CDAE 170 Solar Building StrategiesClass #8 Oct. 25, 2004

Gary FlomenhoftBSME, MAPP, CEEResearch AssociateGund Institute, SNR

Review of Insulation-Chiras

(Olson and Schwartz)

Climate Wall ceiling

Temperate R-30 R-60

Cold R-40 R-80

kachadorian R-32 R-40

Hot R-40 R-80

Review of Glazing-Chiras

Window glazing:

South glass: 7-12% of floor footage

North glass: <=4%

East glass: <=4%

West glass: <=2%

Review of Glazing-Chiras

Review of Glazing-window insulation

OVERHANG p.107 (www.susdesign.com/overhang)

L = Length of Projection

H = Height of window opening

L = H / F 44º latitude: F=2.0-2.7

Review of Direct Gain Thermal Mass-Chiras

Sun-tempered = 7% of floor footage. Incidental mass takes care of it (sheetrock, framing, furniture)

>7% glazing needs extra mass.

MASS THICKNESS 4-6”

DIRECT FLOOR MASS: Each square foot of glazing over 7% x 5.5 orINDIRECT FLOOR MASS: glazing >7%sq.ft. x 40orINDIRECT WALL MASS: glazing >7% x 8.3

Direct Gain Principles-Kachadorian

1. East, South and West glass should be 10-20% of total exterior heated wall area

2. Peak supplied February day increase in solar slab temperature should be 8 degrees.

Review of Indirect Gain Thermal Mass-Chiras

(Thermal storage or Trombe wall)

Vented Trombe wall

Review of Indirect Gain Thermal Mass-Chiras

(Thermal storage or Trombe wall)

MATL DENSITY THICKNESS

CONCRETE 140 8-24

CONCRETE BLOCKS

130 7-8

CLAY BRICKS

120 7-16

LT WEIGHT CONCRETE MASONRY

110 6-12

ADOBE 100 6-12

Review of Indirect Gain Principles-Chiras

1. Orient south +-10 degrees

2. High performance glass

3. Thermally isolate glass

4. High quality caulk

5. Use Selective surface or high temp paint

6. Use dense material

7. Minimal interior finish

8. Insulate glass at night

Direct + Indirect glazing = MAX 20% of floor area

Selective Surfaces

Selective Surfaces

Sunspace