Ice Dams on the Roof
When ice dams are located, you will notice a blackish grey or green clouded over center of the roof. Since the roof has been dripping with water for a lengthy winter, the metal melting into water will also be covered with black ice. You might have to search for some other way to identify the location of the ice dam, like rain or snow.
In a well insulated building, the water in the icicles will melt fairly quickly or freeze into a solid block, giving you the large crack your leak was uncovered. However, there are places where this ice will remain, harbouring water. If that happens, the ice block will slowly (within a couple of days), grow larger with the humidity in the building, still forcing it through the roof sheathing, and eventually freezing. You will likely have to place tarps below the water line on the leak, and paint the roof black or brown in order to hide the drip hole.
These tough, traps will hold the water in place without preventing its infiltration through the roof sheathing. If you are in an older building where the roof leaks are not easy to take care of, a drip-repair does not add much to the cost of the roof, because the roof and water meter are usually on the roof, and there are no water stops above roof vents to prevent you from having air circulation in the building.
Flashing and Channels
Tin channels or flashing are also embedded in the roof sheathing to catch any larger leaks. These can be on the recessed standard channels underneath the sheathing or they may be on smaller duct or outlet ducts. Even when the offset output of the vent is not a problem, it might still cause attic drafts in upper floors.
If you are in an older building where large leaks have been spotted, you may have to retrofit your entire house for additional nail joints along certain channels to provide additional insulation.
The best way to tell if more insulation is what you need is to start by checking the temperature of the shingles. If they are warm and covered by ice, you need to install more layers. Even if you don’t have ice dams, the temperature of the roof sheathing may still be too low for your insulation. In this case, retrofitting the roof or both it and the sheathing is normally necessary. We will also show you a few more tricks for fixing roof leaks and keeping the heat in.
Chimneys and Vents
First, you may encounter leaks in the gable-end vents. These are one of the main causes of chronic attic drafts, especially in upper floor houses. In addition, through the attic mean outdoors air-streams, such as those from bathrooms, melting garden leaves and snow, can cause condensation on gable vents. This can affect the air movement through the roof and lead to bringing hot air back up into the attic, slowing the convection of heat from the home.
Finally, sometimes you find leaks in chimneys and vents, because they are frequently the source of cold air in your home. Besides being an air movement bottleneck it is also a large source of true hot air from adjacent rooms, which can cause drafts in the attic.
Many times this can be addressed by installing the hoses from the home’s gas, electric, water and sewer service to the fireplace or any furnace running in the home. This solves the air re-circulation problem, but is far more costly than just making the HVAC system itself better insulated. If the system is not located close to the room you are trying to heat, there may be other alternatives.
It should be pointed out that all the roof leaks we will talk about here are relatively minor and can usually be fixed with some simple tools. The problem is likely to be more serious when dealing with less than strong reinforcements. If the roof is already pretty deteriorated, there are times that patches can be tricky.