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Sun, Mar 20
7:00 am

Bugs, Critters and Fire in a Straw Bale House: It seems that the main fears about building with straw bale have to do with critters eating or nesting in the straw and with fire. So, I'll talk about my experience with those, which I'm happy to say is limited.

My home is in the Sonoran Desert, near the Saguaro National Park, and this land is surprisingly full of critters. I really don't know how they all survive with so little water and with a range of temperatures from 20 degrees to 120 degrees, but they do. It's part of what I love about this area. Birds are swooping across the skies in the early morning and evening, Quail coo and call from their perches on low branches and bob in tidy lines amid the cactus. Rabbits and jack rabbits scamper away as soon as I open the front door. I've seen bobcats on occasion and coyotes very frequently. My cat knows all about the little chipmunks and mice that I rarely see - I did see some adorable prairie dogs pop up from their holes once. Of course, there are also rattlesnakes, pack rats, ground termites and all kinds of spiders, too.

None of these have nested or chewed up my straw. I owe this partially to having my bales raised about a foot off the desert floor with the stemwall. This was required because I am in sheetplain - in heavy monsoon rains, we have no large washes, so we can get sheets of water flowing across the desert. I had some friends who built nearby and did not have to raise their walls, so they put the straw up only about an inch and the day after the wall-raising, they had pack rats scurrying around the bales. I have had pack rats invade everything else - chew up the belts in my washing machine and dryer that were on the porch, take sheets off my plants when I cover them for a frost and chew up car-washing towels. They really are a pain, but they have never bothered my straw. So, I really recommend you raise your walls up on a stemwall for both water and critters.

The other reason my walls haven't been bothered by critters is that the straw is covered with thick adobe plasters. Jon told me that even if I was going to frame a wall next to the straw, as with the shower area or toolsheds, cover the straw with plaster first. Seal it up everywhere and don't allow any open areas where creatures could get to it. My only open straw area is my truth window and that has a glass pie plate over it.

Fire: These adobe (earthen) plasters also prevent fire from reaching the straw. Loose straw burns very easily; packed straw smolders unless you really torch it. I heard a story of a straw bale house that was being plumbed with copper and the plumber used his blow torch right into the straw. Well, no you can't do that. (don't put plumbing joints in your walls, either - I'll discuss that next week.) As we were stacking the straw, we had a crew stuffing loose straw into plastic bags to remove it as quickly as possible. We also did not allow smoking. A tossed cigarette plus loose straw is not a good combo. I have heard people concerned about electrical fires in the walls. I used standard Romex electric wiring, copper wires covered with thick plastic. I have had no issues. I know some people use conduit (plastic pipes) and feed the wires through those. It would make it easier to pull out the wires, if you ever had to replace them. I am no electrical expert, but if we had a short, I understand it would blow a fuse. I do have sprinklers in my house - by code. I really hope they never go off, because it would make a big mess. I fear more for my wooden porch to burn, than for this house. But do a good job on your electric - it seems most electric fires I hear about are from really old wiring, or cheap jury-rigged stuff. Pay the bucks and do it right.

Critter issues: I have had a few instances of issues that involved living creatures or bugs. One was that the birds started pecking holes in my exterior earthen plasters, particularly in the northeast corner of the house. I couldn't figure out why and I kept plugging up the holes, just to have them appear again. Finally, I coated that corner of the house with lime and the birds stopped. (see blog on Earthen and Lime plasters on Feb.12) The holes began to move farther across the wall, however, and I have decided it was because these tiny flat spiders were making webs in the textured dips in the earthen plasters. The birds were coming to eat them. Not much I could do about that, so I limed the entire house, which is what I had intended to do originally. Now, I have no issues with bird holes.

The second issue I had was with ground termites. My land is full of them - or was when I moved in. I dislike chemicals and didn't treat the area under the house before I began the floor and foundation. I also had my mind on a lot of other things, so I didn't really notice the termites. I think some of their nests were right under my floor, particularly the sunroom, because in the first couple of years after I built, I'd see termite tubes coming up through the sunroom floor. I went to a do-it-yourself pest control store and got termicide. I squirted it down all the tubes and they would go away. I did also talk to a termite professional once who told me that these desert termites don't really do much damage. They can't travel far without water and shelter, so they poke around and make tubes here and there (shelter) but don't really eat up houses. So, I didn't worry too much, but I still didn't like them poking around. I did use treated wood, per the building codes, at the base of all my wooden interior walls and yes, I highly recommend that. I think termites like wood more than straw, but not sure. At any rate, I went back to the pest control store and learned about termite barriers. There is one kind that the termites cannot sense, so they travel through it and it kills them. There is another kind that they can sense, so they leave. I got the latter and sprayed a barrier all around the exterior of my house and inside the sunroom. I poured it down the tubes whenever I saw them. That was a few years ago, and it looks like the termites have really cleared out of the area around my house. I guess they really don't like this stuff.

So, now I really don't have any issues with critters other than birds perched on the lattice and beams of my porch, so I have to wash up bird poop. For that, I put strings about an inch above the area where I don't want them to sit. The string leaves them no area to perch. I have one dove nest in the beams of my north porch, however, and I'm letting her stay there. She is very sweet and I don't mind scrubbing up the poop.

If you have other questions - send me an email -

Keep it Simple - and be kind!