HOME ENERGY SOLUTIONS

Weatherization Specification Manual

WINDOWS AND PATIO DOORS

WI 1.0—Introduction

Window requirements shall apply to patio doors unless otherwise stated. Windows shall be installed and supported according to the manufacturers’ specifications. If window weight cavities exist and there is access, the weights shall be removed and the cavity shall be filled with insulation.

Overview for all glazing systems:

• Safety glazing shall be used where required by current state code. See sections on safety glass for details.
• Windows shall operate smoothly and safely.
• Screens shall be furnished with all operable windows.
• Exposed wood, including frame, sash, trim, stops, and sills, shall be, at a minimum, sealed and primed.
• Hardware and fasteners shall be aluminum, stainless steel, or other noncorrosive materials.

Window incentives shall be paid only for windows of the same area as original windows except when window area must be increased to meet egress requirement.

WI 1.1—General Requirements for Glazing  

Replacement windows shall be certified and labeled for U-factor in accordance with the simulation, testing, and certification procedures of the National Fenestration Rating Council Incorporated (NFRC).

Windows shall meet one of the following standards:

• Single family homes: U-factor of 0.30 or better
• Multifamily buildings:
  • For basic incentive level: U-factor of 0.32
  • For increased incentive level: U-factor of 0.30

U-factors shall be verified in one of the following methods:

• NFRC labels shall be left on the windows until the time of the inspection.
• NFRC labels shall be left at the job site and be readily available at the time of the inspection for each style of window. The labels shall be legible and left in an orderly manner. For example, the labels may be pasted in a notebook. The labels will be collected by Home Energy Solutions inspector.
• Home Energy Solutions will be supplied with manufacturer’s shipping order or invoice for the windows, including:
  • Name of customer
  • Model number of windows
  • U-factor of windows
  • Number and size of windows installed

Illustration WI1.1

The following window types are common retrofits. For windows not meeting these descriptions, contact Home Energy Solutions for information on incentive compliance.

WI 1.2—Block Windows

Block windows do not have nailing flanges. Block windows shall be secured to the rough opening within four inches of each side corner and a minimum 12 inches on center thereafter. Block windows shall not be smaller than the interior jamb and shall fit tightly with it. Gaps of over 3/8 inch between the exterior siding and the block window shall be trimmed. Exterior or interior voids over 3/8 inch in depth or width shall be filled with backer rod prior to caulking. Exposed block windows shall be flashed. (See the "Exposed to the Elements" diagram that follows.)

Illustration WI 1.2

The flashing shall tuck up behind the exterior siding at least 1 inch. Flashing shall have a downward bending lip of at least ¼ inch on the front and ends. Block windows shall be supported at the “fin line.”

WI 1.3—Surface-Mounted Windows

Home Energy Solutions does not allow surface-mounted windows on site-built houses or on manufactured homes with wood siding. This section does not apply to stucco-mounted windows. Surface-mounted windows designed for this purpose may be installed on manufactured homes with aluminum siding.

WI 1.4—Cut-Out Windows

Cut-out windows have nailing flanges and are installed on the sheathing or framing. The tops of cutout windows shall be flashed over the filler or trim piece with metal flashing, unless the tops of the windows are protected by an overhang (See the “Exposed to the Elements” diagram that follows).

The sides of cut-out windows shall be flashed with 15-pound felt or an equivalent building paper. The building paper shall be inserted underneath the existing siding and building paper and over the fins of the windows. The bottoms of cut-out windows shall be flashed with 15-pound felt or an equivalent building paper. The building paper shall be inserted underneath the existing siding and over existing building paper and under the bottom fins of the windows.

All filler and trim pieces must be thoroughly caulked.

WI 1.5—Stucco-Mounted Windows

Stucco-mounted windows are replacement windows that mount directly to the frames of existing windows.

Illustration WI 1.5

The fin of the new window and the outer flange of the existing window shall be sealed with a sealant designed for this purpose. The sealant must stick to both the vinyl fin and the aluminum flange. The lip of the existing aluminum flange shall be at least 3/8 inch wide. If "Exposed to the Elements," the top seam shall be "flashed" with a properly installed drip cap.

The replacement window shall be secured with a minimum of two rustproof screws on each side. These screws shall be spaced no more than 24 inches on center, and be no more than 4 inches from each corner. Further, the screws shall be inserted through the replacement window frame into the studs of the window opening in a manner similar to the one used when installing a block window.

