How to evacuate the hot air of a mobile air conditioning in the attic? You must use a roof window caulking kit (Velux) which is neither aesthetic nor practical to install.

I present my installation to you: a hatch with plug is installed in the wall, a 2m pipe crosses the lost part of the attic, and the hot air is evacuated outside the house by a grille.

I can turn the air conditioning on with the window closed and when I don't need it, I just have to put the plug back on the wall.

Supplies

Step 1: Before

First of all, we agree that mobile air conditioning is not the best solution, especially for the environment!

Not having the means to have a better insulated house, it is an acceptable solution because the heatwaves do not last very long in the north of France.

As soon as I bought an air conditioner, I found myself faced with the problem of the hot air exhaust pipe. So I tried caulking the window with some fabric to prevent hot air from entering. But it was neither practical nor very effective.

Step 2: Holes !

Inside, I drilled the 130mm hole in the plasterboard wall with a wide-toothed saw.

On the outside, I cut out a cardboard template and traced the circle in white pencil. Then I drilled a pilot hole to pass the blade of the jigsaw.

Once the insulation was pushed back (glass wool) I saw the outside light.

Step 3: Pipe Passage

I used a wooden cleat to guide the flexible pipe.

Step 4: Grid and Cap

Inside, I fixed the cap to the pipe with aluminum tape. Then I screwed the cover onto the wall.

Outside, I also fixed the grid to the pipe with the aluminum tape but it came off after a few days due to the heat, so I replaced the tape with small rivets.

Step 5: Connection

On the original pipe of the air conditioner, I added a sleeve to adapt the diameter.

It is also different on the 2 air conditioners in our 2 bedrooms.

Step 6: Cool

Now it's a clean installation, with no loss of cold or heat ingress!

When it's very hot (over 30 degrees Celsius or 86 degrees fahrenheit), I turn the air conditioning on 3-4 hours before going to bed, and turn it off at night. The room has cooled down enough to be able to sleep.

There you go, I hope that my project could inspire you!