Replies

1. 
   Rick Van Handel|Sep 30, 2015 09:44pm|#1

   A pole building will not be very efficient as the opportunity for air leaks are very high. Think about how you will air seal the intersection between your floor and your outside wall. If you do the commercial girts approach you'll have significant thermal bridging at your poles. The steel outer skin will prevent drying to the outside also.

2. 
   Steven Gubkin|Sep 30, 2015 10:09pm|#2

   I have no building experience at all.

   I assumed I could air seal the intersection of the floor and outside wall with more cob?

   I was thinking maybe commercial girts, but with some kind of double wall system to prevent thermal bridging at the poles?

   Is there a reason I will need a steel outer skin?

   I am really hoping more for resources which detail energy efficient pole building practices.

3. GBA Editor
   Martin Holladay|Oct 07, 2015 02:36pm|#3

   Steven,
   I'm afraid that "energy efficient pole building" is an oxymoron.

   If you want to make a pole building energy-efficient, you pretty much have to build an entirely new building -- either inside the pole building or outside the pole building -- to create an air barrier and provide somewhere to install the insulation. That's why people who are interested in energy efficiency don't choose dirt floors or pole construction.

   However, if you decide to let go of the idea of energy efficiency, you can certainly build a dirt-floored tiny house with a pole frame. It won't be energy-efficient, but that may not matter. If it's tiny, it will be easy to heat.

4. 
   Steven Gubkin|Oct 07, 2015 04:27pm|#4

   Martin,

   Thanks for responding. Is there a reason I couldn't use something like Larson trusses to build a space for insulation and air barrier on a pole building? I guess if this idea is really too radical, I could just go back to a standard stick built house idea, but I would really like to avoid concrete usage if possible. This is the only reason I am thinking of the pole design.

   Do you know of any examples of superinsulated houses which have been built on piles? Is this a viable option for building a well insulated house, but avoiding concrete? In this case, I guess I would be building a deck, and insulating the deck like a 5th wall.

5. GBA Editor
   Martin Holladay|Oct 07, 2015 04:39pm|#5

   Steven,
   You can certainly figure out a way to install Larsen trusses on the exterior of a pole building. The questions are:

   1. Why would you want to do that instead of just framing the walls with studs?

   2. If you go ahead with your plan, what will you attach the Larsen trusses to? Perhaps horizontal 4x4s bolted to the poles? Possible, but expensive.

   3. How are you going to air seal the gap between your dirt floor and the bottom plate of your walls?

   It makes more sense to build a conventional framed floor assembly on a pier foundation. Once you have installed your subfloor, you can then frame your walls conventionally with studs. While most modern pier foundations use concrete piers, you can use pressure-treated poles for your pier foundation if you prefer. For more information on pier foundations, see this GBA Encyclopedia article:Pier Foundations.

6. 
   Steven Gubkin|Oct 07, 2015 04:49pm|#6

   Thanks!

   It seems like building on piers is probably the best way to go. I am aware that there are metal "screw" piers, and I would be leaning towards these. I will have to get GBA prime to read the article, but I will do this shortly. This makes your first three questions somewhat moot, but I will still answer:

   1. To avoid the use of a concrete foundation.
   2. Yes, this is along the lines I was thinking.
   3. I would air seal the gap with cob.

   Thanks again!

7. GBA Editor
   Martin Holladay|Oct 07, 2015 05:02pm|#7

   Steven,
   Cob is not a sealant, I'm afraid.

8. 
   Joshua Terry|Jan 19, 2018 04:40am|#8

   I understand this is over 2 years old, but for some reason pops up on all my googling, so I feel inclined to share a link from 475 about a pole framed house. It has girts and perlins and achieved a .5 ACH. Based on the video I am unsure of the R-values on walls and ceilings, but it would be worth investigating. I speculate ~3 layers of roxul or maybe only 2 depending on post size.

   https://foursevenfive.com/475-on-site-net-zero-upstate-ny-passive-esque-house-on-a-budget/

9. GBA Editor
   Martin Holladay|Jan 19, 2018 05:05am|#9

   Joshua,
   Ben Freed and David White -- two people who are familiar to longtime GBA readers -- did an excellent job on that building. Fortunately, unlike Steven Gubkin (who posted the original question on this page), Freed and White did not want a dirt floor.