Energy Efficient Walls - PowerPoint Presentation

Presentation on theme: "Energy Efficient Walls"— Presentation transcript

Slide1

Energy Efficient Walls

Kelly Kissock, Ph.D., P.E.Department of Mechanical and Aerospace EngineeringUniversity of Dayton Industrial Assessment CenterSlide2

Minimize Surface Area

ACT2 HouseSlide3

Effect of Framing Bridges on Interior Wall TemperaturesSlide4

2x4 and 2x6 Frame WallsSlide5

Truss and Beam with Wet-Blown Cellulose

1996 ASHRAE Technology AwardSlide6

Structural Insulated Panels (SIPs)Slide7

SIP Thermal Resistances

Whole-wall effective R (hr-ft

2

-F/Btu) for 4.5-in SIP and frame wallsSlide8

Strawbale Houses

Low embodied energySlide9

Strawbale HouseSlide10

Steel Framing

Steel conducts heat over 300 times faster than woodEmbodied Energy (2,000-square-foot house, EBN):Steel: 53 mmBtuWood: 42 mmBtuUse phase 48-92 mmBtu/yr (EPA)

Thermal resistance (JTM):

Rwood is 22% greater than RsteelSlide11

ASHRAE Correction Factors for Metal Framing

Example

Correction Factor for wood framing ~

0.90Slide12

Insulated / Uninsulated Walls

Tint,ins = 74 F

Tint,unins = 64 FSlide13

Insulated / Uninsulated WallsSlide14

Wood and Brick FramingSlide15

Cellulose Insulation RetrofitsSlide16

Closed-cell P

olyurethane Spray-on Foam InsulationAll closed-cell polyurethane foam insulation made today is produced with a non-CFC (chlorofluorocarbon) gas as the foaming agent.

PU foam is

water-vapor permeable

remains flexible

fire resistant

provides

good air

sealing

R-3.6 to R-6.5 per inch thickness

Soy-based

, polyurethane liquid

spray-foam

also

available.