Item 3

Plain English

The state of California has very specific and rather stringent energy conservation standards, usually called "Title 24." If you honestly can state that your existing building contains a functioning heater of any size, the work you are doing is considered to be an alteration of heated space rather than creation of new conditional space; you therefore do not need to touch the envelope of the building– i.e. windows, walls, roof, doors –for purposes of energy conservation. On the other hand, if your design complies entirely with the "prescriptive heating requirements" as specified in section 329B.6, the space in question is considered "unconditioned," which means it does not require Title 24 energy calculations.

HINT: There is, however, a conflict. The prescriptive heating requirements–a default set of requirements for live/work intended to simplify requirements and avoid the need for Title 24 calculations-- dictate a certain level of heat delivery as well as insulation of walls and ceiling of the heated space(s). Therefore, a conflict arises between the above permission to leave the envelope alone and the prescriptive insulation requirements.

Resolving this conflict can be difficult in large existing buildings, particularly those combining wood frame floors and interiors with masonry or concrete exterior walls, a very common early 20th century building type, and one favored for conversion by today’s live/work developers. Pending resolution of this inconsistency, one choice is to commission a computer-generated set of Title 24 calculations, which will usually contain recommendations for added insulation, possible window changes, and other alterations. Such construction can be expensive, especially if not otherwise necessary. Most all-concrete or masonry buildings have sufficient "thermal mass" which means that when a Title 24 calculation (usually costing $150-400) is run on them they do not require significant building envelope modifications.

A good direction for addressing heat and insulation issues, suggested by Building Department staff, is that in a building which has any pre-existing heat, conform to the prescriptive heating requirements, add thermal insulation to the roof and any wood frame exterior walls to comply with all prescriptive requirements, but do not upgrade exterior windows (other than making them relatively water-tight) and do not alter (or insulate) masonry or concrete walls.

In any event, whatever energy calculations or prescriptive standards are being employed should be noted under this section, itemized by unit if there is variation. Please see the example in the appendix.


The California Energy Commission Standards (Residential or Non-residential) which are being applied and the areas of the building and the individual JLWQ to which they are being applied and show the required energy documents within the plans;

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