Wofati eco building

Wofati is a type of natural earth-sheltered building developed by Mike Oehler and expanded upon by Paul Wheaton. Wheaton coined the acronym, which means Woodland Oehler Freaky-cheap Annualized Thermal Inertia. "Woodland" because it is the optimal location for such a building; "Oehler" after the pioneer, "Freaky-cheap," due to the Fairly-cost effective or frugal materials; and Annualized Thermal Inertia from a book by John Hait called "Passive Annual Heat Storage" which inspired much of the reasoning behind the Wofati design.

Imagine living in something that looks like a log cabin from the inside, but:

• it has more light
• it doesn't need heat or A/C
• it is three times faster to build
• it costs about five times less

The design is basically a pole structure with a green roof. The structural design accommodates water flow from rainfall, as well as leveraging the use to soil for insulation and the orientation of the land to take advantage of sunlight.

Wofati Definition

1. Every drop of rain has a complete downhill soil path and never encounters a roof edge.
2. There are two layers of membrane. The lower layer, which hugs the structure, and the upper layer, which defines the thermal mass that surrounds the structure.
3. The uphill side has an open trench to move water around the structure.
4. The uphill side has a roof that extends at least five feet beyond the exterior wall.
5. There is at least eight inches of dirt between the two layers of membrane. There is at least sixteen inches of dirt on the top layer of membrane.
6. The inner pole structure is made of logs.
7. No treated wood is used in any of the structure.

Wofati house definition

1. has all of the properties of "wofati definition"
2. At least 35% of the uphill wall is glass or some other material that allows light to pass through
3. The house is not air tight
4. There is a large gable roof to the downhill side with 35% or more glass or some other material that allows light to pass through
5. The house is NOT "underground". This is an above ground pole structure with an earthen roof.

Wofati cooler definition

1. has all of the properties of "wofati definition"
2. includes venting tubes - much like what is used for a root cellar

Wofati freezer definition

1. has all of the properties of "wofati definition"
2. Includes a pluggable vent tube that runs through the core of the thermal mass. The idea is to open these tubes on days that are below 10 degrees.
3. The upper layer of membrane must cover at least five times as much square footage as the available square footage in the structure.

Wofati animal shelter definition

1. has all of the properties of "wofati definition"
2. Must be big enough to drive a tractor inside

See also[edit | edit source]

• Construction techniques
• Compressed earth brick press
• CCAT's living roof
• Earthships

External links[edit | edit source]

• wofati eco building - richsoil.com article with explanation and instructions, including pictures and video.
• Better World Book - Wofati Podcast Part 1at Permies.com
• wofati eco building (forum thread) - permies.com forum thread for questions and ideas on the subject.
• Wofati greenhouse Q&Aat Paul Wheaton's You Tube
• Allerton Abbey tour - the first wofat!at Paul Wheaton's You Tube