C505.1
General. Buildings or spaces undergoing a change in space
conditioning alteration shall comply with Sections C505.2 and C505.4. Buildings
or spaces undergoing a change in occupancy alterations shall comply with
Sections C505.3 and C505.4. Spaces changing from one use type to another shall
comply with Section C505.5.
Buildings or spaces undergoing a change in space conditioning,
change in occupancy or use shall conform to the provisions of this code without
requiring the unaltered portion of the existing building to comply with this
code. Alterations shall be such that the existing building or structure is no
less conforming to the provisions of this code than the existing building or
structure was prior to the alteration.
A change in space conditioning alteration shall be deemed to
comply with this code if the alteration area alone complies or if the
alteration area is combined with all other spaces within the existing building
that are of the same space conditioning category according to Section C505.2 to
demonstrate compliance. A change in occupancy alteration shall be deemed to
comply with this code if the alteration area alone complies or if the existing
building and the alteration area are combined to demonstrate complete for the
whole building. This allowance applies to prescriptive compliance in accordance
with Section C505.4 or total building performance in accordance with Section
C407.
Buildings or spaces that were permitted prior to the 2009
Washington state energy code, or were originally permitted as unconditioned,
may comply with this section as follows:
1. Where the component performance
alternative in Section C402.1.5 is used to demonstrate compliance with this
section, the Proposed Total UA is allowed to be up to 110 percent of the
Allowable Total UA. This exception may be applied to the project area alone, or
to the existing building and project area combined as a whole
building.
2. Where total building
performance in accordance with Section C407 is used to demonstrate compliance
with this section, the total annual carbon emissions from energy consumption of
the proposed design is allowed to be up to 110 percent of the annual carbon
emissions from energy consumption allowed by Section C407.3. This exception may
be applied to the project area alone, or to the existing building and project
area combined as a whole building.
C505.1.1
Additional energy efficiency
credits. Buildings or spaces that are required to comply with Sections
C505.2 or C505.3 shall also comply with Section C502.1.1 in the same manner as
an addition.
C505.1.2
Renewable energy. Buildings or spaces that are required to comply
with Section C505.2 or C505.3 shall also comply with Section C502.1.2 in the
same manner as an addition.
C505.2
Change in space
conditioning. Spaces undergoing a change in space conditioning
alteration shall be brought up to full compliance with this code for all
disciplines in the following cases:
1. Any low
energy space in accordance with Section C402.1.1.1 that is altered to become
conditioned space or semi-heated space shall
be brought into full compliance with this code.
2. Any semi-heated space in accordance with
Section C402.1.1.2 that is altered to become conditioned space shall be brought
into full compliance with this code.
For buildings with more than one space conditioning category,
the interior partition walls, ceilings, floors and fenestration that separate
space conditioning areas shall comply with the thermal envelope requirements
per the area with the highest level of space conditioning.
C505.3
Change in occupancy.
Spaces undergoing a change in occupancy alteration shall be brought up
to full compliance with this code for all disciplines in the following cases:
1. Any space that is converted from a Group
F, S or U occupancy to an occupancy other than Group F, S or U.
2. Any space that is converted to a Group R
dwelling unit or portion thereof, from another use or occupancy.
3. Any Group R dwelling unit or portion
thereof permitted prior to July 1, 2002, that is converted to a commercial use
or occupancy.
C505.4
Prescriptive compliance. Change in space conditioning and change
in occupancy alterations shall comply with Sections C505.4.1 through C505.4.6.
C505.4.1
Vertical fenestration.
A change in space conditioning alteration with vertical fenestration shall
comply with the following:
1. Where the
vertical fenestration area of the alteration combined with the vertical
fenestration area of all equivalent space conditioning areas in the existing
building results in a total vertical fenestration area that is less than or
equal to the maximum allowed by Section C402.4.1, the alteration shall comply
with Section C402.4.
2. Where the
vertical fenestration area of the alteration combined with the vertical
fenestration area of all equivalent space conditioning areas in the existing
building results in a total vertical fenestration area that is greater than the
maximum allowed by Section C402.4.1, the alteration shall comply with one of
the following:
2.1. Component performance
alternative with target area adjustment in accordance with Section C402.1.5 for
the alteration area of the building only.
2.2. Alteration area is combined with all
equivalent space conditioning areas to demonstrate compliance with the
component performance alternative.
2.3. Total building performance in accordance
with Section C407 for the alteration area of the building only.
2.4. Alteration area is combined with all
equivalent space conditioning areas to demonstrate total building performance
compliance.
C505.4.1.2
Skylights. A change in space conditioning alteration with
skylights shall comply with the following:
1.
Where the skylight area of the alteration combined with the skylight area of
all equivalent space conditioning areas in the existing building results in a
total skylight area that is less than or equal to the maximum allowed by
Section C402.4.1, the alteration shall comply with Section C402.4.
2. Where the skylight area of the alteration
combined with the skylight area of all equivalent space conditioning areas in
the existing building results in a total skylight area that is greater than the
maximum allowed by Section C402.4.1, the alteration shall comply with one of
the following:
2.1. Component performance
alternative with target area adjustment in accordance with Section C402.1.5 for
the alteration area of the building only.
2.2. Alteration area is combined with all
equivalent space conditioning areas to demonstrate compliance with the
component performance alternative.
2.3. Total building performance in accordance
with Section C407 for the alteration area of the building only.
2.4. Alteration area is combined with all
equivalent space conditioning areas to demonstrate total building performance
compliance.
C505.4.2
Building mechanical
systems. All new and existing mechanical systems and equipment that
serve the new building heating, cooling and ventilation needs of the alteration
area shall comply with Sections C403, C408.2, C409.5 and C501.6.
C505.4.3
Service water-heating
systems. All new and existing service water-heating systems and
equipment that serve the new service water-heating needs of the alteration area
shall comply with Sections C404, C408.3, C409.5 and C501.6.
C505.4.4
Pools and permanent
spas. All new and existing systems and equipment serving pools and
permanent spas that are included in the alteration shall comply with Sections
C404.11, C408.3, C409.5 and C501.6.
C505.4.5
Electrical power and lighting
systems and motors. All new and existing electrical power and lighting
systems and motors that are included in the alteration shall comply with
Sections C405, C408.4, C409.5 and C501.6.
C505.4.6
Refrigeration systems.
All new and existing refrigerated spaces and refrigeration systems and
equipment that serve the new refrigeration needs of the alteration area shall
comply with Sections C410, C408.7, C409.5 and C501.6.
C505.5
Change of use. Where the
use in a space changes from one use in Table C405.4.2 (1) or (2) to another use
in Table C405.4.2 (1) or (2), the installed lighting wattage in the space shall
comply with Section C405.4 and the ventilation air flow provided to the space
shall be in accordance with Chapter 4 of the International Mechanical
Code.
Notes
Wash. Admin. Code
§
51-11C-50500
Adopted by
WSR
16-03-072, Filed 1/19/2016, effective
7/1/2016
Amended by
WSR
19-02-089, Filed 1/2/2019, effective
7/1/2019
Amended by
WSR
19-24-040, Filed 11/26/2019, effective
7/1/2020
Amended by
WSR
22-14-091, Filed 7/1/2022, effective
7/1/2023