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How to build a wooden window well

Want to know how to build a window well?  Not just build a window well, but build a window well well?  Well, we’ll show you here. (Sorry.  I realize that was a lot of set up for a fairly uninteresting word joke.   It is late.  Also, I’m never quite sure if anybody reads this thing, so I have to be primarily concerned with entertaining myself.)

Keep in mind, most people aren’t adding window wells to existing basements, but to new construction homes.  Of course, you might be renovating your basement and replacing an old window well.  But if you were to add a new window to a basement below grade, you’d have to start with drainage, which would mean excavating quite a bit more that just the area of the window well itself.  You’d have to put in the pipes something like this:

Notice the pipes on the right side of the photo, the ones that turn upward?  Those will be for the drainage for the window well.

Important: remember the BC Building Code 2006:  Windows must be large enough for a grown man to escape from in the event of a fire–and that goes for the window wells, too.  This means that if you are replacing your existing window and/or window well, you have to bring it up to code, which may require putting in a larger window.  In addition, you can’t have a transom window that opens out, because this prevents escape in the event of a fire.  The only exception to this, as far as I know, is a bathroom.  The BC Building Code is based on the assumption that when you are in trouble with your wife you are sleeping on the couch, not the tub.

Next, you have to backfill with earth to just below the pipes, and put gravel in.  That will help water find its way to the drain.

Next, lay out your measurements.  Code says the window well bottom has to be 6 inches below the window itself, and 4 inches from each side.  It also has to be a minimum of 24 inches out from the window.  Measure that out, draw a line in pencil.  now add to that the thickness of the wood, and draw another line.  We’re using 4×6 pressure-treated lumber.  Using a concrete drill, make pilot holes into the concrete and install concrete screws with bolt ends; fix one piece of your wood vertically with nuts and washers over the screw ends to provide a brace for the window well to attach to.

Now we’re ready to put in the window well itself.  Butt the ends up to the foundation, and using galvanized nails or screws for PT lumber, attach the horizontal pieces to the braces, like so:

Make sure that as you are laying it out, you measure your cuts so as to allow you to stagger the corners for maximum strength:

Towards the end, you can save yourself a few cuts by just letting the ends stick out.  Remember, it will all be buried anyway.

Build your window well up to just higher than your finished grade will be.

Now you’re ready for backfill.

Voila!  Finished Window Well!  Aren’t you clever?  Keep in mind, depending on the depth of your window well, the BC Building Code 2006 may require you to put a hinged cover or screen over the window well to prevent people from accidentally falling into the well while still allowing escape in an emergency.  When I get some, I’ll show them to you.

What does all this cost?  approximately $250 per window well, materials and labour.  Most builders do not use metal window wells anymore, as they have to be custom made to make sure that they are appropriate for the code opening clearances, and they take time to order.  Wood can be done today.

I was surprised, however, to learn that metal window wells are significantly cheaper than wood.  My window well would have cost me only $60 for the metal, plus the labour to install, which would only be the screws into the concrete, and then backfill.  Still, cost isn’t everything, and if builders making spec homes for resale are using wood, there’s probably a good reason.

Having said that, if you want to see a similar process with a galvanized metal window well, take a look at this post from Barry’s blog, Life in Quotations.

Bye for now!


  1. M Rachel Munoz says:


    Thanks for your detailed post. People really are reading these! I have been trying to figure out how to do this for a while now and this was the first post I could clearly understand. I have a daylight basement apartment that needed an upgrade. Digging the well cutting the concrete and installing the window all seemed easy compared to figuring out what to do with the giant hole. It is late Sept. in Alaska I have no more time to procrastinate. Thanks for the instructions I’m making my materials list now.

    Happy building,


    • admin says:

      I’m glad to help. My feeling throughout the building is that if there is something that I didn’t know about before, chances are someone else could be saved a headache if I share what I’ve learned. Good luck with your project!

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