The 2009 International Residential Code and International Energy Conservation Code do not permit trade-offs for installing high-efficiency heating, ventilation, and air conditioning equipment—installing a 90%+ furnace as a trade-off for 2" x 4" stud walls with R-13 insulation. The more permanent building insulation and sealing features now take precedence. However, there still remain optional strategies allowing 2" x 4" exterior stud walls.
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Converting a basement to conditioned space increases the living space of a house. As with most construction activities, the conversion or remodeling must be done in compliance with construction codes in force at the time the remodel permit is issued. Compliance shall be demonstrated by meeting the requirements of the 2009 International Energy Conservation Code.
Converting an existing unconditioned garage to conditioned space is a popular strategy for increasing the living space of a house. Typically, the conversion or remodeling must be done in compliance with construction codes in force at the time the remodel permit is issued. Compliance shall be demonstrated by meeting the requirements of the 2009 International Energy Conservation Code.
Codes allow crawlspaces with mechanical ventilation instead of crawlspaces with passive vents to the outdoors. However, code officials and builders are often uncertain about the design details.
Metal or plastic drywall clips can be used to replace a third stud at a corner, at a partition intersection backing stud, or in the ceiling to replace a nailer. The reduced attachment (wood to drywall) resulting from the use of dry wall clips allows small movements without drywall cracking and nail pops.
Many studies have shown that visual inspection of duct seals in residences is not enough. Code now requires a pressure test. Pressure testing ducts as required by the 2009 International Energy Conservation Code is far superior to visual inspection and will definitively confirm that duct leakage is kept to a low level.
The 2009 International Energy Conservation Code defines conditioned space as an area or room within a building being heated or cooled, containing uninsulated ducts, or with a fixed opening directly into an adjacent conditioned space. Various studies have identified compelling reasons for locating all heating, ventilation, and air conditioning ducts and air handlers within this conditioned space.
Headers for windows and doors are typically supported by cripples or jack studs. These studs can be eliminated using header hangers, as allowed under the International Residential Code.
Lighting consumes more than 10% of electric energy used in homes, presenting a substantial opportunity for lowering residential energy consumption. The International Code Council recently passed a code change that will appear in the 2009 International Energy Conservation Code and the International Residential Code requiring that half of the permanent lighting in a new home have high-efficacy lamps.
The intent of the pipe insulation requirements is to reduce temperature changes while fluids are being transported through piping associated with heating, cooling or service hot water (SHW) systems, thereby saving energy and reducing operating costs.
The use of header stock over windows and doors in nonbearing walls is typical construction practice throughout the industry. But a single two-inch by four-inch board is allowed to be used as a header in non-load bearing wall systems..
The 2009 International Energy Conservation Code, Section 403.2.2, requires that duct systems be pressure tested, or all ducts and air handlers be located in conditioned space. Building cavities used to convey return air located over a crawlspace or next to an unconditioned space would be required to be tested.
Over the past several code cycles, mechanical ventilation requirements have been added to ensure adequate outside air is provided for ventilation whenever residences are occupied. These ventilation requirements can be found in the International Residential Code for homes and the International Mechanical Code for dwelling units in multifamily buildings.
The 2006 and 2009 International Energy Conservation Code require sizing calculations be performed on every home by referencing International Residential Code Section M1401.3. Section M1401.3 requires heating and cooling systems be sized to the Air Conditioning Contractors of America (ACCA) Manual J - Eighth Addition or other approved heating and cooling load calculations. The ACCA sizing methodology has sufficient built-in safety factors to accommodate most conditioning needs.
Rigid board insulation (foam plastic) is an effective draft stop, while providing part of the required R-value of the attic kneewall, if installed on the attic side of the kneewall.
A single top plate is allowed under the International Residential Code, but it is not a common construction practice. The standard practice for exterior and interior wall framing is using a double top plate to connect wall segments, and to support framing above the plates.
Adequate attic ventilation is a long-standing requirement in building codes for moisture control. However, unvented attics can reduce residential energy needs, and are allowed by the code under certain conditions.
Section R806.4 of the 2009 International Residential Code® (IRC), and Section R806.5 of the 2012 IRC have requirements for unvented (conditioned) attic assemblies.
Condensing dryers can be useful in situations where the laundry room is located a significant distance from an exterior wall to which it can vent. By eliminating long dryer vent runs, they eliminate possible moisture condensation problems in that run.