CDAE 170 Solar Building StrategiesClass #7 Oct. 18, 2003

Gary FlomenhoftBSME, MAPP, CEEResearch AssociateGund Institute, SNR

Review of Glazing-Chiras

Window glazing:

South glass: 7-12% of floor footage

North glass: <=4%

East glass: <=4%

West glass: <=2%

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

Sunspace

Skylight

OVERHANG

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

SHADING

Vapor Barrier

INSULATION VALUES

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 40orDIRECT or INDIRECT WALL MASS* in solar room: glazing >7% x 8.3

*Not everyone agrees

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

ENERGY COSTS