6 (Big) Problems That Look Like Roof Leaks

Leaks are found many places and are often easy to diagnose. However, some leaks are not so easy, yet are just as damaging, and can even become dangerous! If you believe that you have a roof leak, and are uncertain of its source, consider that it might be one of these six issues that often present themselves as roof leaks.


1. A Disconnected Gas Vent

Once in a while, and for various reasons, a furnace or water heater gas vent can become blocked or disconnected. This can cause a very dangerous situation. The poisonous exhaust gasses of a water heater or furnace often run up through the walls and attic, before being vented outside the home. In our own experience here are some ways that these pipes can be hindered from operating properly:

  • We have discovered small animal nests (such as squirrels) completely blocking a vent pipe. When the heat is turned on, the animals unfortunately do not survive, leaving a very unfavorable situation for the homeowner.
  • We have discovered that after roof work, furnace work, or just due to time that the vent pipe has come apart in the attic or walls.
  • These roof vents have a cap to prevent rain and snow from going down the pipe, but sometimes these caps slide down tight onto the pipe, preventing the exhaust from escaping.

Common identifiers for a disconnected gas vent can include:


A furnace or water heater that is not running properly. Most modern units also have a few fail-safes in place that detect carbon monoxide or other problems, and will shut off your furnace or water heater in the case of a problem. On this note please take time today to check for the proper operation of your carbon monoxide detector!

If the vent pipe is disconnected, you may see water marks on the ceiling, walls, or even in your utility room. The exhaust is loaded with moisture, and if it is not ventilating outside, this moisture can build up and cause water damage, hence why it can be mistaken for a roof leak.

If you have a sudden appearance of mysterious staining on your celling around where a vent is, call in a professional straight away to inspect the vent and make sure that dangerous gasses are not being trapped in your home.


2. Window Leaks

There are innumerable reasons why a window might leak, from being old and rotten, to improper installation, or lack of basic maintenance. If your roof appears to be leaking, but there is a window at a higher elevation in the vicinity, there is a very good chance a window can be the culprit.


Common problems and fixes.

A rotten window is easy to identify. Unfortunately it often warrants the replacement of the window, and possibly also siding and wall framing repairs if the window has been allowing moisture in for an extended amount of time. However, some rotten windows can be repaired. A window that was not installed properly can be the most difficult to identify, unless perhaps the leak started after a window replacement. Finally if the window or trim have not been maintained properly, water can be getting in around the window.

If a disconnected furnace vent or a leaking window are not the cause of your suspected roof leak, and you’re still puzzled as to the source of the problem, see our second post on Big Problems That Can Present Themselves As Roof Leaks, for four more possible answers as to what is causing the leak.