Tags: #architecture #buildingdesign #buildingscience #insulation #materialsscience

Total Effective R-value – the thermal performance of a total assembly in response to environmental factors and time.

Real-world R-values are mere portions of what we believe them to be. Yet the industry pats itself on the back after emerging enlightened and evolved from the thermal degradation that is stud cavity insulation. Cavity insulation bad, exterior insulation good. 

Not so fast. Conventional framed wall approaches are indeed thermally inefficient; but exterior C.I. can be just as inefficient and arguably much worse. Its efficacy assumes that exterior insulation is continuous – it isn’t. That it remains dry – it doesn’t. That it functions the same at all temperatures – it won’t. That it has immunity to the physics of convection – it can’t. That its performance is unaltered by time – sadly untrue. 

Insulation manufacturers often cherry-pick these inconvenient truths, using them against their competitors to gain a fleeting market advantage. And most architects and consultants fall right into it, turning tribal with shields and spears of bias and flimsy science – hoodwinked by flawed logic. It’s called building science grifting (i.e. marketing).

For continuous insulation to work (as intended), it must address the five points mentioned above. Few systems have figured it out. Those that have reflect an understanding that it’s not about the insulation itself but rather the whole assembly. 

Of late, I’ve had the privilege of seeing the inner-workings of some truly novel C.I. systems. Interesting advancements have been made. And more are just around the corner.