I have wanted to do a "real" update on the house for a while, with information to help anyone thinking of using the dry stack building method. But with the actual work of building, getting gardens in, a booth at the Farmer's Market and trying to run a small business, there hasn't been anytime. There is already a lot of written information on this subject though and I'll share that, along with our personal experience with you.
Here are some things we ran into while building with concrete block. Concrete may not seem like a "green" building choice, but it will withstand extreme weather and the weight of building up around it with earth, or earth-berming. It also has a great deal of mass, which will greatly reduce the heating and cooling effort. Therefore less spewing pollution into the atmosphere and less work bringing in wood in our old age. Thermal mass in a house in the form of walls or floor will pull the heat out of the room in the summer and in the winter will store heat and give off slowly overnight night.
We originally were going to use the dry stack concrete block building method. Actually, really early on we were going to do slip form concrete method that Tom Elpel teaches. But the dry stack method was supposed to be easier and perfect for the novice.
After reading more about slip form, we also thought the rebar requirements would be too labor intensive, block seemed easier. But after working with rebar, we found that bending the longer pieces isn't hard at all w/out a bending tool. I would like to build something with the slip form method now to compare.
Rob Roy's book "Earth-Sheltered Houses" is a good overview and detail of house building and one of the methods highlighted is the dry stack method. Like any one book though, you can't build a house after reading it alone. It was about the best book for starting out for us and from there we got more detailed books on plumbing, framing and roofing, plaster, solar power etc. His book is tattered and pages are falling out of the binding we've referred to it so much.
The USDA has a brochure on the dry stack method which is brief step by step.
There are videos and a rather poorly put together book at this site on dry stack method. We purchased all his materials and learned a few good tricks. He has created a better chart for block length and height than provided by the USDA, because he accommodates and teaches about wall growth. If you locate blocks that are square and uniform in size and want to build with this method, I begrudgingly suggest you purchase this over priced material. I think the price is ridiculously high for the book because it's so poorly written, more expensive than professionally written bound books and can't be sold used since it's in electric format only. I will admit he did have a few good tips in there that I didn't find anywhere else. If we were going to use this method for our house (we are currently building my mother-in-law's house), I wanted to try writing a better book and shoot a longer video that would take you from underground to roof. If you've never done it before, you will not be able to build a house watching his videos or reading his book alone.
We were not impressed with the dry stack method however and dropped it. For us, it was much easier just to mortar blocks. I've since spoken with several people who have the same opinion, they tried it, but it's more trouble than it's worth if you can't find uniform blocks. However, the dry stack wall is supposed to be much stronger when surface bonding cement is applied than a standard mortared wall.
To start building with this method, you have to clean and sort each block by size. This entails either dragging them back and forth across the blocks below them on the pallet or using a broken piece of concrete block and knocking off the high spots, or as in the video mentioned above - using power tools. If you don't, of course the blocks won't lay level because you don't have mortar. The cleaning wasn't that hard, but took time.
Then we had to sort by size since you can only dry stack a similar size per row. Otherwise you'll end up with a space in that row that will drop the block in the above course down creating a chain reaction of un-levelness. There were 4 average block sizes in our total order. It is not easy to sort by size since the blocks are a different height depending on what part of block you are measuring. We measured blocks at the only two locations available for purchase in our area and the blocks were just as bad at both locations. The blocks we purchased were not remotely square, straight or the same height from one end of the block to the next. This was our biggest problem.
Metal shims do not easily bring your block to level as reported. Using sand to level was even worse as there was always that one big piece of "sand" to throw off level and you have to literally pick sand particles up, put the block down - nope still not level - repeat over and over. After trying two rows of the dry stack method, which took an excruciatingly long time, mortar seemed almost magical in it's ease and speed. After one row of mortaring, I got the hang of it and we started going much faster with laying block.
We watched mortaring videos on youtube over and over. This is one of the best videos I found. The first time through is too fast, but I would watch it after I mortared and picked up a nuance each time.
In addition to the difficulty of trying to get blocks level using the dry stack method, we ran into problems with the line levels themselves. After we kept running into problems with our elevation from one day to the next, we tested the levels. Two of the line levels were not accurate and two were. We also tried using a water level and that was not accurate enough either. We bought a transit that wouldn't "zoom" in far enough so that you could not even see to the other side of a small house and then borrowed a transit that would move up or down, changing the measurement greatly, when bringing it into focus (yes even with the screws being tight). So equipment tripped us up for a while till we discovered they were faulty and bought or borrowed tools that worked.
After laying block up to the 7th course, we hired some help that had scaffolding and with all those hands we finished. They were kind enough to leave the scaffolding behind so we can apply the surface bonding. Since some of the courses are dry stacked and some are not, we decided to go ahead and apply surface bonding to the walls. This will ensure their strength against the weight of the dirt that will back-fill the house to make it earth-bermed. With so many hands helping though, we forgot to put in a transom I wanted for the bathroom - oh well.
Here is a progression:
Jeffrey has just finished framing the south wall using a combination of old timbers we picked up at auction and new material. Some of the windows will be those we also picked up at auction.
Right now we are cleaning a big straight log we found down in the woods. It will be used as a vertical support post and will be beautiful between the kitchen and living room. Our neighbor is a woodworker and let us borrow his draw knife to clean off the sap wood. We are getting close to the heart wood and it's such a beautiful redish color. We are learning a lot about wood from him. He came over tonight and helped just about finish it. So this beauty is about ready to place.
We are trying to figure out what sort of horizontal support beam to use right now and are going back and forth. We are also debating on what to do about the floor. Originally we were going to do an earthen floor. A good bit of dirt for the floor has already been screened. However, my mother in law is paying rent and utilities and it can take several months to lay an earthen floor. I love earthen floors and will definitely have one in our house, but the money hemorrhage has to stop. Since we are so over due on building this house for her, we need to make a tough decision about the floor.
The interior walls will provide a good bit of mass and it's a small house. So I hope we aren't going to loose too much by not putting in an earthen floor. We are currently trying to find quicker methods of installing an earthen floor, but we may end up just putting in a traditional floor, perhaps using tile for a wee bit of mass.
In other news, the tomatoes, peppers and herbs look GREAT! The sunflowers are gigantic as are the jerusalem artichoke. Brassicas, potatoes and beans are fair to midland. Fruit trees and young elder trees took a beating from the 13 year cicadas, but my friend found a mature blooming elderberry on the bottom land. The wild oregano is in bloom everywhere and I've been trying to harvest a hand full of leaves when I pass the patch. We cleared a new path to a beautiful area of the creek with a natural water bowl and beach, and that will help make it easier to water the garden this summer. We've have learned to cook with arugula, I just planted it because it was supposed to be good for the carrots. The carrots didn't come up, but the arugula went crazy - and we are crazy about it. I am successfully growing gladiolus, my favorite flower, for the first time.
We've been learning all we can about perma-culture and setting up our systems. This is a good forum for that. I've been planting comfrey for chop and drop and left the area around the garden surrounded by queen anne's lace and all sorts of other wild flowers, clover, roses, butterfly weed etc. I"m learning about planting guilds and building up the soil. Trying to learn the difference between organic farming and permaculture. I think we are probably several years from a good permaculture influenced system, but we are going that direction.
Here is a video ideo with Helen Atthowe that I thought was nice. According to Paul Wheaton of permies.com, she is right up there on the permaculture pedestal with Sepp Holzer and Masanobu Fukuoka.
On a personal note... I am trying to get an herbal website going. I am stuck on the paypal shopping cart thing. If anyone would like to help me, I can trade herbal preparations or can teach about making them.