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Air Barrier by Joseph W. Lstiburek — last modified 2007/05/21
Air barriers are systems of materials designed and constructed to...
Air Retarder by Joseph W. Lstiburek — last modified 2007/05/21
Materials and assemblies that do not meet the performance requirements of...
Conditioned Space by ASHRAE Standard 62.2 — last modified 2007/05/21
The part of the building that is designed to be thermally conditioned for the...
Diffusion by Joe Lstiburek — last modified 2006/06/11
The movement of individual molecules through a material...
Drainage Plane by Joseph W. Lstiburek — last modified 2007/05/21
Drainage planes are water repellent materials (building paper...
Equivalent Leakage Area of a Building (EqLA or ELA) by Joe Lstiburek — last modified 2006/06/11
Quantitative expression of the airtightness of a building enclosure...
Foundation, Water-managed by Joe Lstiburek — last modified 2006/06/11
Systems for at or below-grade enclosure assemblies...
Grade Beam by Joe Lstiburek — last modified 2006/06/11
A foundation wall that is cast at or just below the grade...
Housewrap by Joe Lstiburek — last modified 2006/06/11
Any of the numerous spun-fiber polyolefin rolled sheet goods...
Indoor Air by ASHRAE Standard 62.2 — last modified 2007/05/21
Air in a conditioned space.
Insulating Sheathing by Joe Lstiburek — last modified 2006/06/11
Non-structural insulating board products with varying R-values...
Jump Duct by Joe Lstiburek — last modified 2006/06/11
A flexible, short, U-shaped duct...
Kiln-dried Lumber by Joe Lstiburek — last modified 2006/06/11
Any lumber placed in a heated chamber or "shed" to reduce its moisture content...
Low-E by Joe Lstiburek — last modified 2006/06/11
Most often used in reference to a coating for high-performance windows...
Mechanical Ventilation by Joe Lstiburek — last modified 2006/06/11
Controlled, purposeful introduction of outdoor air to the conditioned space.
Outdoor Air by ASHRAE Standard 62.2 — last modified 2007/05/21
Air outside the building.
Ozone by Joe Lstiburek — last modified 2006/06/11
This 3-atom molecule is an even more active oxidizing agent than its more common 2-atom relative . . .
Pressure Boundary by ASHRAE Standard 62.2 — last modified 2007/05/21
The primary air enclosure boundary separating conditioned air and unconditioned...
Thermal Boundary by Joe Lstiburek — last modified 2006/06/11
The layer in a building enclosure that controls the transfer of energy...
Vapor Barrier by Joseph W. Lstiburek — last modified 2007/05/23
A vapor barrier is a material that has a permeance of...
Vapor Impermeable by Joseph W. Lstiburek — last modified 2007/05/21
Materials with a permeance of 0.1 perm or less...
Vapor Permeable by Joseph W. Lstiburek — last modified 2007/05/21
Materials with a permeance of greater than 10 perms...
Vapor Retarder by Joseph W. Lstiburek — last modified 2007/05/21
A vapor retarder is a material that has a permeance of...
Vapor Semi-Impermeable by Joseph W. Lstiburek — last modified 2007/05/21
Materials with a permeance of 1.0 perm...
Vapor Semi-Permeable by Joseph W. Lstiburek — last modified 2007/05/21
Materials with a permeance of 10 perms...
Water Resistant Barrier by Joe Lstiburek — last modified 2006/06/11
A water resistant barrier (WRB) is also referred to as a drainage plane...
Wind-Washing by Joe Lstiburek — last modified 2006/06/11
The phenomenon of air movement that occurs due to wind...
Xeriscaping by Joe Lstiburek — last modified 2006/06/11
Climate-tuned landscaping that minimizes outdoor water use...
Zero Energy House by Joe Lstiburek — last modified 2006/06/11
Any house that averages out to net zero energy consumption...
