Can this plant lower indoor humidity levels?

April and I have been doing research about how to lower the indoor humidity levels in the house. Recently, the outdoor temperatures skyrocketed to the mid-80s after several weeks of 60 degree temperatures, so everything is really humid and damp… Including the house.

So humid, in fact, that mold started to develop all over the earthen floor, especially around the rugs. We took all the rugs out and I mopped the floor with water, but that was a bad choice… since it didn’t dry easily. A couple days ago, we wiped the floor with vinegar to help kill the mold, and set up a box fan to blow air over the floor (thanks to our neighbors for lending us electricity!) to help it really dry out.

We borrowed a digital thermometer and humidity reader thingy, and it read humidity levels of around 80% inside the house! Hopefully it wasn’t totally accurate… But nevertheless, it’s clear we need to rectify this humidity situation. We definitely don’t want a moldy living environment.

Since we don’t have electricity to run a dehumidifier, April has been researching ways to decrease indoor humidity levels through other means. There’s big silica gel bags that you can hang up to soak up moisture from the air, and then heat up/bake later to dry them out to reuse… But who wants big bags of weird silica gel hanging in their house? We might have to do it if the humidity stays constant, but I thought this was the most interesting possibility….

Air plants – can they reduce indoor humidity?

Air plants! Huh? Plants of the genus tillandsia grow in tropical regions and thrive without soil or root systems – they gather moisture and nutrients from the air itself.

All moisture and nutrients required by the plant is absorbed directly through the leaves by means of the tiny silver scales which cover the plant. The thin walls of these scales permit water to enter the leaves, but prevent its escape. The silvery colour of the scales also helps the plant remain cool by reflecting a portion of the sunlight that reaches the plant…. As you might expect, a plant that is able to cling to the top of a tree, and supply its needs from rain and dust is quite easy to take care of. If they are placed where they will receive bright filtered sunlight and normal room temperatures tillandsias demand very little else. Their need for water can be supplied by either frequent misting, or for those who cannot remember to mist a plant every few days, the entire plant can simply be immersed in room-temperature water for about half an hour every week to ten days. This will permit the plant to absorb all the moisture it will require for the next week or so.

Check out more about tillandsia here. Presumably, if you place the air plant in a humid or moist environment, such as in a bathroom or near a kitchen sink, you don’t even have to worry about misting the plant. Is is then safe to assume that if your whole house is humid that the plant will thrive by capturing some of that moisture from the air, and in effect, lowering your home’s humidity levels? Maybe… but we are so intrigued by the possibility that we just purchased a dozen tillandsia.

Hopefully these plants will help to keep the house drier. If not, it’s still an interesting experiment…

Do you have any ideas about how to passively lower indoor humidity levels? If so, let me know!

Image credit: HK James Ho

The night I returned, I went to check out the interior of my house with a flashlight. The outside temperature was something like 1°F or less, and lower with the wind chill. Almost the entire interior of the house was glistening with an icy sheen – the walls, and ceiling all had a light coat of ice. It actually looked quite beautiful but it made me a little concerned. I’m not sure if it’s the result of moisture that is still locked in the house, or from condensation, or what. There is some light mold in some spots, too.

Should I be worried? I’m not sure. Is it enough moisture to cause a problem? I wish I knew. If anyone has had a similar experience, I’d love to hear more.

Cobbing complete!

With Karen’s and my dad’s help, I completed cobbing. The walls are finally done! In just a few days, the gap between the walls and the roof was closed. It was very satisfying to see the final line of the wall meet the decking of the roof. It was awkward work having to stuff the small spaces, but it wasn’t too bad…

Windows and door installation

Next came the windows and the door. My dad and I struggled with installing the first of three windows, continuing our typically discombobulated history of collaborating on work projects. After a couple of hours, we got it in, and the next two were much easier. The north and west windows are casement style, and the southeast is double hung. All are doubled paned.

The door was surprisingly easy to install. A few shims here and there and it was set. Unfortunately, however, it’s not quite what I expected. Meaning that I must have looked at the door wrong when I first found it, and it doesn’t actually open the way I expected it would. It opens outwards instead of inwards. For now, I’m not locking it in cob, just in case I decide to change the door later (or even make my own door). It keeps the cold out, which is good enough for now.

I used sheep’s wool to insulate around the window and door frames where there are air gaps. The wool was free from a local farm, and I simply carded it using my hands before stuffing it in the gaps. The house is now sealed!

Losing my EPDM membrane…. almost

Beyond all that… the biggest happening of the week was almost losing my EPDM membrane on a very windy day this most recent weekend. What a nightmare. All day Sunday, there were gusts of wind up to 45 mph. Since the pond liner was not tied down or weighted in any significant way, it was flapping pretty heavily throughout the day. At one point, my dad ran to find me and said “your roof is about to blow away”, and we made it out there just after the ropes around the tractor tire flew off, essentially freeing the membrane from the roof completely.

We held onto the corners for dear life, and then Jeff ran to find help. Soon a pack of ten or more people were running towards the house, and each grabbed a corner of the membrane, some getting smacked in the face by the EPDM in the wicked wind. Tony and I scaled the house carrying rope, and working like spiders, we all wove a giant web over the membrane. It was a pretty intense experience. People were being lifted off the ground as they held onto the membrane, and up on the roof it was no better. Every time there was a giant gust, the membrane lifted us up off the surface, and there was little to hold onto. Frightening.

Eventually we got the whole roof tied down. Unfortunately, I think the membrane suffered a bit in the process, and there is some damage and wear. Hopefully the parts that are damaged are close enough to the edge that will get trimmed. I also lost some cardboard cushioning that will have to be replaced, so it’s going to take a fair amount of work to get that material back under the EPDM and prepare for the next step in constructing the roof.

