Article #1456 - REScheck Webcast Questions - Roof and Ceiling
This article is based on questions asked during both the May 6, 2005
REScheck Training Webcast
and the July 28, 2005
as well as questions received through email following these events. The original language of the questions and answers has been modified to make them as generic as possible while retaining the applicable specific information.
Is there a distinction between roof area and ceiling area? Roof area is usually larger, but conditioned space only connects to attic through ceiling area, not roof.
The ceiling area should be measured on the slope of the finished interior surface.
What area do you use for a scissor truss, the foot print or the area insulated?
The ceiling area should be measured on the slope of the finished interior surface.
We use R-11 batts between the roof trusses and then blow in R-19 on top of that; can I show this as R-11 in cavity and the R-19 is continuous value?
The total R-value should be entered as cavity. The software automatically calculates insulation that is assumed to be over the trusses and treat as continuous.
How do you measure the bevel along the insulation, the lower or upper part of the angle?
In the case of the ceiling, RES
check
accounts for the bevel in the calculations and thus you would enter the full called out R-value of the insulation. For details on the calculations used, refer to our
Methodology for Developing the REScheck Software through Version 3.6
Document.
On attic trusses, do you use wall insulation or roof insulation on the vertical part of the truss?
Use roof insulation; the wall stops at the top plate.