineering) which are cut 22-1/2” long to fit between the commercial girts and install them flat against the post on each side.  The wide face of the block should be flat against the column and lined up with the edge of the post (not sticking out past the column like the girts are).   Nail these girt support blocks to the columns with a minimum of (2)10d galvanized common nails at each end (higher wind loads may require more nails).  This type of nailing is quick and easy and provides a solid support for the commercial girt above it.  Toe-nailing is done by angling a nail upwards from the bottom (or downwards from the top) of the commercial girt, at a 45 degree angle trying to catch enough of the edge of the post as the nail goes through to the column to hold it there.  Toe-nailing is a very poor connection (is subject to lots of installation error).

For maximum cost effective R value, use BIBS insulation. I found it to be cost competitive with installed batt insulation, has a higher R value and completely fills all of the voids.

I fondly remember the gal who called me one day asking for “canning jar shelves”…you know like you did before for us.”  Checking our records, I quickly discovered we designed commercial girts on their first building.  They liked them so much – they wanted them again!

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