As seen, we bring new terms to construction, even for specialists.
We will list those terms and shortly explain them, following that the theory and practice to give value to the benefits associated with this new idea.
Non-Permissive – The term represents the ELIMINATION of all ways in which water/air/vapor leakage or movement negatively affects and interacts with an insulation applied to an enclosure. Some examples are as follows: vapor diffusion, enclosure air flow (air-tightness), infiltration/ex-filtration, wind washing or forced convection, convection in air permeable insulation, looping through gaps around insulation, water absorption, and capillarity. In the “non-permissive” insulation, all those factors are eliminated, leaving only the thermal conduction and heat flow analysis with the presumption that the problems of condensation are eliminated.
Principle of Avoiding Condensation – the principle of the technology that expresses in short how condensation can be avoided in building enclosures exposed to differences of temperatures; this principle would be the base of a building science based on elimination of the condensation phenomenon.
Vapor Impermeable Insulation (VII) – insulation impermeable to vapors (Class I, less than 0.1 Perm); also impermeable to water and air.
Non-Permissive Insulation Assemblies (NP-IA)–continuous vapor impermeable insulation created by assembling Vapor Impermeable Insulation VII elements, with joints sealed so as the characteristics of VII to be extended to the entire area considered as insulation system.
NP-EIFS – invented Non-Permissive Exterior Insulation and Finish Systems, which integrates the new concept of non-permissive insulation with the technology that makes this concept possible and the details that ensures the success of the technology.
EIOS – (Exterior Insulation Over-Specified) world's first insulation system that claims the elimination of condensation phenomenon in building envelopes, in addition to all other inconvenient issues; EIOS is the brand name that put in practice the concept, technology, and details of NP-EIFS to eliminate condensation.
Drying Effect – we call this phenomenon Unidirectional Drying, when water only dries out and is not accumulated by condensation; a phenomenon observed as soon as a difference of temperature is applied to the enclosure (e.g. heating inside), the wood substrate of EIOS starts drying; this effect makes EIOS the world's first insulation wall system that dries when differences of temperatures are applied, while every other insulated wall systems increases its humidity.
Environmental Separator – Term used for non-permissive insulation or insulation assembly that creates a total separation with no physicochemical interactions between warm-humid and cold-dry environments, allowing only a low heat transfer.
Regarding new terms related to avoiding condensation, we strongly recommend that Vapor Impermeable Insulation and Vapor Impermeable Insulation Assemblies to be referred as Non-Permissive Insulation or similar to the above and not as air/vapor control or moisture control layers as used for wall systems. This will cause future confusion, misinterpretation, and improper decisions.