Roof Insulation Condensation Problems

This applies to both the timber and steel trusses.

Roof insulation condensation problems.

If your roof deck or insulation is developing water droplets chances are your forehead is too. But with proper design and maintenance principles you don t have to sweat roof condensation issues. This is another major problem which is starting to affect more homes as the government word gets around and our nasty insulation companies are promoting free insulation paid for by the taxpayer. It s no surprise that this tends to occur more in colder months when home heating is more common and intense.

Usually this problem stems from either poor workmanship in installing the roof or insulation insufficient ventilation or excess moisture in the building. It is the leading cause of the deterioration of trusses. The loft insulation means the roof space is colder than before which encourages condensation in the roof. In the case of the timber trusses and purlins they will rot and eventually lose their stability.

Metal roof over shingles condensation metal roofs must be laid flat on a vapor barrier because steel will condensate if there s any air space underneath it. As it cools it can t hold as much moisture. The rapid cooling leads to immediate condensation. In properties 20 to 80 years old condensation can be a potential problem particularly with the recent drive to insulate houses by putting thick layers of thermal insulation in lofts and to reduce air infiltration by stopping draughts.

Picture a cloud of moisture floating overhead between the rafters. Our photograph at left shows severe alligatoring on a nearly flat low slope roof that also was relying on tar and roof cement to try to stop parapet wall leaks. Although condensation in roofs may not seem like a serious problem it actually is. Do your research check the claims the insulation companies make.

Flat roofs and low slope roofs also face potentially serious condensation problems that can in turn lead to costly rot or mold damage in buildings. Although moisture problems in the roof assembly can be due to waterproofing deficiencies don t neglect the effect of condensation. Roof condensation has a very specific cause. It doesn t matter if the air space is a half inch or six inches because the condensation factor will remain the same.

Warm wet air rises and meets the cold roof and cools. Moisture occurs when heated air inside the home rises up to the roof where it meets the colder temperatures of outside air. Essentially condensation occurs at night when the temperature inside a building is warmer than outside. Loft insulation causes condensation and rots your roof timbers.

That excess moisture ends up as drops of condensation on the roof.