Introduction: Dual Duty Doggie Door

If you have a dog, chances are you let him/her in and out more than you really want to.
Why not give your dog a little more self actualization?

I did not want to cut a hole in my nice metal door to install a commercial "doggie door", so instead I leveraged a feature of my existing porch door - a slider window in the lower portion.

After a few years of experimenting with self adhesive and magnet hooks, I finally screwed hooks right into the door - with much more satisfactory results.

I now have a doggie door that does duty in summer (with only the exterior flap in place), and also in winter (with the interior flap in place, as well). Additionally, it can be completely closed when your dog is on vacation, or it's -40 with a howling wind, (it happens...).

Step 1: Organize Your Project


  • Hammer & centre punch (or a nail);
  • Drill & bits;
  • Hand saw;
  • Sewing machine (& needles, thread, etc.);
  • Level and tape measure.


  • Heavy waxed canvas (1 pieces of ~28" x 36" - e.g. from a defunct old tent, repurposed) for the outside flap;
  • Not quite so heavy unwaxed canvas (1 pieces of ~28" x 36") for the inner flap;
  • Heavy cord (4 pieces of ~18" each);
  • Cup hooks (brass or stainless steel, 4 of them) (sized 3/4" or 1");
  • Light wooden stakes (2 of them) (e.g. 1" x 1/2" x ~29");
  • Light galvanized chain (1 or 2 pieces ~24").

Step 2: Indoor Work - Preparing for Installation

I hemmed each piece of canvas so they were each about 6" wider than the 21" opening in the sliding window portion of the door.

I then sewed a 2" pocket along the top edge of each to accommodate the wooden stake, and also a 2" pocket along the bottom to take the chain (though I ended up putting chain along the bottom edge of only the outdoor flap).

I cut the stakes so they were about 8" wider than the sliding window portion of the door and drilled holes for the cords.

Step 3: Outdoor Work - Installation

Use the centre punch (or a nail) to mark the door where you want to screw in each cup hook.

Drill a SMALL pilot hole, then screw in a cup hook. Continue for the rest, using a level and tape measure to ensure they are at the same height.

I did this about 5" above the top of the opening when the slider is at its maximum height, about 1" outside the edge of the moulding around the glass. The higher the hooks are, the easier it will be for the dog to move the flap, but also easier for the wind to catch it...

Our dog is small enough the slider does not need to totally up, so it reduces the amount of cold air (&/or mosquitoes) coming in. When a big dog comes to visit, the opening is easily enlarged.

Step 4: Test and Tweak

Your dog will easily figure out how this new fangled thing works - a doggie treat or two works wonders.

Test the slider with the flaps in place, so there won't be any unpleasant surprises when you decide to close it in the middle of a howling winter blizzard.

Optional enhancement: I cut a piece of blue, rigid styrofoam insulation to reduce drafty airflow between the top of the outer flap and the frame of the slider. In the winter I wedge it into the grooves of the opening, just under the slider. Also, I covered it with duct tape to slow the weathering (UV) damage and it has lasted several years.

So there you go - give yourself a pat on the back, and your dog a pat on the head!