Compressed Earth Block Wall Systems-B4 17 · Compressed Earth Block Wall Systems Presented By Dan...
Transcript of Compressed Earth Block Wall Systems-B4 17 · Compressed Earth Block Wall Systems Presented By Dan...
1
Compressed Earth Block Wall Systems
Presented By
Dan JohnsonDavid Romary
Driftless HomeWrightswww.driftlesshomewrights.com
One Element of Green Design
Earth Blocks
2
Workshop Goals
1. Introduce Earth Block Construction.
2. Increase Understanding Of Building Material Thermal Properties. (especially masonry)
Adobe Earth Block BrickSun Dried Hydraulically Pressed Fired
Approximately Half the World’s Population lives in Earthen Structures
3
Taos Pueblo
Longest continually occupied structure in North America.
Beginning1000 to 1450 AD
4
5
21st Century
Cinva Ram/Hand Press
CEB Block Press
6
Soils For CEBs
Range of Proportions
Gravel: 0-40%
Sand: 25-80%
Silts: 10-25%
Clay: 8-30%
(Source: CRATerre-EAG)
Stabilized Blocks vs. Unstabilized
Block Testing in Iowa
Stabilizers
Portland Cement
Lime
10% Soil Moisture is the Ideal for Stabilized Block Making
7
Approx. CEB Compressive Strength(Based on MEB experience)
Stabilized 700-1400Unstabilized 500-1000Code 300
Why build with Earth Blocks in the Midwest?
•Sustainable Building Material•Thermal Mass•Architectural Freedom
8
Sustainability
Sustainable Resource
Embodied Energy= the quantity of energy required to manufacture and supply to the point of use, a product, material, or service.
9
Cement-making = 5% of Greenhouse Gases
Wall building “resource” taken from on site.
10
Thermal Mass
Conductive Heat Loss
R-Value: Measure of thermal resistance.
U-Value: Measure of heat transfer.
R-value is inversely proportional to the U-value
R=1/U and U=1/R
11
Thermal Mass
The capacity of a material to store thermal (heat) energy for an extended time.)
Passive SolarDesign
Thermal Mass is essential for heat storage and to prevent overheating
12
Thermal Performance
Earth Block Steady State R-value does not reflect the thermal performance of a CEB wall.
Wall design determines a CEB wall’s performance.
Greenhouses
13
Masonry Heaters
14
ArchitecturalFreedom
Foundations
Footings•10” thick•33% larger the stem wall
Stem Wall•Centered on Footing•Can be 2” less then CEB wall width.
15
Foundation Options
•Footer and Stem Wall
•Rubble Trench
•Frost Protected Slab onGrade
Mortar Options
Dry Stack
Slurry
Mortar
Wall showing slurry method.
Slurry•Same soil as block.
•Screened to 1/8”
•Mixed like a bad
milk shake
16
Dry StackSays it all
Important to avoid point loads by keeping courses level and free of gravel, dirt chunks, twigs, etc.
Mortar
Lime Based Clay BasedPortland Cement Based
Dan’s Lime Mortar1 part Lime Putty
2.5-3 parts Sharp Sand
Clay Mortar
1part clay dirt
1-2 parts Sharp Sand
17
Bucks and Bond Beam
Lintels(See Code For Sizes and Length)
CEB Construction Considerations for the Midwest
1. Moisture2. Thermal Performance (Thermal Mass)
18
Moisture Considerations
Block Testing in Iowa
Roof Overhangs and Gutters
Air Sealing Wall Penetrations
Wall penetrations are the number one source ofmoisture movement into the cavity of a wall.
19
We want to limit the amount of moisture entering the wall, while still maintaining a breathable wall.
LikeSkin
Base Coat: Lime Plaster and Exposed Block
Earth Block Inc./Jim Hallock
Exterior Finish
-Plaster/RenderLime Based
-SidingReclaimed WoodLocal WoodCement Fiber
Double Wall System
Advantages
1. Several Insulating Options
2. Chase for Electric
20
Insulating Options
Insulation R-value-Perlite 2.7-Vermiculite 2.7-Rock Wool 4-Icynene 3.6--Dense PackedCellulose 3.5
-Sawdust &Lime 3.0?
Interior Veneer CEB System
21
Thermal Mass plus Insulation
Excellent! Wall System
“ . . . thermal mass and insulation are natural allies. The better a building is insulated, the higher are the chances for energy savings (thermal mass will be much more energy efficient than lightweight building envelope technologies).”
ORNL- Buildings and Technology Center
22
Massive Cavity/Double Wall SystemMinneapolis, MN Climate
Steady State R-value of 19
Dynamic R-value of 30.07
Source:Oak Ridge National Laboratories
Double WallwithElectric and Phone Wiring
23
CEB Radiant Veneer WallDrywall Alternative
Lime Plastered Veneer Wall with Radiant Tubes
24
CEB Floor
25
Pella, IA 2005