I have a straw bale home inspection tomorrow. I’ve looked at several NACHI archive articles, Wikipedia, and a NACHI youtube video. I’m out of my realm of expertise on the structural and construction side of this wall system, although I’m prepared as best as I can be. Any experts here?? Seems these are important issues: Plaster cracks, moisture, proper window placement and flashing, roof overhang, foundation height… I expect indoor air quality may be an issue if the house is tight.
Is the wall weight excessive? This is a per foundation set on bedrock. Concerned about pier size and spacing. We usually have plenty of snow load; northern MN.
I’d put a disclaimer/description in the report mentioning it’s an uncommon construction method and that future repairs/modifications will likely be more complicated and expensive than on a typical house. Otherwise, I’d just inspect to see if it’s performing as intended and not see my role being to overly scrutinize and redesign the house.
One of my neighbors has a straw bale home. His home is stucco over the straw. I’ve only inspected a few of these over the years. Water intrusion along the bottom is something my neighbor and some of my inspections have had.
Cool!
Just went to an “embedded carbon” talk by the head of https://www.strawbuilding.org/ . There’s even a straw bale building code now.
For your inspection remember performing not conforming. You won’t be able to determine if the construction is “right” but you can look for signs of stress. Cracks, stains, coverups.
As with most construction forms, water in the wrong place is the issue of fundamental and extensive concern. Having seem plenty of rats in fiberglass, I can’t say if rats in straw bale walls are worse. But certainly not good.
Keep in mind likely the roof is self supporting, and structurally separate from the bales.
Look for a “Truth Window”
(Though of course that word, Truth, is now loaded and disputed)
That means cracks in the stucco right? Does he know where the mice are getting in? Like any building rodents it’s all about blocking entrances and exits, no?
Never inspected one… from what I am reading, seems like the key points are to: 1) make sure the bales are fully sealed against moisture and pests. So, any hole in a wall exposing the bale is something important to report. 2) make sure that the bales are covered / sealed with something non-flammable - presuming drywall is suitable. And lastly, 3) look for any signs of settling (cracks, deflections), which could mean that there is decay of the straw which could be a structural concern.
Thanks for all the replies. I did spend some research time pre-inspection. There were no stress cracks in the plaster, the seller claims no mice ever inside the home. The seller/owner/builder, a MN licensed contractor, was able to answer some of my structural and other questions. Fortunately the builder was very knowledgeable and qualified. Good building!
