Tag Archives: closed cell spray foam

Net Zero Post Frame Homes

Net Zero Post Frame Homes

Energy efficiency has become a huge focus in every type of home construction. Post frame homes can be net zero, just as well as stick frame.

Our environmental commitment allows us to design post frame homes to reduce environmental impact. High performance design and advanced engineering make it easier and more attainable to build a home producing as much energy as it needs through renewable energy, known as net-zero energy.

A net-zero home will be more than a house with solar panels. It’s a house designed to put energy conservation first: from framing to finishing. An airtight structural shell paired with additional options – such as highly insulated wall systems, high performance windows, passive solar design and more – mean any Hansen Pole Buildings’ post frame home can be designed to achieve net-zero energy.

Reader IAN from MIDDLETON writes:

“Mike-

First, I want to let you know how much I have enjoyed reading your blog. I started reading through it topically to answer some of my questions, but because I have been finding so much good information, I resolved to start at the beginning and read through chronologically to make sure I don’t miss anything. Thank you for sharing your lessons learned from decades of experience.

I’ve been exploring options for a cost effective and energy efficient single family home. Reading on your blog has convinced me of the advantages of post frame construction, but I have also been reading about ways to achieve high energy efficiency. In particular, I’m interested in ways to incorporate thorough air sealing and extra insulation (in particular for walls) into a post framed structure. I have found numerous references on the internet to the ways that post frame construction is generally moderately more energy efficient that stick framing, but I have only found a few examples that specifically address trying to achieve a very high level of energy efficiency in a post framed house. The clearest example I’ve found is the following short video that profiles the construction of a net zero single family home in upstate New York: https://youtu.be/PKXNwdvUNj4

My questions for you:

Have you designed a post framed home with high energy efficiency in mind? What kinds of strategies did you use to achieve high energy efficiency?

Have you ever designed a super-insulated post framed home, and if so, how did you incorporate the additional insulation? Some approaches used in stick framing are double stud exterior walls, or supplemental rigid foam insulation between the sheathing and siding (likely not ideal for a steel clad post framed building). Have you seen these or other super-insulation strategies used on post framed buildings?

Finally, have you ever had a post framed home blower door tested for airtightness, if so, how did it perform? Do you have any recommendations for air sealing strategies specific to post frame construction?

Thank you for considering my questions; keep up the good work!”

Thank you for your kind words. Sadly, most post frame home clients are just not savvy enough to be willing to make an extra upfront investment to super insulate their buildings.  I have designed several post frame residential buildings for my own use, so I have learned from mistakes. Also, technologies have improved greatly in recent years, making energy efficient designs more practical.

For walls, my current best recommendation would be to use two inches of closed cell spray foam against siding insides. Walls would be framed with bookshelf style girts to create a deep insulation cavity. BIBs insulation would be used to entirely fill the wall cavity. Inside of the  girts, covering columns as well, two inches of rigid closed cell foam board would be applied with glue, and all seams sealed. Gypsum wallboard (sheetrock) would be then glued to the foam board. Using rigid foam board inside eliminates any thermal bridging as well as creating a vapor barrier.

With 2×8 bookshelf girts, a wall system of over R-50 could be obtained using description above.

I am not yet sold about creating a warm attic – so I’d use 22 inch raised heel trusses and blow in 20 inches of fiberglass to go R-60 and beyond.

I haven’t seen any post frame air tightness tests, however even 25 years ago (when I was building post frame buildings) we had instances where our post frame homes and commercial buildings were so tight, a window had to be opened in order to close exterior entry doors!

Good Luck! And let me know how it all turns out. I’d love to see pictures of your progress!

 

Will My Post Frame Building Support a Ceiling?

Will My Post Frame Building Support a Ceiling?

One of my frequently received questions – wanting to add a ceiling into a post frame building and wondering if the building will support the added weight. Other frequent questions include condensation issues and ventilation, so this reader has hit upon a trifecta.


Reader BRYAN in SWANTON writes:

“I am having some condensation issues. And I was curious about insulating the building. Also wanted to ask if my building is able to have a ceiling installed. Thanks for the fast reply.”

 

 


By any chance have you recently poured a concrete slab-on-grade inside of your building? If so, until concrete fully cures, it will expel a great deal of moisture inside of your building. Solution – open your doors to allow moisture to escape and keep them open until condensation issues no longer exist. Read more here: https://www.hansenpolebuildings.com/2018/01/condensation-roof-steel/.

 

If you poured a slab without a well-sealed vapor barrier underneath, it will contribute to excessive moisture challenges. If no vapor barrier, top of slab should be sealed: https://www.hansenpolebuildings.com/2018/11/siloxa-tek-8505-concrete-sealant/

 

Your new post frame building and its trusses were not ordered to be able to support the added weight of a ceiling. It may be possible to upgrade your trusses with an engineered repair to be able to carry a bottom chord dead load of five psf (pounds per square foot) or more. Plan upon an investment of $295 (plus sales tax if applicable), even if a truss repair cannot be designed. Contact Justine at justine@hansenpolebuildings.com if you are interested in going this route.

If you are able to get a repair to install a ceiling, this newly enclosed attic area will need to be adequately ventilated. This may be a possible solution: https://www.hansenpolebuildings.com/2018/07/my-pole-barn-needs-ventilation/

In order to insulate, best solution (although costly) may be to use closed cell spray foam insulation. If you purchase an insulation kit for your overhead door, you will need to change out door springs in order to handle the added weight.

 

 

Avoiding Condensation When Insulating an Existing Pole Barn

Avoiding Condensation When Insulating Existing Pole Barn

The last thing people want to have to deal with would be condensation dripping in their pole barn. When an originally unheated cold storage building becomes repurposed to be climate controlled, possible condensation poses some new challenges.

If you are reading this article and plans are to construct an unheated building, I implore you to consider taking steps so it could be repurposed to be heated and/or cooled later. Please browse through some of my previous articles regarding this subject, such as: https://www.hansenpolebuildings.com/2018/06/pole-barn-insulation-oh-so-confusing/.

Reader JOSEPH in ALPINE writes:

“We have a pre-existing pole barn that we want to turn into a insulated building. Knowing that condensation would be a problem, I’m looking for a professional to consult with so it is done correctly. Is this something you do and what are your rates?

 

The building is 15×15, on a pad. There is no attic- 1/4” plywood is nailed to the ceiling 2x4s. We’d like to keep this height since it affords space for a loft. There is a single central roof vent. I read your response to one customer about using unbatted insulation on the walls and punching holes in the plastic to allow venting. But how does one allow for venting when there is no attic space? Our main house (1937 farm home, remodeled to modern code in 2003) is a metal roof with the upstairs rooms opened up, no attic, no roof vents. How can one replicate what is done in the house with this pole barn?

Thanks.”

Mike the Pole Barn Guru writes:

I am deeply flattered to have someone offer to hire me for a consultation. Here is my response to Joseph:

I am a bit geographically inconvenient to be able to come and see your building. However, based upon experience and what I would do if it was my own building, I will give you some free advice. You are welcome to use it, or discard it as best you see fit.

As you do not know if a vapor barrier exists beneath your existing concrete slab, I would use a high quality surface sealant over it. Your major water source for potential condensation will be through this slab. I’d close off roof vent, and have inside surface of siding and roofing closed cell spray foamed. Your local installers can give you recommendations for thickness, however I would not go with less than two inches thickness. If possible or practical, unfaced fiberglass insulation may be added to the inside to increase R value. However, it might be most practical to just pay a little extra for thicker spray foam.