Proper ventilation is an essential part of any plumbing system, especially when it comes to a kitchen sink located under a window. Venting the sink under a window involves connecting the sink’s drain to an exterior vent, which allows air to flow freely and prevent blockages and unpleasant odors.
Here are the steps to follow when venting a kitchen sink under a window:
Step 1: Determine the location of the vent
Before starting the venting process, it’s important to determine the best location for the vent. In most cases, the vent is installed on the roof or the side of the house, depending on the layout of the plumbing system. You’ll also need to determine the size of the vent pipe based on the size of the sink and the length of the drainpipe.
Step 2: Cut a hole in the wall or roof
Once you’ve determined the location of the vent, you’ll need to cut a hole in the wall or roof to install the vent pipe. If you’re cutting a hole in the roof, make sure to seal it properly to prevent leaks. You may want to hire a professional to do this part of the job to ensure that it’s done correctly.
Step 3: Install the vent pipe
Next, install the vent pipe from the sink drain to the exterior vent. Make sure to use the correct size pipe and fittings for your plumbing system, and secure the pipe with brackets or straps to prevent it from shifting or sagging over time.
Step 4: Connect the vent to the sink drain
Connect the vent pipe to the sink drain using a T-fitting. This fitting allows the vent to be connected to the drain while still allowing water to flow freely. Make sure to use PVC cement or other approved adhesive to secure the fittings in place.

Step 5: Test the system
After installing the vent, test the system by running water through the sink and checking for any blockages or leaks. You may also want to run a smoke test to check for any leaks in the vent pipe.
In conclusion, venting a kitchen sink under a window is an important part of any plumbing system. By following these steps, you can ensure that your sink is properly vented, and that unpleasant odors and blockages are avoided. Remember to take the necessary safety precautions when working with plumbing systems, and if you’re unsure about any part of the process, don’t hesitate to contact a professional plumber for assistance.