Tag Archives: ACQ treated lumber

Termite Barriers and Wind Speed, Hidden Fasteners, and Truss Modifications

This week the Pole Barn Guru tackles reader questions about termites that can destroy treated lumber in an area wind 80mph winds, if one can install a roof with hidden fasteners over trusses or if it needs an underlayment, and the possibility of modifying a truss chord in order to accommodate a overhead door operator.

DEAR POLE BARN GURU: We have terrible subterranean termites that can destroy treated lumber. We also live in an area that sees 80 mph winds in the winter. Are your pole barns strong enough to withstand these things? DAN in FRAZIER PARK

DEAR DAN: Every Hansen Pole Building is fully engineered to meet or exceed your jurisdiction’s minimum design wind speed requirements (in Ventura county Vult = 100 mph). When wind is a client concern, we always recommend designing to higher than minimum design wind speeds. In many instances, added investments are minimal. Most important is designing to correct wind exposure for your particular site. Most other providers sell Exposure B rated buildings, when many sites are actually Exposure C. For extended reading on wind exposure, please read: https://www.hansenpolebuildings.com/2022/06/wind-exposure-and-confusion-part-iii/ While our buildings come with any pressure preservative treated wood at or above Building Code requirements. Regardless of structural building system in areas prone to subterranean termites treat prepared soil with a termiticide barrier at a rate of one gallon of chemical solution per every 10 square feet.


DEAR POLE BARN GURU: I want hidden fastener steel roof, do I need to sheath the roof or can I install over trusses. Also, how far apart are your trusses for residential pole barn homes? JAY in MILWAUKEE

DEAR JAY: Hidden fastener steel should only be installed over solid sheathing as it has no shear value to be able to transfer wind loads from roof to endwalls. https://www.hansenpolebuildings.com/2015/08/standing-seam-steel/

In most instances, our fully engineered post-frame barndominiums are designed with a pair of trusses directly aligned with columns every 12 feet.


DEAR POLE BARN GURU: Would it be possible to install a 1/8- 1/4 ‘’ steel plate C-shaped with a “tail” extending from back side to tie a bottom chord and king post together and then cut out a 6’’ section to allow for a garage door opener install. GABE in SIMCOE

DEAR GABE: Maybe, however no truss should ever be cut or modified unless done with an engineer certified repair. https://www.hansenpolebuildings.com/2016/07/cutting-trusses/



Site Prep, Brackets on Slab, and Treated Lumber

This Wednesday the Pole Barn Guru answers reader questions about site preparation and underground obstructions, a recommendation for building with wet set brackets on slab, and whether or not Hansen Buildings uses lumber treated for in-ground use– UC-4B.

DEAR POLE BARN GURU: We recently started the ground work for our future 48×72 pole building. Half way through excavation the crew hit a solid slab of rock at the corner of our building site. It appears to be Pennsylvania blue stone and the space that it takes up includes a majority of the back and left side where the building walls would sit. We were able to achieve a level pad but we are extremely concerned that now we won’t be able to build on this site. This is the only place on our property that has room for this build and we are very worried that we won’t be able to set poles in the ground do to the size of this solid slab. What are our options, if any? KIMBERLY in PENNSYLVANIA

DEAR KIMBERLY: This brought back childhood memories of my Dad taking me out on a Saturday to a site above Hayden Lake, Idaho where he and my uncles were going to be framing a custom home. Site had been cleared, and there were all sorts of roughly inch and one-half diameter holes drilled into solid rock – they had to blast in order to get a foundation in!

You do have many options, however blasting can be (I have found) quite affordable. Many years ago we built a horse stall barn near Benton City, Washington. This building had a total of 84 columns and was on a rock shelf. Powder monkey came out and blasted all of them for a couple of hundred dollar bills!

There are other choices – you can rent a “ram hoe” attachment for a skid steer or backhoe (this would probably be my pick). Read more here: https://www.hansenpolebuildings.com/2016/12/attacking-pole-barn-rocks-holes/

Or, a jackhammer – I would not suggest this option for more than just a hole or two.


DEAR POLE BARN GURU: I am in the planning stages for a pole barn build. The building will be 50 ft wide by 40 ft deep by 16 ft high at the eaves, posts spaced at 10 ft centers. This will go on a concrete pad and I am looking into using Sturdi-Wall Plus wet set brackets. My question is in regard to the height of the posts (roughly 16 ft) and the bending moment loads (wind loads) on the side of the building. Have you designed/installed posts with this height or higher before? If so, is there a place where I can point the planning officials to that shows the calcs and what not so they can make a decision as to whether or not this type of application with my situation will work or not?

