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City of Sonoma Building Department Informational Handout

Residential Window Replacement Requirements Handout No: 28

Revised: 1/17/20

✓ These requirements apply to the replacement of existing windows in residential buildings. “Replacement” means to replace the window with no modification of the size of the existing rough opening.

✓ Make sure you can meet all of the requirements before ordering your replacement windows.

✓ A building permit is required for the replacement of windows. Submit a building permit application and a floor plan showing and specifying that the window replacement will meet all applicable CA Residential Code (CRC) requirements. On the plan, provide a description of work and show the location of all replacement windows and doors, size of windows, U-value and solar heat gain coefficient (SHGC), type of operation, and the window sill height for required escape windows. Indicate the rooms that the windows serve, callout escape windows in bedrooms and indicate if safety glazing is required. Show locations of required smoke and carbon monoxide alarms. Complete and submit the CF-1R-ALT-WINDOWS form on the last page of this handout.

✓ Once installed, call for a building inspection (707-938-3681) and the Building Inspector will inspect for code compliance. Leave the NFRC Fenestration Labels on all new doors with glazing and windows until inspected and approved by the Building Inspector.

Safety Glazing: Glazing located in hazardous locations or subject to human impact must be provided with safety glazing materials that are identified as such with a permanent label. See City of Sonoma Informational Handout #37 (Safety Glazing Requirements) or the California Residential Code Section R308.4 for detailed requirements. Residential Window Fall Protection (CRC R312.2). Where the opening of an operable window is located more than 72 inches above the finished grade or surface below, the lowest part of the clear opening of the window shall be a minimum of 24 inches above the finished floor of the room in which the window is located unless:

1. The operable section of the window does not permit openings that allow passage of a 4-inch-diameter sphere; or

2. The window opening is provided with a window fall prevention device that comply with ASTM F2090; or

3. The window is provided with a window opening control device that comply with Section R312.2.2 of the CA Residential Code.

Smoke & Carbon Monoxide Alarms. (CRC R314 and R315). When building permits are issued for additions, alterations or repairs to residential buildings the 2019 California Residential Code requires the installation of smoke alarms and carbon monoxide alarms in accordance with, if they do not already exist.

Smoke alarms approved and listed by the State Fire Marshal shall be installed in each sleeping room, outside each separate sleeping area in the immediate vicinity of the bedrooms, and on each additional story and level of the dwelling. Smoke alarms shall be installed not less than 3 feet horizontally from a bathroom door or opening. Alarms may be solely battery operated in existing buildings where the alterations or repairs do not result in the removal of interior walls or ceiling finishes exposing the structure, unless there is an attic, crawl space or basement available which could provide access for building wiring without the removal of interior finishes. Where more than one smoke alarm is required to be installed, the alarms shall be interconnected in such a

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manner that the activation of one alarm will activate all of the alarms in the individual unit, except where alterations or repairs do not result in the removal of interior wall or ceiling finishes exposing the structure, unless there is an attic, crawl space or basement available which could provide access for interconnection without the removal of interior finishes. The alarm(s) shall be clearly audible in all bedrooms over background noise levels with all intervening doors closed. All smoke alarms must be installed in accordance with Section R314 of the California Residential Code (CRC).

Carbon monoxide alarms approved and listed by the State Marshall shall be installed in existing dwellings or sleeping units that have attached garages, fossil fuel-burning appliances or fireplaces as follows: outside each separate dwelling unit sleeping area in the immediate vicinity of bedrooms, on every level of dwelling unit including basements and in any bedroom where a fuel burning appliance is located within the bedroom or its attached bathroom. In existing dwelling units, a carbon monoxide alarm is permitted to be solely battery operated where repairs or alterations do not result in the removal of wall and ceiling finishes or there is no access by means of attic, basement or crawl space. Where more than one carbon monoxide alarm is required to be installed, the alarms shall be interconnected in a manner that activation of one alarm shall activate all of the alarms in the individual unit, except where repairs do not result in the removal of wall and ceiling finishes, there is no access by means of attic, basement or crawl space, and no previous method for interconnection existed. All carbon monoxide alarms must be installed in accordance with Section R315 of the California Residential Code (CRC).

Minimum access and emergency escape from every basement, habitable attic and sleeping room CA Residential Code (CRC) R310: Escape and rescue windows shall have a minimum net clear opening area of 5.7 square feet, except that escape windows located at grade level may be 5.0 sq. ft. The net clear opening height dimension shall be not less than 24 inches. The net clear opening width dimension shall be not less than 20 inches. New emergency escape and rescue openings shall have the bottom of the clear opening not more than 44 inches from the floor. Existing windows provided as a means of escape or rescue, shall comply with the finished sill height and the opening dimensions required by the code under which the window was installed (see Table 1 below). EXCEPTION: Pursuant to CRC R310.2.5 a replacement window is exempt from the maximum sill height and opening requirements if the window is the largest that will fit in the existing rough opening; and the replacement window is of the same operating style as the existing window that provides equal or greater window opening area than the existing window; and there is no change of occupancy associated with the building. This exception only applies to existing windows in one- and two-family dwellings.

