Comparison of REM/Design models to post-construction performance
It seems like REM/Design is one of the tools commonly used by some of the pros participating here. I’ve been working with it some and it seems like a good tool.
Judging from the complexity of building geometries, materials, and all the different factors that go into designing a building I’m figuring that it’s difficult, if not impossible, for any thermal modeling program to be completely accurate in predicting a home’s heating and cooling loads.
I’ve been using REM/Design two ways. One is as a means to compare the relative impact of different design approaches such as amount of window area, window U & SHGC values, performance differences between various SIP thicknesses and SIP materials, etc.
The other way I’m using it is to try to get a ballpark idea of what the heating needs will be for my planned home design. I believe the results REM/Design is producing are reasonably accurate but I have no way to be sure of this.
I was therefore wondering if anyone on this forum who has used REM/Design has ever done any follow up to see how close the thermal performance of the home(s) they’ve designed actually was when compared with the heating loads estimated during design phase modeling?
My real goal is to try to avoid significantly over or under sizing the heating system and to choose the right heating system design approach based on the results that the thermal modeling yields. I’m basically just trying to get a feel for what type of fudge factor would be prudent to apply to the results yielded by the modeling, assuming that I’ve entered all of the parameters correctly into the tool.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part