I appreciate your help! MICHAEL in UPTON

DEAR MICHAEL: Thank you for reaching out to us. We have provided fully engineered post frame buildings using these very same brackets and eave heights of 24′. Your real solution is to have your building plans done by a Registered Professional Engineer who can provide verifying calculations for all components and connections.


DEAR POLE BARN GURU: I have a question about the structure of your pole barns. Do you use treated lumber or non treatmented lumber? I am asking about the post that go in the ground AND the boards that touch the metal roof. I worry about the wood rotting or bugs getting in it. KRISTEN in BAY MINETTE

DEAR KRISTEN: Any roof supporting structural columns are pressure preservative treated to UC-4B per International Building Code requirements. This is a greater level of pressure treatment than you can usually find at big box stores or local lumberyards. Any other lumber used in ground contact will be treated to UC-4A and tags will reflect ‘ground contact’. Lumber in contact with steel roofing (roof purlins) are not exposed to the weather, would not typically be pressure preservative treated. We do always recommend a condensation control be used between roof steel and roof framing. The easiest, from an application standpoint, would be a factory applied to roof steel Integral Condensation Control (DripStop or CondenStop). Other alternatives would be a Radiant Reflective Barrier (we can provide this in six foot width rolls with an adhesive pull strip attached for ease of joining rolls together) or to use two inches of closed cell spray foam.


Isolating Truss Connector Plates from Treated Lumber

Isolating Truss Connector Plates from Treated Lumber

Assembly time for Hansen Pole Buildings’ client BRAD in MOUNT VERNON. Construction has begun upon his new post frame building. Brad had some great questions for Technical Support!

“I’m not sure if you can answer my question or can possible point me in the correct direction.  We are about to attach trusses.  I thought that I had read somewhere that we needed to isolate the truss connector plates from the treated poles, if they were in a position where they would contact the columns.  Also, is it OK to fasten through these connector plates?

Thank you for your time and help on all of the questions we have had so far.”

Mike the Pole Barn Guru responds:

This Construction Manual caution regards ACQ pressure preservative treated lumber only. Each piece of pressure preservative treated lumber will be marked or tagged with an identification of chemicals used for treatment (as well as level of treatment).

 Truss plates are produced from sheet steel which is galvanized to ASTM A 653 specifications. The galvanized coating is suitable for use with non-corrosive lumber treatments, including most sodium borate-based preservatives.

  This galvanizing is not suitable for direct contact with ACQ treated lumber. A waterproof barrier, such as polyethylene roof underlayment (Vycor or similar), must be placed between any truss plates and ACQ treated lumber. An application example is where the truss heel is attached to a treated wood post. The entire truss plate must be covered with barrier, and care shall be taken not to rip or damage barrier when drilling or installing any fasteners.

  In lieu of a waterproof barrier, exposed truss plate surface may be painted as recommended by ANSI/TPI 1-2002 Section 6.51:

Epoxy-Polyamide Primer (SSPC-Paint 22)

Coal-Tar Epoxy-Polyamide Black or Dark Red Paint (SSPC-Paint 16)

Basic Zinc Chromate-Vinyl Butyral Wash Primer (SSPC-Paint 27) and cold applied Asphaltic Mastic (Extra Thick Film) Paint (SSPC-Paint 12).

Keep in mind we, as manufacturers, have to deal in a perfect world where everyone follows everyone else’s rules of best practice and instructions. I’d like to tell you as long as you keep this connection dry, you are highly unlikely to ever have an issue, however there still exists a rare possibility.

If location of a steel connector plate happens to make it impossible to otherwise fasten a truss, place fasteners so they go through “holes” in truss connector plate. BCSI-B8 addresses a similar issue of connectors being placed through a truss plate, “Toe-nailing through a metal connector plate of a truss does not adversely affect the uplift capacity of the Connection provided the truss plate and lumber are not damaged during installation.” https://www.sbcmag.info/sites/sbcmag.info/files/article/2007/01/bcsi_chapter_8_pdf__15339.pdf.

Of interest, some metal plate connected wood truss manufacturers use nail guns to set steel plates, prior to trusses being pushed through a roller press, setting them permanently.