This problem may become more common as existing buildings are altered to become eco friendly.
Flat roof condensation problems.
Flat roofs are known as being problematic with many suffering leaks.
Flat and low slope roof designs to avoid moisture condensation problems flat roofs call up a whole new breed of building moisture problems how to avoid moisture traps under flat roofs avoid mold rot caused by moisture trapped under un vented flat roofs questions answers about the cause cure prevention of moisture problems in flat roofs and similarly hard to ventilate structures.
If condensation becomes a problem for your roof there are several effective solutions to consider.
Although condensation in roofs may not seem like a serious problem it actually is.
It is the leading cause of the deterioration of trusses.
Keeping your flat roof condensation free is vital for longevity.
As it cools it can t hold as much moisture.
But with proper design and maintenance principles you don t have to sweat roof condensation issues.
Modern living insulation condensation and mould in times gone by houses would have had single glazing air vents built into the brickwork and open fireplaces that would have literally drawn any stale air outside.
Warm wet air rises and meets the cold roof and cools.
Essentially condensation occurs at night when the temperature inside a building is warmer than outside.
If your roof deck or insulation is developing water droplets chances are your forehead is too.
However doing so increases the risk of condensation forming on the elements not surrounded by insulation such as cold roof decks.
Picture a cloud of moisture floating overhead between the rafters.
However in my own experience the problems with leaking flat roofs are usually as a result of either poor workmanship installing the roof membrane poor maintenance by the building owner or as a result of age.
Condensation is a particular problem in roofs above rooms which generate a lot of moisture such as kitchens and bathrooms.
Condensation will be visible on windows but not usually on walls until the problem is bad or has caused the growth of black mould.
Left unchecked or unnoticed this condensation can cause serious structural problems.
There are two forms of flat roof construction which can reduce the risk of condensation forming.
A flat roof should be designed to minimise condensation and a condensation risk analysis should be undertaken taking into account positioning of insulating materials vapour control layers ventilation thermal insulation.
That excess moisture ends up as drops of condensation on the roof.
The cold deck solution.
It can also reduce thermal insulation performance which can be a particular problem during winter.
Although moisture problems in the roof assembly can be due to waterproofing deficiencies don t neglect the effect of condensation.
Despite the many benefits of using the old roofing styles which involve the incorporation of selectively porous and completely permeable membranes they are the major causes of condensation in roofs.