Table 1

Code Under

Which the

Window was

Legally Installed

Minimum Net

Opening Size

Minimum

Opening

Dimensions

Height

(Maximum

From Floor)

Prior to 1964 6 Sq. Ft.

(Window Size Only)

None None

1964 to 1980 5 Sq. Ft.

(Net Opening)

22 Inches - Height

22 Inches - Width

48 Inches to Sill

1980 to 12/31/2007 5.7 Sq. Ft.

(Net Opening)

24 Inches - Height

20 Inches - Width

44 Inches to Sill

1/1/2008 to Present 5.7 Sq. Ft.

(Net Opening)

5.0 Sq. Ft. for grade-

level windows

24 Inches - Height

20 Inches - Width

44 Inches to

Clear Opening

24"

Min

.

Cle

ar

20" Min.

Clear

44"

Max.

To F

loor

5.7 Sq.

Ft.* Min.

Clear

Opening

Floor

* May be 5.0

sq. ft. minimum

clear opening if

located at

grade-floors.

Emergency escape &

rescue openings must meet

all listed dimensional

requirements.

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Prescriptive Energy Efficiency Requirements: Replacement and added windows and skylights (fenestration) shall comply with the California Energy Code. Replacement Fenestration/Glazing (See CA Energy Code Please complete either the CF-1R-ALT-Windows form (attached) or a form CF1R-ALT-05-E or a form CF1R-ALT-01-E (for alterations) or submit energy performance approach documentation.

• When 75 square feet or less of existing vertical fenestration (window) is replaced, the replacement vertical fenestration must have a maximum U-factor of 0.40 and a maximum Solar Heat Gain Coefficient (SHGC) of 0.35.

• When more than 75 square feet of existing vertical fenestration area is replaced, the new fenestration product must have a maximum U-factor of 0.30 and a maximum SHGC of 0.23.

• When an equal area of existing skylights is replaced the replacement skylights must meet a maximum 0.55 U-factor and a maximum 0.30 SHGC.

Added Fenestration/Glazing Please complete either the CF-1R-ALT-Windows form (attached) or form CF1R-ADD-01-E or form CF1R-ADD-02-E or submit energy performance approach documentation.

• No U-factor or SHGC requirements when 3 sq. ft. or less of glazing in doors or 3 sq. ft. or less of dual pane tubular skylight is added.

• When less than 75 square feet of vertical fenestration area is added:

o the new fenestration product must have a maximum U-factor of 0.30; and a maximum SHGC of 0.23.

• When more than 75 square feet of vertical fenestration area is added:

o the new fenestration product must have a maximum U-factor of 0.30; and a maximum SHGC of 0.23; and

o the total fenestration area of the home shall not exceed 20% of total conditioned floor area; and

o the total west facing fenestration area of the home shall not exceed 5% of total conditioned floor area;

or

o Submit Performance Approach energy calculations/documentation.

• When 16 square feet or less of skylight area is added, the new skylights must meet a maximum 0.55 U-factor and a maximum 0.30 SHGC.

• When more than 16 square feet of skylight area is added:

o the new skylight products must have a maximum U-factor of 0.30 and a maximum SHGC of 0.23; and

o the total fenestration area of the home shall not exceed 20% of total conditioned floor area; and

o the total west facing fenestration area of the home shall not exceed 5% of total conditioned floor area;

or

o Submit Performance Approach energy calculations/documentation.

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New fenestration products must be certified and bear a temporary label from the National Fenestration Rating Council (NFRC) specifying the rating. The label shall be present on the window during inspection. Al doors and windows between conditioned and unconditioned space must be weather-stripped and all joints and penetrations caulked and sealed to limit air leakage.

The repair or replacement of glass in an existing sash and frame or sashes in an existing frame are not required to meet any requirements of the energy efficiency standards.

2019 CA Energy Code

Prescriptive Certificate of Compliance: Residential (2019 CA Energy Code) CF-1R-ALT-WINDOWS

Page 1

Project Name: Climate Zone: 2 No. of Stories:

General Information

Projec Address: Enforcement Agency: City of Sonoma Date:

Building Type Single Family

Multi Family Conditioned Floor Area: Circle the Front Orientation: N, E, S, W. or degrees: _________

NOTE: This form is not to be used for Newly Constructed Buildings or Additions

FENESTRATION PROPOSED AREAS (includes doors with glazing, windows and skylights)

Replacing 75ft2 or less of fenestration area (excluding skylights) — Replacement windows shall have a maximum U-Factor of 0.40 and

a maximum SHGC Value of 0.35. (If this box is checked, complete Page 2 and submit form.)

Replacing more than 75ft2 of fenestration area (excluding skylights) — Replacement windows shall have a maximum U-Factor of 0.30

and a maximum SHGC Value of 0.23. (If this box is checked, complete Page 2 and submit form.)

