The bales you choose may be the most important decision you make on your house. In fact, the quality of your bales can literally make or break a project. There are several things to look for in a quality bale, which I’ve outlined below. Before I get to that, let me tell you what this farmer in Oregon has available for you to build with.
Regardless of where you buy your straw, be sure to confirm that the quality is as high as possible so that you have something solid to work with. Here are the top five things to consider when buying your bales.
You want the individual stalks of straw within the bale to be a minimum of 12″ long. Longer is better. The longer the straw is at the time of baling, the more interwoven the bale will be as a whole. This makes the bale stronger and tighter.
Ideally, the bales will have a moisture content at or below 10% when tested with a moisture meter. This is not always possible as some regions have a higher ambient humidity which impacts the moisture content in the straw. I would suggest that you never use a bale that is over 18% moisture content. Further, a more realistic MC ceiling would be 15%. The bales I use, personally, run from 8% – 12%.
It’s important that the straw be tightly strung. I prefer to use bales with polypropylene twine over metal ties. However, metal ties almost always insure a tight bale. A simple test for tension is to pick up a bale by one string and then bounce it up and down. If it doesn’t deform in any way, you’re good to go. The tighter the bale, the more likely that the bales will be uniform in shape. This is an important “sub-set” of this list of five.
The bales should be a golden yellow color for most types of bales. In some cases like rice straw, the bales may appear to be slightly green. It’s important to know the difference between the kind of green you would get on a HAY bale or ALFALFA bale versus what could be expected with rice straw. It’s a very subtle green. Be sure to look for signs of water damage and/or mold growth. Any black discoloration should be inspected for moisture and mold.
Type of Grain.
This is not as crucial as you might think. If the bales meet all of the above criteria, then the type of straw won’t really matter in the end. I encourage people to look locally. If local materials can satisfy your needs, then that’s the best option. That said, if you have to look outside of your immediate area, you may find that rice bales have the best chances of meeting the all of the above criteria. Wheat and other cereal grains are often grown with genetically modified seeds which produce short crops (less waste in the farmer’s eyes). These short crops make finding long straw bales pretty hard within those grain types.
I’m always happy to post about new resources for finding quality construction bales. I have never used his straw myself, but he tells me that they meet the standards needed for construction. I asked him to confirm that they are dry (under 10% moisture content), uniformly shaped, long straw, and tight, which he did. If you’re interested in working with him, please contact:
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