How do I install an Egress Window?

This Installation Guideline is intended to give the installer a general overview on how to correctly install a Basement Egress Window. This installation guideline is not intended to replace the manufacturer’s installation instructions, but to supplement and expand on them. An installer must follow the manufacturer’s installation instructions whenever they vary from these guidelines to keep the Manufacturer’s Warranty in force.


  1. It is the responsibility of the owner, architect, contractor and or builder to select products that comply with applicable, state and local building codes and is appropriate for the application or use. A building permit may be needed.
  2. REDDCO Inc. is not responsible for claims resulting from the failure of the contractor or homeowner to properly install or maintain the Egress Window, Window Well, and Cover.
  3. Call your local diggers hotline before beginning excavation to avoid accidental contact with underground utility lines
  4. Gutters, Down Spouts, Faucets on exterior walls, Sprinkler Heads and Sump Pump Outlets should be at least 6 to 10 feet away from the window well. All water must be directed away from the well to assure proper drainage.

Step 1: Select an Egress Window location

  1. Select a location without or remove, wires, pipes or other utilizes.
  2. East or south wall locations allow for maximum light.
  3. Installing a window in the same location as an existing small basement window is popular.

Step 2: Purchase an Egress Window

  1. Make sure the window selected meets your current state or local residential egress code. See “What is the International Residential Code” and “What is an egress window?”
  2. See for a large selection of Egress Windows and Wells

Step 3: Mark the Egress Window’s location

  1. How to install an egress windowUse a grease pencil to layout the cutting location of the window on the inside of the basement wall.
  2. Make sure to account for any framing you intend to use plus 1?4” all around to allow room to slide the window into place this is called the windows rough opening.
  3. Remember the inside sill of the window can’t be more than 44”off the floor to meet code, It good to target 42” or less.

Step 4: Transfer the center line of the windows rough opening location to the outside wall

  1. How to install an egress window 2How to install an egress window 3It is a good idea to build a small temporary frame that gets coved in plastic on the inside of the basement at this time to keep the dust caused by the drilling and wall cutting contained at this time.
  2. Using a 1?2” diameter x 12” to 16” long masonry drill bit, drill a hole through the wall on the centerline of both the top and bottom of the horizontal cutting locations marked on the wall in step 3-a.

Step 5: Dig the hole

  1. How to install an egress window 4Using the holes drilled through the wall in step as your center line dig a hole large enough to accommodate the Basement Egress Well so it is center around the planned egress window opening.
  2. Dig a hole 4 foot wider at the foundation wall, 1 foot wider than the well the rest of the way around, and approximately 19 ” deeper than the bottom of the Window being installed.
  3. Clean any excess dirt off the outside foundation wall with a brush.

Step 6: Cut the window’s rough opening into the foundation wall

Note: A lentil should be installed if; 1) the ceiling joists are running perpendicular to the wall the window is being installed into; 2) a window is being put into a Block Wall; 3) a 48” wide or greater Sliding Egress Window is being installed.

  1. How to install an egress window 5Mark the rough opening of the Egress Window on to the outside of the foundation wall with a grease pencil using the two holes drilled through the wall as the centerline of the vertical window opening and the top and bottom of the horizontal opening with the help of a long level…
  2. Cut the rough window opening with a Diamond Blade Concrete Demolition Saw, starting on the outside of the foundation wall. A concrete saw is an unwieldy tool that creates a large cloud of dust, so go slow, wear full eye protection (goggles) and a tight-fitting dust mask. If a water-cooled demolition saw is available it will greatly reduce the mess.
  3. In a poured concrete wall make the first pass 1?4 inch deep, in concrete block a 1-inch deep first pass can be made. Once a path is established for the saw blade you can start making deeper cuts. The last cut should be at least 3 inches or half the wall thickness deep.When finished outside repeat cutting process on the inside foundation wall.
  4. Expect dust to be a problem, use the temporary plastic covered frame inside
    the basement to help contain the dust. If cutting a Block Wall move to step 6-e. or if cutting poured concrete proceed to step-f.
  5. How to install an egress window 10After cutting a Block Wall on all sides start tapping the upper blocks with a 3-pound hammer until they either break loose whole or crumble into pieces. Clean up the rough opening by chiseling away any obstructing mortar. Go to Step 7:
  6. After cutting the Poured Concrete Wall on all sides break-out the rough opening with a 3-pound hammer, clean up the cut surfaces if necessary using a cold chisel and 3-pound hammer.
  7. If you plan to install a frame into the rough opening of the poured concrete wall proceed to step 7 or if you don’t plan to install a frame which is not necessary for a poured concrete wall Go to Step 8:

Step 7: Concrete Block Wall – Installing a Pressure-treated Wood Frame

  1. How to install an egress window 6A frame is required to properly install an Egress Window into a Block Wall as the hollow block is not a good anchor for an egress window.
  2. Use pressure treated wood or a synthetic composite material like Azek® or Trex® to build a frame to fit the rough opening.
  3. Make sure the frame is square before installing.
  4. Apply construction adhesive to all surfaces of the frame that will contact the block wall.
  5. Place the Wood Frame into the rough opening so that the outer edge of the Frame is flush with the outside of the Block Wall.
  6. Nail the bottom of the Frame to the (bottom of rough opening), then nail the sides and top of Frame with 2 1/2 inch harden concrete nails or a power driving tool. Note: Drive the nails into the mortar joints, not the concrete blocks to avoid cracking the hollow blocks.

Step 8: Install the Egress Window

  1. Begin the new window installation by test-fitting the Egress Window into the opening, resting the window on the sill; aligning it squarely with the opening, and then tip it forward into place.
  2. If it fits properly move to step 8-c, if not adjust the opening then move to step 8-c.
  3. Use tapered wood shims to level and plumb the window in the rough opening. Note: Make sure the Egress Window remains square as you shim; too tight a fit will keep the window from moving freely later. If installing a Hinged In-swing Window be to make sure to insert shims directly under the hinged area to allow for proper window support when the sash is hinged open. If installing in a Concrete Block Wall go to step 8-c; if installing in a Poured Concrete Wall go to step8-d.NOTE: Do not put any fasteners through the bottom sill of the window frame as this will cause the window to leak.
  4. Concrete Block Wall – Once the window is square and plumb, fasten window into a pressure-treated wood frame with 1 1?2 inch long galvanized or stainless steel screws driven through the tapered wood shims.NOTE: Pilot holes should be predrilled through the vinyl window frame and, shims to prevent cracking of the vinyl frame or shims when installing screws. Move to step 8-f.
  5. How to install an egress window 7Poured Concrete Wall – Use 1 1?2 – 2-inch long Concrete Anchor’s for a Poured Concrete Wall, also driven through the tapered shims.NOTE: Pilot holes should be predrilled through the vinyl window frame, shims and into the Poured Concrete Wall to prevent cracking of the vinyl frame and shims, prior to installation of the Concrete Anchors.NOTE: Make sure you don’t caulk the windows weep holes closed!!
  6. How to install an egress window 8Make sure the window moves free and smooth.
  7. Seal the gap between the window and the rough opening by filling with either round pipe insulation or a low-density expandable urethane foam spray.
  8. Trim the window interior and exterior as desired.
  9. Use a Butyl Caulk or a low-temperature Silicon Caulk on the exterior when trimming out the window.


NOTE: Make sure you don’t caulk the windows weep holes closed!!

How to install an egress window 9


Step 9: Install the Egress Well and Cover

  1. See “How do I install an Egress Well?” for detail installation instructions.

Authored By: Steven Forman at REDDCO Inc.,, 1/2/2018