Replacing existing skylights (equal or smaller area) – Replacement skylights shall have a maximum U-Factor of 0.55 and

a maximum SHGC Value of 0.30.

Adding 3ft2 or less of glazing in doors and/or skylight area (with dual pane diffuser) – No U-Factor or SHGC requirement.

Adding more than 3ft2 of glazing in doors - Newly installed doors with glazing shall have a max. U-Factor of 0.20

Adding 75ft2 or less of fenestration area - Newly installed windows shall have a max. U-Factor of 0.30 and max. SHGC Value of 0.23.

Adding more than 75ft2 of fenestration area — Newly installed windows shall have a max. U-Factor of 0.30 and max.

SHGC Value of 0.23 and must meet the ALLOWED ADDED FENESTRATION AREA requirements below.

Adding 16ft2 or less of skylight area – Newly installed skylights shall have a max. U-Factor of 0.55 and a maximum SHGC Value of 0.30.

Adding more than 16ft2 of skylight area – When adding more than 16 square feet of skylight area, skylights shall have a max. U-Factor of

0.30 and max. SHGC Value of 0.23 and must meet the ALLOWED ADDED FENESTRATION AREA requirements below.

Proposed ADDED Fenestration Type and Frame

(Windows, Glass Doors or Skylights)

Orientation

(North, East,

South, West,

Skylight)

Proposed ADDED

Fenestration Area1

(ft2)

Maximum

U-factor2

Maximum

SHGC2

1. Fenestration area is the area of total glazed product (i.e. glass plus frame). Exception: When a door is less than 50% glass, the fenestration area

may be the glass area plus a “2 inch frame ” around the glass.

2. Actual fenestration products installed must be documented on CF2R forms and shall be equivalent to or have a lower U-factor and/or a lower

SHGC value than that specified on this form.

ALLOWED ADDED FENESTRATION AREA (Complete if more than 75ft2 of vertical fenestration or 16 ft2 of skylight area is added)

A B C D E F G

CFA of Entire

Dwelling7

Allowed

% of

CFA2,3

Existing

Fenestration

Area4

Area

Removed5

Fenestration

Area Added6

Allowed Area

(A x B)

Proposed Area1,4

(E-D) + C

Total Fenestration Area2’(ft2) 20% >

West Fenestration Area1’3 5% >

1. The Proposed West Fenestration Area includes West-sloping skylight area and any other skylight area with a pitch less than 1:12.

2. Includes all proposed or installed West orientation fenestration and all skylights.

3. No more than 5% of the CFA is allowed for west-facing glazing in Climate Zone 2.

4. Existing Fenestration area must be counted toward the maximum allowed 20% of the whole building and calculated in Column G. The

Proposed Area must be less than or equal to Column F.

5. Enter the fenestration removed as part of the alteration if any in column D.

6. Enter the Fenestration area that is being added as part of the alteration.

7. CFA means Conditioned Floor Area

Prescriptive Certificate of Compliance: Residential (2019 CA Energy Code) CF-1R-ALT-WINDOWS

2019 CA Energy Code

Mandatory Requirements for Fenestration Products and Exterior Doors: §110.6(a)l: Doors and windows between conditioned and unconditioned spaces are manufactured to limit air leakage.

§110.6(a)2: The fenestration product's U-factor shall be rated in accordance with NFRC 100, or use the applicable default U-factor set forth in Table

110.6-A (see exceptions in the Energy Code).

§110.6(a)3: The fenestration product's SHGC shall be rated in accordance with NFRC 200, or use the applicable default SHGC set forth in Table

110.6-B. (see exceptions in the Energy Code)

§110.6(a)4: The fenestration product's visual transmittance (VT) shall be rated in accordance with NFRC 200 or ASTM E 972. For tubular skylights

VT shall be rated using NFRC 203.

§110.6(a)5: Fenestration products (except field-fabricated windows) have a label listing the certified U-Factor, certified Solar Heat Gain Coefficient

(SHGC), and infiltration that meets the requirements of §10-111(a)1.

§110.6(b): Exterior doors and windows are weather-stripped; all joints and penetrations are caulked and sealed.

Both the Documentation Author and the Responsible Designer must complete and sign below.

Residential Alterations Climate Zone 2 Page 2

Project Address:

Documentation Author’s Declaration Statement

• I certify that this Certificate of Compliance documentation is accurate and complete.

Name: Signature:

Company: Date:

Address: Phone:

City/State/Zip: E-Mail:

Responsible Designer’s Declaration Statement

• I am eligible under Division 3 of the California Business and Professions Code to accept responsibility for the building design identified on

this Certificate of Compliance.

• I certify that the energy features and performance specifications for the building design identified oil this Certificate of Compliance conform

to the requirements of Title 24, Parts 1 and 6 of the California Code of Regulations.

• The building design features identified on this Certificate of Compliance are consistent with the information provided to document this

building design on the other applicable compliance forms, worksheets, calculations, plans and specifications submitted to the enforcement

agency for approval with tins building permit application.

Name: Signature:

Company: Date:

Address: License:

City/State/Zip: Phone: