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Posted: January 14, 2010 with reprint permission from www.energycode.com
Tutorial explaining the Title-24 kitchen lighting requirements; a Title-24 Residential
Lighting Guide; and a summary of the Title-24 residential lighting requirements: www.energycode.com/?page_id=96
February 12,
2010 Webinar/class that addresses the new changes to the residential Title-24 lighting & ventilation code.
www.energycode.com/?p=376
2008 New Title-24 Energy Code Summary of Changes
The effective date for the 2008 Title-24 Building Energy Efficiency Standards
has been pushed back to January 1, 2010 and incorporate new measures to reduce energy use and greenhouse gas emissions.The new 2008 energy code is
significantly more restrictive however introduce a number of new energy credits that can be used to leverage a project into compliance in a cost effective manner.
This week we’ll address the changes to the residential standards:
The U-factor and SHGC (Solar Heat Gain Coefficient) requirements have been
increased.The base-line, standard window required for compliance with most prescriptive packages is dual pane/vinyl window with Low-E, spectrally
selective coating.Standard dual pane/metal framing windows even with a thermally broken gasket isolating the glazing from the framing will not comply with the new standards.
The new Title-24 residential lighting requirements divide the home into three
distinct zones that are treated very differently.The first zone is the kitchen.The kitchen lighting requirements retain the same compliance formula as in the 2005 standards known as the 50% rule. 50% of the total kitchen lighting watts must be high efficacy (compact fluorescent, LED, Linear
fluorescent). The balance of the kitchen lighting can be low-efficacy.However there is now a new provision for lighting that is internal to the cabinets for
illuminating the inside of the cabinet up to 20 watts of low or high efficacy lighting power per linear foot of illuminated cabinet.These fixtures internal to
the cabinets can be low efficacy if desired with no penalty.
The second zone includes all the bathrooms, garages, laundry rooms, and
utility rooms which must have either high efficacy fixtures or they must have vacancy sensors installed that control the low efficacy fixtures.Note that
these must be vacancy sensors, not occupancy sensors.A vacancy sensor is a variation of an occupancy sensor however instead of automatically turning on
with someone enters a room you must manually operate the switch to turn the lights on.Then after you leave the room the sensor detects that the room is
vacant and will automatically turn the lights off.The logic behind this manual-on function is that often you may want to quickly enter into a
bathroom that is well-lit during the daytime to simply wash your hands or retrieve some toiletries and not need to turn on the lights at all, thus saving
energy.If you need the light switched on then you have that option but the sensor won’t turn them on for you but will turn them off automatically after you leave.
The third zone includes all the hallways, dining rooms, family rooms, home
office, and bedrooms.These rooms have the most lenient requirements as they must have either high efficacy lighting or low efficacy fixtures controlled by a
vacancy sensor or be controlled by a dimmer.The dimmer option allows the most cost effective way to comply while providing the most flexibility and options in allowable fixtures.
New indoor ventilation requirements mandate that all low-rise residential
buildings must have a whole house ventilation system that provides a calculated minimum amount of outdoor air by using either a continuously
running bathroom fan or a supply or return air ventilation thru a central HVAC system.The minimum ventilation volume must be a minimum of 1 cfm for each
100 sq. ft. of floor area plus 7.5 cfm for each occupant.The number of occupants is determined by multiplying the number of bedrooms and then
adding one.For example a 3 bedroom, 1,800 square foot townhouse would require 48 cfm of continuous ventilation.
New HVAC systems must prescriptively comply with new refrigerant charge,
proper airflow, and fan watt draw verification inspections performed by certified HERS raters. Duct testing is another HERS verification inspection that
was an optional compliance credit in the 2005 standards but now is a standard prescriptive requirement in the 2008 standards. In addition for the first time
the new standards will track the time of energy use in the compliance algorithms.A home that experiences its greatest energy use and solar load
during peak electrical cost periods will be severely penalized in the new energy code and find it very difficult to comply.Homes that are use strategies to shift
energy use to off-peak hours will realize large credits in the compliance calculations that can be used to offset other design priorities such as larger
windows or a challenging on-site building orientation.
New HERS measures have been introduced requiring third-party, independent
verification such as airtight air handler boxes, high efficient furnace fans, refrigerant charge indicator displays (CID) and correctly sizing the air
conditioner, all new for 2008.These HERS measures are Title-24 credits that can be traded-off for other more flexibility in other areas of the home or can
also be used to bring the project into compliance with state and utility incentive programs that provide financial rewards for exceeding the basic Title-24 requirements.
For the first time Title-24 compliance documentation must be electronically
uploaded to a database registry which can be accessed by building department officials to verify compliance.This will begin on January 1, 2010 for tract homes
required multiple orientation submittal and HERS measures but will expand to all projects requiring HERS measures in October, 2010.Overall the new 2008
Title-24 Building Energy Standards are roughly 15% more restrictive than the previous 2005 standards they replace.
SOURCE URL: www.energycode.com/?page_id=228
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