AJAX progress indicator
  • r

  • Quantitative measure of an assembly or material resistance to heat flow for a unit temperature difference and a unit area. It is the reciprocal of the U-factor. The units for R-value are ft2 °F hr/Btu (English) or m2 °K hr/W (SI or metric). As R-value increases, conduction through an assembly(...)
  • The movement of energy by electromagnetic waves; can occur through a gas or a vacuum. One of the three modes of heat transfer (in addition to convection and conduction). At normal temperatures, radiation is in the infra-red region of the spectrum, whereas solar radiation is at visible(...)
  • A truss with a raised heel height, or the depth of the attic space at the eaves (the vertical distance from the top plate to the underside of the roof sheathing), measured at the outside wall. This leaves more room for insulation. Source:(...)
  • Randek develops, manufactures and markets high-performance machines and systems for prefabricated house manufacturing. The product range consist of: cut saws, wall floor and roof lines, roof truss system, butterfly tables and special machines. The automation level stretches from fully(...)
  • An individual, certified to perform Building Energy Efficiency Ratings for the building type and in the rating Class for which the Rater is certified. There are three classes of residential Rater certification: Class 3 - requiring the certified capability to complete Ratings based on(...)
  • A measure of the quantity of water vapor in a given volume of air, expressed as a percentage of the maximum quantity of water vapor that volume can contain before it becomes saturated (after which condensation will occur). Variants : RH Source: The Passivhaus Handbook
  • In April 1995, the National Association of State Energy Officials (NASEO) and Energy Rated Homes of America founded the Residential Energy Services Network (RESNET) to develop a national market for home energy rating systems and energy efficient mortgages. Source: Building Science Corporation