We have begun to stack bales! We have had two days of install where we have gotten a small wall section up. Everything seems to be working according to plan including the lath and cutting the strings. I will now begin to detail the process up to now.
I would first like to acknowledge Dave Lanfear of Bale on Bale, who may not have been the first, but within the group NaturalBuildersNorthEast(NBNe) has been cutting strings with his pop n’ plop method for years. Cutting bale strings not only mostly elliminates a laborious step of filling holes between bales and achieving a more thermally solid bale layer without little thermal weak points, but it also forces us to devise a better system for attaching bales to frame.
The first image here is our starting point showing the rough cut 2×6 frame. To the inside is a plinth that will receive bales. Cellulose will be in the stud frame. This is a bermed north wall condition that is 4ft tall off the slab. We will show the more typical condition off the slab in the next post.
You can see the second floor joist, above, that rests on a ledger off the frame.
We avoid a typical thermal bridge with the floor system by not allowing the joists to run through to the outside wall plane and keeping 6″ of cellulose as a thermal barrier.
Where the joists run through the bale plane on the north and
south we are stopping the bales at the bottom of the joists and picking them back up again on top of the joists to avoid a lot of bale notching. In this void we will use cellulose pillows designed for joist bays from Insul-cube (http://www.insul-cube.com/photo-gallery.html). You can see that we are using Intello membrane as an air barrier bridge between the clay plaster below and above.
The membrane and the plaster will be bonded using a fleece tape from Pro-Clima designed for plaster bonding applications.
This detail will also be shown in the next post. Stay tuned.
The final image here shows a typical connection of the 1/2″x2″ lath that will be vertical on the interior and run about 16″ o.c. Baling twine is knotted on the inside and sewn through a hole in the lath through to the 2×6 exterior frame and stapled off to secure the bales. We are averaging 4 connections over an 8ft wall per lath. If you looked at a 10ft long wall and 8ft tall with lath at 16″ o.c. you would have 36 connections.
Typically, the through wall connection will be between bale courses to avoid the work of sewing through the bales. We have found that where needed, sewing extra connections through the bale after being installed is not arduous. The nice thing about this system is that you can secure the bales with the lath at various angles through the bale wall to the 2×6 frame by choosing the right stud to fasten to. We will show this situation in a future post that describes installing bales around doors and windows.