What happens if a roof isn't ventilated properly?

They state that poor or non-existent ventilation can cause attic temperatures to rise to 150 degrees or higher in summer. This can cause damage to roof tiles and other roof materials, as well as condensation to build up and form mold and mildew.

Without adequate ventilation, humidity increases with warm air and forms condensation on the inside of the roof cover.

This moisture is released into the air inside the house when bathing, cooking, planting plants, washing clothes, and other causes. When condensation forms on the roof cover, the wood begins to rot. This introduces mold spores into the air and damages the wood.

The result, if the problem is not detected and repaired, can be the total or partial destruction of the roof covering and the creation of unhealthy air inside the house. If your house lacks sufficient ventilation, you can create an overheated attic. Without air moving through space, the air trapped inside begins to heat up with the sun falling on the roof. This heat is then transferred through the attic floor and begins to heat the rooms in your home. This, in turn, leads to higher energy bills, as fans and air conditioning work to combat it.

Another problem with the fact that your attic is overheating is the lifespan of your roof tiles. The heat from the attic will not only be transferred to the living room, but will also be transferred to the ceiling itself. This causes the shingles to overheat, essentially frying them and reducing their lifespan. When a lot of warm, humid air is trapped in the attic, that moisture will cause mold to grow.

One of the reasons why adequate roof ventilation is important is to prevent and reduce moisture build-up inside the house. A roof with adequate ventilation allows heat to escape, reducing the workload of the air conditioner. If your home is protected with asphalt roof tiles, you may notice that the tiles begin to form suction cups, bend or blister if they get too much heat in the attic. Ice buildup occurs when heat from inside the attic combines with heat from the sun to melt snow and ice from the warm roof.

Roofs that don't have adequate ventilation actually fail one of the purposes they were designed for: they help maintain the interior temperature. The roof is not only supposed to keep the elements and precipitation out of the house, but it should also let hot air escape in the summer months without letting it in to make the house as energy efficient as possible. If the warm air rises, the accumulated heat and humidity would rise into the attic and come out through the roof vents. The roof ventilation system works by providing a continuous flow of air through the attic, helping to remove superheated air and moisture from the attic and roof system and reducing the impact of changes in temperature and humidity both inside and outside the house.

A well-designed roof ventilation system also helps eliminate moisture in the attic and in tight spaces, as it allows fresh, dry air to enter and expels warm air and moist. Depending on the climate you live in, a lack of adequate ventilation can have a serious impact on your energy bills and the lifespan of things like the roof. This occurs when the heat inside the attic melts the snow on the roof and then refreezes in the gutters and forms an “ice dam”. Located in the Midwest, where winters are harsh and summers are humid, we have dealt with damaged and poorly ventilated roofs like yours.