The Ductwork Over the Kitchen Ceiling Leaks

Finding the Leak

• Tiny cracks are hard to locate on duct work, and you may have more than one area that is leaking. Turn on the heat or air conditioning and stand underneath the duct. Use your hand to see if you can feel any air flow. Another easy way to tell, especially with small leaks, is to hold up a tissue and move it along the duct. When you reach the leak, the air flow will push the tissue outward.

Temporary Fix

• If you are planning on having a professional come out, or you prefer a quick and easy fix, duct tape is the best solution. This tape can be purchased at any hardware store and is designed for precisely this application. Cut a strip of tape off the roll and press the strip firmly over the leak. Smooth out the entire strip with your hand and pay special attention to the edges. Hold the tissue up again to test the air flow to see if you missed a spot.

Permanent Fix

• The permanent fix for this problem is actually quite easy. You will need to have duct mastic, which is a type of adhesive, and mesh tape. These can be purchased at a hardware store. Apply a thin layer of mastic over the cracked area. Add a strip of mesh tape and press down firmly to create a seal. Let this cure for at least eight hours and test the area again to see if the leak is sealed. If not, apply more tape over the area to create a better seal.

When to Call a Professional

• When you inspect the duct work, if you see a seam that is rusty or appears to be falling apart, or if you notice a crack that is larger than a 1/4-inch in width, a professional should be called in. In this instance, new duct work will have to be cut to fit and the seams will need to be redone. Sealing large cracks like this with tape or mastic will not be effective -- there is simply too much area to cover.