Heating/Ventilation/Air-Conditioning (HVAC) Questions and Concerns

Are windows required in home theaters?

No. In lieu of natural lighting and natural ventilation requirements, artificial light and whole-house mechanical ventilation may be used. Reference section R303.1, I.R.C. for exceptions. ***Please note: The required artificial lighting must be hard-wired room light fixtures. The required whole-house mechanical ventilation system must be designed in compliance with section M1507, I.R.C., and so shown on the drawings.

I want to enclose my existing covered patio and create a habitable living space. Are there any nonstructural code issues I should be concerned about?

Yes. As an example, you CAN NOT enclose your existing covered patio, if the only “emergency escape and rescue opening” (refer to General Building Code Terms for definition), from an existing bedroom, opens into this existing patio area. All “emergency escape and rescue openings” must open directly to the building’s exterior, and may not go through an adjoining room.

In addition, once the covered patio space is enclosed, the existing adjacent habitable rooms that once relied on exterior operable windows/doors (that directly opened to the patio), may no longer meet the minimum natural lighting and/or natural ventilation code requirements. Reference section R303, I.R.C., for exceptions. Another concern is the sizing of the existing heating/ventilation/ air conditioning (HVAC) unit to properly accommodate this newly added conditioned space. The existing HVAC unit may have to be replaced with a larger unit. An HVAC contractor/installer should be consulted.

I have an outdoor (concrete slab mounted) A/C unit that is old and needs to be replaced. A heating/ventilation/air conditioning (HVAC) contractor suggested a rooftop mounted unit. Does the City allow new units to be rooftop mounted.

No. The City no longer allows new residential A/C units to be mounted on a roof.

Does my outdoor A/C unit need to be mounted on a foundation?

Yes. The A/C unit must be located on a supporting foundation raised at least 3 inches above the adjacent grade and must be level and conform to the manufacturer’s installation instructions, to provide access and proper operating clearances around the unit. ***Please note: Newly installed exterior mounted A/C units located in side and rear yards must not obstruct fire access and emergency rescue/egress (minimum 36-inch clear width) to and from any perimeter portion of the residence.

My interior lights are starting to dim when the A/C unit first starts up. What is wrong?

You need to consult with your heating/ventilation/air-conditioning (HVAC) service contractor/installer. It could be a number of things, including a weak start-up capacitor, loose neutral wire connection, ect. (refer to General Building Code Terms for Definition of A/C unit).

Do I need to have a permanent hardwired light fixture and switch in my attic for use to service the attic mounted HVAC equipment unit?

Yes, section M1305.1.3.1, I.R.C. requires a luminaire controlled by a switch (located at the required attic passageway access opening) and a receptacle outlet installed at or near the attic mounted HVAC equipment unit.

Do all HVAC equipment units need an approved service disconnect?

Yes, a readily accessible disconnect device is required within sight of the installed HVAC equipment unit, section E4101.5, I.R.C.