Comparison Library

Building performance, compared honestly.

A growing engineering knowledge base — written and reviewed by a Certified Passive House Designer — that explains how diagnostic methods, retrofit options and building-physics decisions genuinely differ. No marketing, just the building science you need to choose well.

Why these comparisons matter

Most building-performance mistakes are decision mistakes: the wrong test for the question, the wrong fix for the damp, a heat pump sized onto unimproved fabric. Each comparison sets out what each option actually does, the building physics behind it, the common misconceptions, and what a Certified Passive House Designer would recommend in real situations — so you can spend money where it counts.

Featured comparisons

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Every RetrofitIQ service has its own comparison cluster, growing over time.

Want this assessed on your own home?

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