Chartreuse Blog

Day #2 of the workshop was just as busy and just as fun. We spent the first half of the day preparing for plaster with stucco mesh and welded wire mesh and the second half of the day applying the first coat of plaster on the exterior of the shed.

We had over 20 volunteers come out over the course of the first day of the workshop.

Great work everyone!

Work began at 8am by trimming nearly 70 bales with a chain saw to make them perfect blocks to build with. During bale trimming, a second group of volunteers began preparing the sills and columns for bales with gravel, waterproofing, and felt paper.

The first bale…

The structure for a straw bale shed, organized by Sioux Falls Seminary and the Sioux Falls Chapter of Architecture for Humanity, has been built at Summit House. The structure will be infilled with straw bales and plastered as a volunteer workshop Tuesday and Wednesday for the Plain Green Conference and Marketplace.

The straw bale shed, located near downtown Sioux Falls in the Pettigrew Height’s Neighborhood, will be a gateway project that may lead to creative thinking about future development in the neighborhood. Sioux Falls Seminary students serving at Summit House hope to eventually use the structure as a Tool Lending Library for the residents of the Pettigrew Heights Neighborhood for simple home maintenance and repair.

Many local contractors and building material suppliers in and around Sioux Falls are responsible for making the straw bale shed a reality. Puetz Corporation, the presenting sponsor, and the Pettigrew Heights Housing Resource Center have provided funds to make this project a hands-on workshop for Plain Green attendees, integrating sustainable building concepts with community stewardship.

Additional co sponsors have offered their time and resources. Amert Construction excavated and poured the foundation. Bruns Construction assembled the post-and-beam frame. Schoeneman’s Building Materials Center, donated lumber used in the structure, and Agan Drywall and TCC Materials have donated plastering mixes, finishes, and accessories. JELD-WEN Millwork donated doors and a window, and Carlson General Carpentry and Big Sioux Construction fi nished the roof.

Also, Koch Hazard Architects and Chartreuse Research have sponsored Joyce Coppinger, an internationally recognized straw bale expert and managing editor and publisher of The Last Straw, to oversee the shed design and workshop.

If you are interested in learning more about straw bale construction or sustainable design, join us at the Plain Green Conference. Register here.

Bruns Construction finished up the post-and-beam straw bale shed structure at Summit House yesterday afternoon.  It looks great!  Huge thanks to Bruns Construction! Also, another big thanks goes out to Schoeneman’s for donating all of the lumber.

We are now ready for the standing seam roof.  Check back for construction updates as we near the workshop.

We are almost there… the roof is taking form!

A roof bearing assembly, or box beam, sits above the box columns.  It is constructed of a double 2 x 6 for the exterior perimeter and a single 2 x 6 for the interior perimeter.  The underside of the beam will be sheathed in plywood to act as a fire stop for the wall.  The box column will also act as a nailing strip for the plaster mesh applied over the bales.  The trusses will sit above the roof bearing assembly.

The trusses are up and the fly rafters are being constructed over the drop end.

Plywood sheathing is next.

Bruns Construction continues building the structure for the straw bale shed at Summit House…

Box columns are up!

The box columns are constructed of a double 2 x 4 on the exterior and a single 2 x 4 on the interior of the column.  15/32 plywood is used to sheath the boxes on both sides.  Plywood is used, as opposed to OSB, because it will stand up to moisture better if any water were to get inside the bale wall.

The columns are as deep as the bales and sit on the base layer of sills and between the second layer of sills.  They are bolted to the sills and the foundation (two per column) with 7″ x 1/2″ anchor bolts.

The first column to go up will frame the double door.

Bruns Construction, of Sioux Falls, is donating their time this week to build the structure for the straw bale shed at Summit House, and Schoeneman’s Building Materials has donated all of the lumber.  A huge thanks goes out to our co-sponsors!

The sill plates , or toe-ups (as they are often called in straw bale construction), are used to raise the bales above grade to protect them from water damage and infiltration.  At Summit House, a double 2 x 4 was used for the interior sill and a double 2 x 6 was used for the exterior sill.  All the lumber on the project is pressure treated to prevent decay.

First, the sills are measured on the foundation.  A moisture barrier is laid above the foundation and below the sills.  A second layer is added above the inside sill and below the exterior sill to direct any moisture out of the wall.  A third layer will be added above the exterior sill to separate the bales from the wood.  The second layer of sills is notched to allow the box columns to sit between.

After marking anchor bolt locations on the plates, holes were drilled for the 7″ x 1/2″ anchor bolts at 3′ o.c.  The bolts were then hammered into the plates and foundation.

Weep holes are cut into the exterior sill plate at 2′ o.c. to allow any moisture to escape the wall.

Amert Construction, of Madison, SD, donated materials and their time to pour the foundation for the Summit House Straw Bale Shed.

The foundation is a four inch slab-on-grade with thickened edge.  Below the slab is 6″ x 6″ #10 reinforcing mesh, 6 mil vapor barrier, and 4 inches of washed gravel.  A 1.5″ ledge was formed into the foundation edge to support the exterior plaster coating that will eventually cover the straw bale walls.  1/2″ rebar is embedded in the concrete to impale the bottom two courses of bales (two per bale).

Huge thanks to Amert Construction!

Plain Green is less than two weeks away, and local contractors are preparing to begin work on the structural frame for Sioux Falls Seminary’s Summit House future Tool Lending Library.  The project is progressing as a Community Service Project built in conjunction with the sustainability conference.

The Plain Green Conference and Marketplace brings two days of advancing sustainability to the Washington Pavilion in downtown Sioux Falls April 28-29, 2010. Plain Green is the premiere conference on green design, business and ideas on the Northern Plains.  This year, the event will open with the bale raising and plastering of the straw bale shed at Summit House by Plain Green attendees.

The shed will be an example of infill construction using a modified post and beam structure.  Infill straw bale is predominately used in construction for a few reasons. First, infill is easier to meet code, get insurance, and get mortgage lenders because it is more like traditional methods of construction than structural straw bale. It is adaptable, fits into many architectural styles, is changeable after construction, and allows for a much larger structure. It is also easier to repair or replace damaged sections. The use of a post and beam structure allows for the construction of a roof before the bales are stacked. This allows the bales to be protected from the weather during construction.

The foundation will keep the bales well above grade. As long as the bales are not able to leach water from the ground, any foundation type can be used, with appropriate design considerations for material weight and climate.  At Summit House, a slab on grade with a thickened edge will be used.  Two pressure treated sill plates or a “toe-up” will be constructed around the perimeter and filled with pea gravel to provide a capillary break. A waterproof barrier will separate the toe-up from the foundation as well as the toe up from the bales.  Rebar will impale the bottom courses of bales to keep the wall in place on top of the toe up. Weep holes will be added to the exterior base plate to allow drainage.  Two foot overhangs will also protect the bales from moisture.

The shed will be stuccoed with a cement-lime plaster.  Plasters are made up of a binding agent, the main component of the plaster, a structural filler such as sand, rock or aggregates, and water.  At least three layers are applied, a scratch coat, a brown coat, and a finish coat. When using cement and lime plasters a metal mesh is used as reinforcement in the plaster.  A moisture barrier will not be used.

The project is presented by Puetz Corporation.  Co-Sponsors include Bruns Construction, Amert Construction, Koch Hazard Architects, Jeld-Wen, Schoeneman’s, Carlson General Carpentry, and the Pettigrew Heights Housing Resource Center.