If you think the US is a capitalist country, think again. We can buy all the industrial hemp products we want, but we can’t grow the raw material to make the products ourselves. Can you say, “trade imbalance”? To learn a bit more, watch these two short videos we were involved in that discuss industrial hemp generally and then specifically as it applies to our Nauhaus prototype:

If you’re interested in volunteering for the Nauhaus Prototype Project, please contact Billy.

Click here to view the entire Nauhaus Prototype Construction Chronology.

Ian Snider and Jeff Buscher

House with forms on the South side.

Elisha measures.

Shutter being attached.

Elisha

Sarah tamps the Hemcrete.

Hemcrete in Mixer

Nauhaus Building Systems mixes Hemcrete.

Shutters line the interior South wall.

Interior of West and North walls without forms.

Electrical Box in Hemcrete

Some information about Eco-Panels, from their website:

For a truly superior building envelope Eco-Panels manufactures the only R60 panel on the market today coming in at just 8.5″ in thickness.  This panel, designed specifically for use in arctic regions, is perfect for the passive house or net zero energy designs where most modeling software calls for an R40 wall and R60 roof (of course this will vary based on region).  This roof panel will perform at better than R60 at 20deg F (-7deg C) using LTTP (long term thermal profile) and temperature vs k-factor performance data provided by the foam component manufacturer.

• 8 1/2″(21.6 cm) = R60+
• Maximum panel length is 12′-0″ (360 cm) although this can be increased to 16′-0″ for large opportunities
• Maximum panel width is 4′-0″ (120 cm)
• The insulation is high-R-value polyurethane foam injected at a density of 2.5 pounds per cubic foot.

Click here to view the entire Nauhaus Prototype Construction Chronology.

Garnet Igneous delivers supplies.

The framing is ready to receive the Eco Panels S.I.P.s.

Chris Cashman

Eco-Panels Truck

Matt, Mike and Tim

The Eco-Panels S.I.P.s are attached to a special bracket and lifted with a crane.

Jeffrey

Matt and Elijah install panels.

Matt prepares for an Eco Panel.

Matt and Elijah attach panels to the North side of the roof.

8.5" R60 Eco-Panel S.I.P. on 8" Rafter

Eco-Panels being installed on the South side of the roof

Northeast Corner

West Gable

All of the Eco-Panels are installed. Next we will add the overhangs and metal roofing.

Northwest Corner of Nauhaus Prototype

………………………..

Well, one wall anyway.

Yesterday Ian and Mario from Lime Technologies came out in the rain to help us install some Hemcrete, starting the first home in the United States to be built with the product.

The rest will be installed after the Eco Panels go up.

Click here to view the entire Nauhaus Prototype Construction Chronology.

Click here to watch the full interview with Ian Pritchett.

Click here to view the entire Nauhaus Prototype Construction Chronology.

Scored Concrete Slab

Scored Concrete Slab

Hemcrete Mix

12" Hemcrete Form

Completed Hemcrete Wall

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Advantek sheathing and brick mold are installed first to stop the foam and eventually to support the Hemcrete.

Brick Mold Installation

Home Energy Partners Spraying North Wall

Home Energy Partners Spraying North Wall

Home Energy Partners Spraying Underslab Foam Insulation

Home Energy Partners Spraying Underslab Foam Insulation

Spray Foam Insulation around Ground Loop Stub-out

Spray Foam Insulation on CMU

…all polyurethanes are petroleum derivatives obtained by combining a polyisocyanate (iso) group with a polyalcohol (polyol) group. A great chemistry write-up on polyurethane foam can be found here. While polyurethane foam can take many forms, from car seats and mattresses to spray foam insulation, the isocyanates are relatively few while the “secret sauce” of the polyol can vary wildly from manufacturer to manufacturer and product to product. To cover up its petroleum heritage some companies call these components the harmless sounding “Part A” and “Part B”, and even give the finished foam product hokey descriptions like “…having anglefood cake like consistency”, but they’re all coming from pretty much the same or very similar chemistry.

Most people know that by fermenting fruits or vegetables you can derive an alcoholic beverage (think corn->moonshine, grapes->wine, etc). This can exactly be the alcohol needed for the reaction required to make polyurethane foam! In fact, the preferred alcohol in most of the polyurethane foam industry for the past 50+ years has been acquired from post-process sugar beets – the same sugar beets used to make table sugar. This happens to be the desired alcohol because it simply gives the best overall performance of characteristics that are important to the people that use foam. Flow (in application), adhesion, strength, insulation, etc., are just a few of the characteristics looked at.

Many companies experiment with their polyol (remember this is the “secret sauce”) to chase different desirable properties, and sometimes, as in the case of soybeans, the greatest property achieved is MARKETING. I’ve spoken with many large foam manufacturers and they’ve all tried soy-based foams but admit that quite frankly it does not insulate as well, or flow as well, or adhere as well as the sugar based foams. Sugar beets are natural and organic, and so are soy beans, so why all of the hype for soy?

Eco-panels.com

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Drain and Insulation with Gravel

Finished Gravel

Vapor Barrier at CMU

All penetrations through the vapor barrier are carefully sealed.

Finished Vapor Barrier

Today the foam insulation and drain were installed at the edges of the stem walls, and the CMU was sealed.

Click here to view the entire Nauhaus Prototype Construction Chronology.

This insulation will serve as a thermal break for the concrete slab.

The CMU is sealed to lock out moisture.

These ties in the side of the CMU will serve a a mechanical connection to the spray foam insulation.