2000-P02165 - addn/remodel/repair

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• MINNESOTA ENERGY CODE All Buildings SUMMARY OF BASIC CATEGORY 1 AND CATEGORY 2 BUILDING REQUIREMENTS FOR INSULATION PROTECTION,AIR TIGHTNESS,AND VENTILATION MINIMUM: All buildings must meet the following minimum code requirements: VENTILATION: A Category 2 building is one where infiltration and passive ventilation(operable windows)are relied on to provide necessary year-round ventilation. If one or more of the Category 1 measures below is incorporated into the residential design,however,a residential mechanical ventilation system as specified below must be installed. . VAPOR RETARDER: A vapor retarder,also known as a moisture barrier or vapor barrier,must be installed on the warm side of insulated ceilings,walls and floors. Polyethylene vapor retarders must be 4-mills or thicker. The code requires a vapor retarder to be installed only on rim joists that are susceptible to condensation from moisture diffusion. AIR BARRIER: A barrier against air leakage must be installed to prevent leakage of moisture-laden air from the conditioned space into exterior ceilings,walls and floors. • Plumbing and heating penetrations must be air sealed. An air barrier must be provided behind any tub or shower that is located on an exterior wall. • Air sealing must be done at all dropped ceiling areas,chimney flues,ventilation ducts,and other fire stops that penetrate the vapor retarder. • Holes in the building envelope for electrical and telecommunications equipment must be air sealed, including the service entrance,wires,conduit,cables,panels,recessed light fixtures,and fans(where vapor retarder is penetrated). • Joints in the building envelope must be sealed, including around window and door frames, between wall cavities and window or door frames. • •Tested air infiltration rates must not exceed 0.34 cfm/square foot of operable sash crack for windows, 0.5 cfm/square font for residential doors and 1.25 cfm/square foot for commercial doors. WIND WASH BARRIER: An air-impermeable barrier must be installed at the attic edge(baffles must be rigid material resistant to wind driven moisture);and overhangs,such as cantilevered floors and bay windows. IOPTIONAL: Category 1 Buildings meet all requirements as listed above plus the following: RESIDENTIAL MECHANICAL VENTILATION SYSTEM FOR RESIDENTIAL BUILDINGS: A system that,by mechanical means, is capable of introducing and distributing outdoor air to all habitable rooms and removing indoor air at a rate of not less than 035 air changes per hour or 15 cfm per bedroom plus another 15 cfm, whichever is greater. AIR LEAKAGE BARRIER: A barrier against air leakage must be installed to prevent leakage of moisture-laden air from the conditioned space into the building envelope: • Electrical boxes and fan housings must also be sealed. • All rim joists,band joists,and where floor joists or trusses meet outer walls must be sealed. • The top of interior partition walls that join insulated ceilings must be sealed. • Joints must be sealed between wall assemblies and their rim joists,sill plates,foundations, between wall and roof/ceilings,and between separate wall panels. WIND WASH BARRIER: All exterior joints in the building envelope that may be sources of air leaks must sealed. This is a summary only. Other requirements may apply. See the Minnesota Energy Code. 2/5/96 Questions? Call Department of Public Service Information Center at 612/296-5175 or 1-800/657-3710. o,.