Whole-Wall Thermal Performance
The Whole-Wall Thermal Performance Calculator
provides an on-line, interactive method for determining
the whole-wall R-value for a variety of wall systems and house plans. The Whole-Wall
Thermal Performance Calculator makes use of a database of results from detailed
thermal analyses performed by Jan Kosny (kyo@ornl.gov) using the HEATING finite-difference
heat transfer computer program. Graphics of wall structural details and building floor
plans were developed by Gail Snodgrass.
However, the R-value does not fully define the performance of a wall system.
There are at least four phsical attributes of a wall system that must be
considered when investigating whole-wall thermal performance:
whole-wall R-value
thermal mass benefit description - thermal mass benefit calculator download
airtightness
moisture tolerance
For some systems all four of the factors are important; for
others, only the first is relevant. A fifth factor, which is not listed
because of uncertainty of how to calculate it accurately, is sustainability.
As this field matures, it may be desirable to add this element.
For more information, contact the program manager for Building Envelope Research:
André O. Desjarlais
Oak Ridge National Laboratory
P. O. Box 2008, MS 6070
Oak Ridge, TN 37831-6070
E-mail Andre Desjarlais
Revised: May 3, 2005 by Brett Carmichael