Sunlight will break down polypropylene bags after a few weeks. Here’s a new idea to protect against UV damage. Tarps are big and awkward. Painting the bags is extra work and sort of messy. Shade cloth seems like one of the fastest, best methods to protect against UV damage. Secure the shade cloth to the bags with 2” galvanized roofing nails or something similar. Thanks to Ruedi for this tip.
Ruedi: “I’ve decided to attach shade cloth to the wall to get a better, permanent UV protection during building.”
The shade cloth is a great thing, but 90% is a must. I had some bags stored under 60% shadenetting, and it degraded inside of 5 months.
The issue with plastic tarp (for me anyway) is that on a daily basis, puffadder and cobra will turn it into the next episode of MTV cribs. So I learned to loathe lifting the tarps up daily. The upside of tarps is rain protection (but we don’t see that often).
TLDR: 90% shadecloth, and when you’re done – use it on the gardens.
I thought on this and wondered if just covering the bags with a runny slurry of cement. The consistency of paint would be the answer. I also think once you start building, how long are you going to take? If it’s going to be a long time, it seems like a bad idea. Maybe waiting until you are really ready to bang it out is a good idea. Also, how long is to long? Until the bags start to go bad.
Best to get ‘er done in my opinion. But you never know what life has in store for you. There are often many unexpected delays and homes usually take far longer than expected. If the bags fail, you can burn off the bags and still plaster without problem. But of course it’s best to protect the walls so you don’t have to remove the bags. Buy UV protected bags if the project will take a long time.
Thanks Owen
Since I don’t frequent nurseries I didn’t make the connection. That does seem like a better option money wise. The tube must be a different material than a common tube. Correct?
They’re regular pp tubes. Same material as all earthbag houses. It looks like he wrapped the shade cloth around the tubes so the inside is also protected.
Can you tell me what shade cloth and this woven pp tube is? I’d love an alternative to tarps because my project will need a considerable amount. Costly. I have always assumed this would be part of the cost of the build. I’d love to a cheaper way. By the way, where’s our fellow commenter Jay? He has good advice at times.
Look up local suppliers of shade cloth to reduce shipping. Shade cloth is used by nurseries to protect vulnerable plants from intense sunlight. It’s very common, cheaper by the roll.
Woven polypropylene tube is the same material as sand bags only in tubes. That’s what’s used on 99% of earthbag houses.
I’ll third that. Tarps are awkward and break down. I used some 90% cloth that I rescued on some bagwork that i laid around my berm out back to keep the dogs from climbing up to a ferrocement porch and jumping over the fence. It’s been there a while, looks decent, bags are still I’m good condition, and will remain until I collect enough “flagstone” rock from the hills to mortar up the whole back side. When I do that, it’ll most likely be reused to replace expensive lath in some ferrocement project.
You’re covering your walls with flagstone? Please send a photo if you have one.
We also used shade cloth on the round house at NL. Just pinned it with bamboo sticks.
When the earth in the bags was dry, we ended up cutting the bags completely off, as our earth render bonded fast to the exposed and hardened earth that had been contained in the polypropylene.
Reudi way want to consider this.
We look forward to your report.
Another way to get UV protection is to use 2000hr UVI rated woven pp tube. I have both 14″ & 18″ wide rolls in stock now ready to ship.
Steve 949-338-5978
That’s great when UV resistant bags and tubes are available. That’s not always the case, unfortunately.