Our last provincial election was, as they say, for the birds. It also left behind a bunch of election signs, so I figured some of them could be for the birds as well.

Supplies

Materials:

election sign
string
twist ties or zip ties or adhesive tape

Tools:

craft knife, utility knife or break-off blade knife
straight edge, or anything with a straight edge that you either can't or aren't worried about cutting into
darning or other large sewing needle

Step 1: Think About Your Design

Measure out your election sign. Think of how your bird house will fit together and how you want to hang it up. Also think about how you will open it to clean it out. The bottom should not be a water tight fit so it can drain if water gets in somehow. Also think about your material. Election signs in our area are made of Coroplast. It has reinforcing ribs that form flutes. This means it is anisotropic, it doesn't act the same in all directions.For your design it means you want to make any sharp bends or rolls parallel to the direction of the flutes.

The sign may have graphical features you want to have some fun with. Can you tweak the layout so the hole is somewhere funny?

Pick the size of the bird hole. Your best bet is to find a local reference since different birds live in different places. I found this reference from a wildlife place in my province.

Step 2: Layout on the Sign

My sign was 16" by 24". I decided my bird house would be hung with a string by the body so the
roof can slide up and down the string to clean it out. The bottom would be held in with tabs into the sides. This means only one corner has to be taped or held together otherwise. Here is a plan of how I laid out mine.

Think about how you will best transfer this to your sign. You could print it, tape it to the coroplast and cut right through the template.

If that's not an option, here are some layout steps that should work:

measure the 6" from the bottom and draw a line across
divide the area under the line into 4x6" squares
find the tip of the roof:
option1: find the center of the two squares that will be gable ends, and measure up the height of the roof from there
option 2: use dividers, set them to the length of the roof slope, draw a partial circle around the corners of the walls to find the tip of the roof
draw the slopes of the roof from the corners of the wall
find the center of the wall between the two roof slopes and draw a vertical line up from there (this will let you use up the max of the material)
Slide your square up that line until you have 5.25" to the roof slope, then draw a horizontal line to the roof slope
draw up vertical lines from the the intersection of the lines in (6) to the top of the material
draw the bottom for the bird house into the top left corner. It will be a square that is the size of the bottom. Then draw another square inside it that is (thickness of your material) smaller on all sides. Then draw in the tabs kind of like on the sketch, this is not precision work.
Mark a line about 1/4" up from the bottom of the walls, and another a bit more than (thickness of the material) up from that line; this will be the slot that the tabs for the bottom fit in.

Have a good look at what you drew and do a "sanity check" - does every edge look like it should fit together that way? If so, cut it out.

If you are making several bird houses you could use the first as a cutting template for the others.

Election signs for the birds.pdf
Download

Step 3: Cutting the Parts

To make sure your cuts are nice and straight, use a straight edge, or metal ruler, or anything straight that you are not worried about cutting into to guide your blade. Keep in mind the anisotropic structure of the coroplast while cutting it. If you are cutting diagonal, each time you cross a rib it will try to deflect your cut. To prevent your cut from being deflected, chose your direction of cut and place your straight edge so the ribs point to the straight edge in the direction of your cut.

To make sure you don't cut too far at corners, you can make each cut in two parts, always starting at the corner and cutting to the middle.

If you want your bird house to look finished from the outside, you will need to cut through the material in most places and only cut part way through in others, like the slots for the floor. You could try to only extend your blade a little bit from your exacto knife to make sure you don't cut too deep.

Slice out the top layer of any slots. For the corner ones, bend the material backwards on itself so the "lid" of the top stands out and you can slice it off. For the other slots, run the blade under and almost parallel to the surface and slice it off. Then flatten the ribs in the slots by running a hard edge over them. That's a lot easier than trying to cut them away.

Step 4: Punch Holes

Sorry, didn't get a picture for this.

If you will use twist ties or zip ties to close the corner on the walls, poke holes for them in both ends of the side walls before assembling them. If you are using tape, well, don't.

Poke holes as per the cutting template where the roof string will need to go - it's a lot easier to do before you start assembling.

Step 5: Assembling Walls and Floor

Fold the side walls into their shape and put the floor tabs into the slots in the wall. This is easier to do with a second person. Then secure the corner together, either with ties or with tape.

Step 6: Attach the Roof

A single piece of string will run so that loops of it hold down the roof and the house can hang from it.

start the string from the inside of a wall
pull it to the ouside of the wall, and then back inside on the other hole on that wall
feed the string from the underside of the roof to the top of the roof and then back down to the underside of the roof
feed the string through one hole on the inside of the other wall and back in from the outside of that wall
pull enough string to the loops on the outside of the walls so you will be able to pull if through the slits on the roof piece

Put the roof in place and pull the string tight. If the holes and slots in the roof are fairly tight you may need to tug the string separately on every loop to get it into place.

My first edition had the string come out the center of gable of the roof, but then the bird house spins in the wind. So, on later editions the string comes out through two holes about 4in apart along the gable of the roof.

Step 7: Hang Your Bird House Up Outside

Look at your local documentation you used to decide on the hole size and see if there are recommendations where your bird house should go. Just because it has a string coming out of the top doesn't mean that hanging it by that will end up the best way to place it - one of mine is tied with a string over the roof instead.

The bird houses on my picture are almost certainly too close together, I just had them there to show them off. Birds are competitive and may wreck each others brood when they are in each others' space.

Also make sure the placement of the bird house would not make it it easily accessible to predators like cats and even squirrels.