There are issues that aggravate condensation and those situations can be a threat to your roof. If you know what’s involved with condensation, you should be better able to deal with its possible effects. In simple scientific terms, condensation occurs because of moisture in the air. Condensation forms on a surface when moisture and warmer air connect with a surface area that has reached a temperature that is colder than the air. As a result, water droplets or condensation forms.

Different kinds of factors and situations are going to allow condensation to accumulate and there are strategies to alleviate them. Here are some of the causes of condensation build-up along with ideas that might be of help in dealing with them.


If water is leaking through your roof system, particularly when it’s raining, damage could be occurring in a number of areas. Deteriorated or already damaged shingles could cause condensation to build, as would a bad installation job. Roof flashing that is in poor shape or is allowing rain water to seep in at entry points could also affect moisture build up. A bad siding installation or window sills that are damaged could also be affected by a hard rain. Any of these types of leaks that lead to the accumulation of moisture and condensation can normally be checked by a roofer and repaired.

Ice Dams

Another type of leak that can cause condensation build up comes in the form of ice dams. Ice dams are pretty much unrelated to initial roof installation problems as they are actually the result of the effect of warm air that has ventured into an improperly ventilated attic area, which can result in snow melting on a roof. The melted snow accumulates and freezes to the extent that a glacier like expansion is created (ice dam). Although not as easy as it looks, and should be approached with caution, eliminating the development of ice dams can start with snow removal. You want to eliminate as much snow as possible before ice dams develop and condensation makes its headway into your roof system. It’s best to call in a professional for this kind of snow or ice dam intervention.


Frost usually occurs because of build up in an attic. To eliminate frost in an attic space, any air that leaks into it needs to be greatly diminished or eliminated. Reducing the air leakage and accumulation of condensation will involve an increase in ventilation, which means choosing and effective insulation that is properly placed or making changes in the ventilation system in order to eliminate frost and condensation. These changes should be made for an attic space to remain free of frost or condensation.


In older roofing systems, porous and permeable membranes were installed as temporary weather proofing, ahead of a final roof installation. This type of membrane is protective of a roof and provides protection from intense weather and exposure to rain, snow and other conditions that could have serious effects on a roof. A membrane consists of roofing felt that is subject to taking in water and moisture and will not eliminate accumulated moisture from a roof.

In spite of the benefits of these permeable membranes, they can cause condensation to develop that will also damage steel or wood trusses and other parts of a roof. Both corrosion and instability will occur, and your ceiling will be damp as well. Even the more breathable type of roofing membrane is unable to deflect the effects of ceiling moisture. In order to minimize condensation issues, more advanced membrane materials can be used to alleviate moisture accumulation problems.


The use of insulation, particularly thermal insulation, is one of the main causes of condensation that develops in the ceiling of a roof. The damaging effects of moisture can result in costly maintenance and repairs. The use of very thick thermal insulation in roof spaces can lead to lower temperatures and, in turn, an increase in cooler temperatures that bring about condensation. Again, insulation that is carefully chosen and properly installed is one way to avoid the effects of condensation.

Wood Burning Stoves

Another cause of roof condensation is wood burning stoves. A wood burning stove will oftentimes permit the expanse and lift of moist air, while cold air is left behind. Once the quick rise of the warm moist air reaches the roof and its spaces, contact is made with cold air and condensation occurs. This leads to damp spots on ceilings and inevitable damage. Dealing with the problem means preventing the moisture from getting to the roof insulation. It also means making sure that there is enough ventilation as well as proper air circulation in the interior of a space.


Extraction Fans

There are fairly simple ways to limit condensation from getting into spaces of a roof and other areas of a home. One way is to simply install effective extraction fans in bathrooms and kitchens. This step will significantly reduce moisture in a home. There are extractor fans that contain powerful built in ducts that are able to withdraw a large amount of air, with limited noise and energy drain. They can be mounted on ceilings or walls in bathrooms. You do need to watch for gaps in and around any extraction fan installation as moisture can still get into those gaps and spread up the wall and into the ceiling. So sealing is imperative to close the gaps.

With kitchens, extraction fans are usually found under the range hood and also through fans that are placed on walls in the vicinity of an oven or stove top. A kitchen exhaust fan should be vented to the outdoors, and duct work should be properly placed and installed in order to improve air flow. Whether it’s moist air or cooking odors, there are exhaust fans that can filtrate the air without that same air being recirculated in a kitchen space and other rooms.

Sealing Loft Access

Sealing the access to your ceiling loft area is important. You want a comfortable seal to be established in order to prevent moist air from reaching the upper roof space. Using a reliable and proven insulation material will help maintain a seal and prevent air from reaching the roof area. This action can significantly limit moisture and the formation of condensation from spreading into other areas of a home.

Roof Ventilation

Roofing spaces must have adequate pitched roof ventilation to prevent the development of moisture. Ventilation openings should be clear of any obstructions in order to boost roof ventilation, enhance the release of moisture and decrease the possibilities of condensation. Increased vent openings on a roof’s surface can greatly improve loft ventilation. A roof that has enclosed soffits should also be equipped with added vents in order to improve ventilation.

Condensation can be a threat to your roof, especially if it’s not kept in check for any of the conditions given here. When you know that dampness is a problem in your ceiling areas and you’re constantly experiencing condensation build up in the kitchen, bathroom or other areas of your home, it’s time to take action. If you need help or want to schedule an inspection, complete the online contact form and a roofing expert will get back to you with the answers you need to stop condensation in its watery tracks.