Permeance by Joe Lstiburek — last modified 2006/06/11
The physical property that defines the ease at which water molecules...
R-value by Joe Lstiburek — last modified 2006/06/11
Quantitative measure of resistance to heat flow...
U-factor by Joe Lstiburek — last modified 2006/06/11
Quantitative measure of heat flow or conductivity...
Ventilation by John Straube — last modified 2006/06/11
The intentional flow of air into occupied spaces . . .
Wind Washing by John Straube — last modified 2006/06/11
The effect of wind-driven air movement through air permeable insulation reduces its insulating value . . .
Water Resistant Barrier by John Straube — last modified 2006/06/11
A sheet, spray- or trowel-applied membrane or material layer . . .
Sourced Drained by John Straube — last modified 2006/06/11
Another term for a face sealed system . . .
Sheathing Membrane by John Straube — last modified 2006/06/11
A generic term for a membrane layer that prevents the resists the passage of liquid water and possibly air and vapor . . .
Sealant by John Straube — last modified 2006/06/11
A flexible, polymer-based elastomeric material . . .
Semi-rigid Insulation by John Straube — last modified 2006/06/11
Board material which provides thermal resistance comprised of mineral fibers . . .
Rigid Insulation by John Straube — last modified 2006/06/11
Rigid board material which provides thermal resistance . . .
Radiation by John Straube — last modified 2006/06/11
A form of energy in electro-magnetic radiation . . .
Psychrometrics by John Straube — last modified 2006/06/11
The study of air and its energy and water vapour contents.
Joints by John Straube — last modified 2006/06/11
An interface between elements . . .
Flashing by John Straube — last modified 2006/06/11
A waterproof material used to redirect or shed drained water, or occasionally to act as a capillary break . . .
Expansion Joint by John Straube — last modified 2006/06/11
A structural separation between building elements . . .
Air Barrier; Performance Requirements by Joseph W. Lstiburek — last modified 2006/12/05
Air barrier systems typically are assembled from materials incorporated in . . .
Building Enclosure by Joseph W. Lstiburek — last modified 2007/05/22
A building enclosure is the component (typically comprised . . .
Mold by Joseph W. Lstiburek — last modified 2006/12/05
Mold is one type of fungus which is different from plants, animals and . . .
EIFS (external insulation finishing system) by Joseph W. Lstiburek — last modified 2006/12/05
A combination of insulation and stucco system cladding for . . .
Spectrally Selective Glazing by Joseph W. Lstiburek — last modified 2006/12/05
These types of window systems reduce solar gain while still providing daylighting . . .
Hygroscopic by Building Science Corporation — last modified 2006/12/05
Materials that change their permeability characteristics as relative humidity . . .
Hydrophobic by Joseph W. Lstiburek — last modified 2006/12/05
Materials that do not change their permeability as a function of relative . . .
Commissioning by Joseph W. Lstiburek — last modified 2006/12/05
Prior to occupancy, testing and inspections should note any problems and they . . .
Air Barrier System by Joseph W. Lstiburek — last modified 2007/05/22
An air barrier system is an assembly of materials that together . . .
Air-impermeable by Joeseph W. Lstiburek — last modified 2007/05/21
A material or assembly having an air permeance equal to or less than...
Occupiable Space by ASHRAE Standard 62.2 — last modified 2007/05/21
Any enclosed space inside the pressure boundary and ...
Habitable Space by ASHRAE Standard 62.2 — last modified 2007/05/21
Building space intended for continual human occupancy. Such space generally...
Vapor Control Layer (or Layers) by Joseph W. Lstiburek — last modified 2007/05/21
The element (or elements) that is (or are) designed and installed...
Vapor Permeance Classes by Joseph W. Lstiburek — last modified 2007/05/21
Test procedure for determining vapor permeance class is...
Subflorescence/Sub-efflorescence by John Straube — last modified 2007/06/05
A potentially harmful accumulation of water soluble salts that . . .