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Encyclopedia of Insulation Engineering & Materials

A technical reference for engineers: heat and moisture physics, advanced materials, technical datasheets, application matrix and QA/QC tests.

Engineering glossary

Thermal conductivity (k)
Heat flow through one metre of material per degree of temperature difference; lower is better insulation (W/m·K).
Thermal resistance (R)
Layer thickness divided by conductivity (R = d/k); resistances of successive layers add up.
Thermal transmittance (U)
The inverse of the whole assembly's total resistance including surface films; the value the code limits.
Thermal bridge
Where the insulation layer is interrupted (beams, edges, openings), letting heat through faster.
Dew point
The temperature at which water vapour condenses; key to avoiding condensation under coatings and within walls.
Vapour resistance factor (μ)
How much a material resists water-vapour diffusion relative to air; guides vapour-barrier placement.
Vapour barrier
A low-permeance layer on the warm side of an assembly that stops vapour reaching layers where it would condense.
Dry film thickness (DFT)
Coating thickness after curing, measured in microns or millimetres to verify the specification.
Holiday (spark) test
An electrical test that finds pinholes in insulating coatings such as epoxy and polyurea.
Pull-off adhesion test
Measures the force to detach a bonded dolly, assessing how well a coating bonds to the substrate.
Flood test
Flooding a roof or tank for a set time after waterproofing to confirm there are no leaks before covering.
Closed-cell
Foam whose cells are mostly closed, resisting water uptake with lower conductivity and higher rigidity.
Aliphatic / aromatic
Isocyanate types in polyurea and polyurethane; aliphatic keeps its colour in sun, aromatic yellows and needs a topcoat.
APP / SBS
Bitumen modifiers in membranes: plastomeric APP tolerates heat, elastomeric SBS is more flexible.
Crystalline waterproofing
A cementitious product that reacts with moisture in concrete to grow crystals that block pores and fine cracks.
Cant strip
A sloped fillet where roof meets wall so the waterproofing doesn't fold at a sharp right angle.
Concrete surface profile (CSP)
Standard grades of concrete roughness after mechanical preparation, matched to the coating system.
Solar reflectance (SRI)
An index of a roof surface's ability to reflect sun and shed heat; higher for white reflective coatings.

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