ACKNOWLEDGMENTS xi ,
1 INTRODUCTION 1
Heat-Loss Through Windows Must Be Reduced! 2
The Solution: Thermal Shutters and Shades 2
Additional Benefits 2
The Writer's Goal 3
Definitions of Shutters. Shades, Etc. 3
Is There Some One Best Choice of Shutter or Shade? 4
Use of a Mixture of Strategies 5
Functions of a Window 5
Main Types of Windows 6
Conventions Used in Descriptions and Drawings 8
Warnings 9
2 HOW IlEA T IS LOST THROUGH
WINDOWS 11
Typical Temperature Distributions
at Windows 12
Mechanisms of Energy Loss 13
What is Heat? 13
The Electromagnetic Spectrum 14
Amount of Power Radiated 15
Rate of Heat-Loss Through Window by Radiation 16
Rate ofHeat-Loss'Through Window by Conduction 17
Rate of Heat-Loss Through Windpw by Convection 19
Rate of Heat-Loss Through Welt..i'§ealed Window
on a Winter Night 21
Heat-Loss Through Well-Sealed Window During
Winter as a Whole 22
Circumstances That May Invalidate Predicted
Values of Heat-Loss 22 .
Relative Importance of Heat-Loss Through
Windows 23
JustIfication for Disregarding Solar
Energy Inflow 24
v