High Performance Metal Building Home
Hi All,
Long time lurker but decided to jump in and ask for some help. I’m a home builder in South Texas and it’s finally time to build my family’s dream home. Due to lumber prices I’ve decided to design the home in steel. I guess some might call it a barndominium but it will end up looking like a modern residence.
The wall/framing/insulation is what I’ve been pondering the most over the last couple of months. I’d like to share my idea and see if anyone has suggestions/concerns.
The home will basically be (2) 20’x45′ metal buildings with a square, flat roof 8’x14′ foyer separating the two. It will form a U-shape design. The (2) metal buildings I’m planning on 8″ steel columns with 8″ girts and purlins inside the columns. My thought was to either use the exterior fiberglass rolls of insulation traditionally used on steel buildings or rigid foam panels then the exterior standing-seam style metal will go on the walls and roof.
For the interior, I planned on covering all of the interior facing girts/purlins/columns with cut strips of rigid foam and glue to the surface. Then come back with 2″ of closed cell foam to cover all exposed metal. Then attach 2x4s flat on the girts/purlins 24″ O.C. Then fill the remaining cavity with blown-in cellulose.
I’m expecting this to be a somewhat cost effective approach to building a tight and energy efficient home. I’d love to hear your thoughts.
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Replies
The biggest challenge with making metal buildings energy efficient is the steel itself which is 400x more conductive than wood. You need to pay attention to thermal bridging far more with steel buildings than wood. Putting all of the insulation on the outside, or all on the inside is effective. Depending on the spacing of your framing members, any insulation in the cavities may have little value.
Hi Peter, yes that's why I planned on the fiberglass or rigid foam on exterior and covering all metal with foam.
My feeling is every dollar and more you save by choosing a pole or steel building will get eaten up with all the extra work you need to do air sealing and insulating them.
You may find this Matt Risinger video interesting.
https://www.youtube.com/watch?v=KRoMsRujUxc&t=772s&ab_channel=MattRisinger
Walta