The gap between the frame of the replacement window and the interior trim shall be caulked. If the gap exceeds 1/4 inch, the gap shall be filled with closed cell backer rod, or chinked and caulked, and then the gap shall be covered with quarter-round molding or similar. The molding shall then be caulked on both the top and bottom seams.

The bottom rail of the existing window shall be cleaned to free up weep holes. The miter joints on the fin of the replacement window shall be smooth so the corners do not bulge from the aluminum window.

WI 1.6—Exposed to the Elements

To determine if a window is "Exposed to the Elements" use the "Two-to-One Ratio" system. See the following illustration:

Illustration WI 1.6

WI 1.7—Miscellaneous Requirements

The bottom rail of a patio door shall be firmly supported within 1/2 inch of exterior edge of the frame. Any wood that touches the ground or cement must be pressure-treated.

WI 1.8—Health and Safety Requirements

All windows shall meet the following egress and safety glazing specifications. If state or local code becomes more restrictive than Home Energy Solutions specifications, then installers shall be required to meet current state or local code.

WI 1.9—General Safety Glazing Requirements

Safety glazing requirements shall apply to replacement windows and patio doors, multi-glazing inserts, and storm windows.

When measuring glazing to decide whether it needs to be safety glazing, measure only the glass itself. Do not measure the sash. All safety glazing shall conform to the Safety Glazing Certification Council (SGCC) labeling requirements.

Each lite requiring safety glazing shall bear the manufacturer's permanent safety glazing label. This label of identification shall be etched or ceramic-fired on the glazing and be clearly visible in one of the corners of the lite.

WI 1.10—Hazardous Locations Requiring Safety Glazing

The following shall be considered specific hazardous locations for the purpose of glazing:

1. Glazing in entry doors.
2. Glazing in patio doors and French doors.
3. Glazing in storm doors.
4. Glazing in a fixed or operable panel that meets all of the following conditions:
   1. The exposed area of an individual pane is greater than 9 square feet.
   2. The bottom edge is less than 18 inches above the floor.
   3. The top edge is greater than 36 inches above the floor.
   4. One or more walking surfaces are within 36 inches horizontally of the glazing.

In lieu of installing safety glazing in situation number 4, a protective bar may be installed on the accessible side(s) of the glazing 34 to 38 inches above the floor. The bar shall be capable of withstanding a horizontal load of 50 pounds per lineal foot without contacting the glass and be a minimum of 1-1/2 inches in height.

Illustration WI 1.10A

5. Glazing in hot tubs, whirlpools, saunas, steam rooms, bathtubs, and showers where the bottom edge of the glazing is less than 60 inches above the drain inlet.

Illustration WI 1.10B

Glazing in a fixed or operable panel adjacent to a door where the nearest vertical edge is within a 24-inch arc of the door in a closed position and whose bottom edge is less than 60 inches above the floor or walking surface.

Illustration WI 1.10C

Illustration WI 1.10D

WI 1.11—Miscellaneous Safety Glazing Requirements

Any glazing panel that can be moved into a hazardous area (e.g. the operable panel of a horizontal sliding window) shall also be made of safety glazing. However, any glazing panel that cannot be moved into a hazardous area (e.g. the upper panel of a single-hung window) does not need to be made of safety glazing.

Fixed glazing panels contained in one window surround, but separated by structural mullions, do not need to be safety glass if they are not located in a hazardous area.

Safety glazing will not be required in the following instances:

1. Openings and doors through which a 3-inch sphere is unable to pass.
2. Leaded glass panels.
3. Faceted and decorative glass.

WI 1.12—Emergency Egress Openings

Every sleeping room shall have at least one operable window or exterior door approved for emergency egress or rescue. The units shall be operable from the inside to a full, clear opening without the use of separate tools. Where windows are provided as a means of egress or rescue, they shall have a sill height of not more than 44 inches above the floor.

All egress or rescue windows in sleeping rooms shall have a minimum net clear opening of 5.7 square feet. The minimum net clear opening height dimension shall be 24 inches. The minimum net clear opening width dimension shall be 20 inches. Windows where the bottom edge is level with the ground may have a minimum net clear opening of 5 square feet.

When a window not complying with emergency exit provisions is replaced with an energy-efficient window, the existing window may be replaced if the replacement window has the same frame opening dimensions and same emergency exit opening as the old window. If a replacement window has the same frame opening dimensions but a smaller emergency exit opening than the old window, it shall not be replaced unless the smaller exit opening still meets the current emergency exit opening requirements.