Scratch plastering

In the meantime, I’ve been doing some scratch plaster inside the house with the help of my new (and probably last) work exchanger, Kyle. We smoothed out the nooks and shelves, and some of the rougher parts of the wall that experienced some rain damage. It’s amazing how much more pleasing/smooth it looks now, even before the final coat of plaster is on.

Prepping for the earthen floor

Today, Kyle and I cleaned out the house and raked up loose cob and some grass to prepare for moving gravel inside. I decided to leave the topsoil in my building. I didn’t level it either, figuring that if any moisture did get in there, it would drain more easily with the natural slope. The soil has been well tamped by now, after walking on the ground all season, and mixing cob in there as well.

We moved gravel in by wheelbarrow. Because of the slope of the site, the gravel will be 4″ deep on the east, and up to 12″ deep on the west. Above this gravel will be 5″ total inches of earthen floor mix (divided between two layers).

I expect we’ll finish the gravel moving tomorrow, just in time for our traveling Halloween party. I plan on having a gravel-tamping dance party during at my stop. Many feet make work light!

Pictures coming soon!

Yesterday afternoon and this morning, I put some final touches on the cob walls, leveling them in preparation for the soon-coming reciprocal roof. After I smoothed out some of the last cobs, I took a minute as I stood on the lean-to trestle, just staring down at the walls which now easily tower over my head, and I wondered in amazement.

It has been quite a journey to this point, moving over 40 tons of material. That’s a lot of earth. More specifically, it’s been 194.5 batches of cob so far. All this over 57 days (which were not all full work days, mind you.)

And it’s not over yet, but this massive portion of the process is, at least. Here are some photos of the structure.

Interior, looking southwest.The bed will be positioned along the far wall, under the window. The joists will support a 7.5′ wide, 22″ deep storage shelf.

The north wall interior, with nooks and a shelf at the foot of the (future) bed. The rocket stove will be to the left of the window. Exterior backside, looking southwest.

Entryway with storage nooks. A gigantic corner bookshelf.

Happy.

Here’s a couple of photos of the 99% complete cob walls. I figure I’ll be able to finish them off tomorrow, perhaps Sunday if it takes a couple more batches than I expect. Reciprocal roof: here we come!

Also, in the top photo you might notice a post near the entryway. This black locust post will bear one of the reciprocal roof rafters, making for a nice little overhang near the entryway. Call it a really small porch, maybe, but this should provide some decent extra coverage from the elements.

With the help of my superstar work exchangers Dan and Danielle, the cob walls are nearly complete. Unfortunately, D&D departed today to begin their own pursuits, but I am hopeful that I’ll be able to complete cobbing by myself by the weekend. I suspect it will take 10 or so batches to level out the walls in preparation for the reciprocal roof – no problem! (My estimations are historically inaccurate, but I feel pretty confident about this one.)

It’s amazing how tall the west wall (see above) is/feels, compared to the rest of the house. A little bit of slope can go a long way.

Last night we had a third campfire in the house, and several folks have suggested leaving the house as is, without roof, because of the dramatic light cast by the fire on the walls. It’s quite a sight. Maybe I’ll have to design a retractable roof…

Recent highlights the past week included cobbing above the south window, removing the door brace (ahhh for easy entering and exiting!), and sticking in most of the deadmen for the roof rafters. It feels more and more like an actual house with each passing day.

This weekend, I had a strong urge to do some cobbing after dinner, during the sunset hours. So, last night we (myself and Dan and Danielle [my two work exchangers], later joined by Liat) ate dinner and stomped a batch of cob as the sun went down. By the time we were done stomping, it was super dark and pretty dang difficult to actually get the cob on the walls, but we managed.

After that first batch of cob, we figured it would be a good idea to make a campfire inside of the house. Ted and I set one up, and the house glowed like a giant woodstove. It looked great from the road, with a bright orange aura.

There was a full moon that cast a great light on the walls as it rose towards the sky later that night.

Fun stuff.

With help from my most enjoyable new work exchangers Dan and Danielle, I am inching closer and closer to the roof of my cob house. Today marked the completion of one of the few remaining and more challenging elements before that happens, though — installing joists for a wide shelf positioned above the (future) cob bed.

Yesterday, we built a joist rig with some 2×4s that could be buried in the cob: three 38″ long joists attached to one long 2×4 banged out with lots of nails. This whole thing was placed on the cob wall and leveled, joists braced, and then cobbed in place. Hopefully the joists will be strong, as they are buired in all 16″ of the cob wall. The shelf will be 22″ wide and 7.5′ long and will mostly be for storage.

Time will tell whether or not the joists are buried in enough wall to support the weight of potential clutter on the shelf. I am hopeful!

The past week has been extremely productive, thanks to some help from Apple and a few other folks from Sandhill Farm. The cob walls are nearing 85% complete, I’d say. But before I finish them, there are other things to take care of, too. Namely, I need to install lintels above my windows and doorway, and start preparing for the roof.

Lintels are lengths of material (usually, slab wood, pole wood, milled lumber, bamboo, etc.) used to span window frames in natural buildings. They help to bear and spread the weight of the material (cob, in my case) above windows and doorways. Depending on the material, they can be pretty decorative, too.

I cut some osage orange wood for my smaller window lintels, leaving the bark intact for a more ‘raw’ look. I’m pretty happy with the effect.

For my large south-facing window (see top photo), I chose to use some pole wood that I got from Skyhouse. I wanted something straight and easy to work with, but also round, so these fit the bill. These lintels are shorter than is ideal (they only overhang the window by six inches on both sides), but hopefully they will still get the job done.

I am just now starting to think about how the rafters of my reciprocal roof will be placed on the walls, so these next few days will be heavier on the “thinking work” side of things…