How to Insulate a Basement (Egress) Window
- Vicki Liston
- Sep 29, 2022
- 3 min read
Basement egress windows provide a means of getting out during emergencies and letting in the natural light. They also let in chilly drafts and crawly bugs!
A Removeable Egress Window Insert will keep the drafts and bugs at bay, won’t inhibit the functionality of the window, AND if desired, even add some privacy without blocking the light.
Do your material shopping on Amazon HERE! Proceeds earned at this affiliate link (at no cost to you!) are donated to no-kill animal shelters and rescue organizations ❤
You'll need:
2x2s and 2 and half inch screws
Miter saw, safety glasses, measuring tape, drill and bits for screws and pilot holes, a sanding block or sand paper, scissors,
Thick plastic drop cloth or plastic sheeting and a hot glue gun.
Spray paint and a drop cloth – this is optional. If you plan on leaving your insert clear, you may want to paint the wood.
Two handles and extra long screws that will accommodate the 2x2s width.
Weather stripping – I’m using heavy-duty, half inch wide by 5/16ths inches thick strips.
If you don’t want your finished insert to be clear, you’ll want additional items for creating an opaque look. I’m using some extra frosted window cling.
First, measure the egress window. Mine measures 35 inches by 22 and 5/8s inches.
Subtract a half inch from the long sides and use a miter saw to cut two 2x2s to that measurement (I'm using my window's measurements as an example. Just plug in your own measurements -long side, short side, and 2x2 width - into the equations to get the cut lengths you need).
Next, measure the width of your 2x2. Most are about 1 and a half inches thick but measure for a more exact number. Mine is 1 and 3/8th inches thick.
Double that number...
and subtract it from your short sides’ measurement. So 22 and 5/8s minus 2 and 3/4s is 19 and 7/8.
Subtract another half inch to get 19 and 3/8ths. Cut two 2x2s to that measurement.
Use the sanding block or sand paper to sand each piece of wood smooth. It’s nice to have some help with this step (I clearly don't...).
Place the two shorter pieces in between the ends of the two longer pieces.
Drill four pilot holes so the wood doesn’t split...
...and then drive a screw in to secure. Do this for all four corners.
If you want your insert to remain clear and you’re not concerned about privacy, you can spray paint the frame over a drop cloth. Allow to fully dry before continuing.
Drill holes for the handles but don’t add the handles just yet.
Place the plastic sheeting or thick drop cloth over the frame and run a line of glue along the top edge.
Wait a moment for the glue to cool a bit and then press the plastic down.
Pull the plastic taut but not too tight – you don’t want it to be too loose but you also don’t want the plastic to rip. Glue down the two shorter sides.
Flip the frame and pull the plastic taut again and glue down back at the top to complete a layer on both sides of the frame.
Trim the plastic a bit and glue the sides’ second layer.
Trim again if needed to get the excess plastic off of all sides of the frame. It’s ok if it isn’t perfect – the sides won’t be showing anyway.
The double layer of plastic creates a pocket of air inside which insulates the window.
Gently poke the screws through the holes to attach the handles.
If you want a clear insert, you can skip this step. But if you’d like it to be opaque, you can glue down frosted window cling or decoupage tissue paper, lace, or other kinds of materials to obscure the view.
Run the weather stripping along two sides of the frame – a short side and a long side.
The weather stripping is flexible so it will allow you to really squeeze the frame into the window opening.
Place the insert into the window opening…
And work into place.
It should fit very, very snug. If you have any gaps, you can add weather stripping on the remaining sides.
No more drafts or bugs and I can still use the ledge.
Watch the step-by-step video tutorial below. Proceeds from this video and the entire channel are also donated to no-kill animal shelters and rescue organizations. Watch, like, share, and subscribe to help raise monthly donations ❤
Insulating a basement egress window is a smart way to keep drafts and pests out while maintaining functionality. Using a removable insert allows for privacy and insulation without blocking natural light, making it an ideal solution. Whether you're looking for DIY options or professional help, windows installation experts can assist with creating an airtight seal that ensures comfort and safety. For more permanent solutions, consider window replacement services to enhance energy efficiency and ensure your egress window works seamlessly during emergencies.