Manual J - Residential Load Calculation 8th Edition is the national ANSI-recognized standard for producing HVAC equipment sizing loads for single-family detached homes, small multi-unit structures, condominiums, town houses and manufactured homes. It also accommodates homes that have exceptional architectural features and life style accessories such as dwellings that have limited exposure or no exposure diversity; homes with large south-facing glass area or rooms with unusually large glass areas; thermally isolated solariums; customized internal load estimates. The publication was updated to version 2.10 in 2011 and now includes wider variety of reference information including encapsulated attic tables and instructions; duct dew-point equations, and winter humidification loads for duct leakage calculation procedures. The publication is sensitive to an increased variety of issues related to construction materials and methods. A proper load calculation performed in accordance with the Manual J procedures, is required by national building codes and in many state and local jurisdictions.