Putting Up A Moisture Barrier Metal Roof

Metal roofs must be laid flat on a vapor barrier because steel will condensate if there s any air space underneath it.

Putting up a moisture barrier metal roof.

To know if you need a vapor retarder ask yourself a few basic questions. Put the steel down directly on a vapor barrier. Single bubble vapor barrier and 2. Metal roof over shingles condensation.

If you choose to omit the plywood from a residential construction install a vapor barrier between the purlins and the metal roof or plan to spray closed cell foam insulation between the rafters to eliminate the temperature differential between the air in the building and the metal. The problem with using. Traditionally we ve insulated the roof panel to try and keep the temperature on the panel from reaching the dew point. One common problem is moisture build up between two layers of roof type which must be avoided.

Whether or not you need a vapor retarder hinges on three main factors your climate your home and the location of the wall you re insulating. Corrosion of metal components even on surface treated metal. When exposed to moisture metal components can oxidize and weaken decreasing the life of your customer s building. Single bubble vapor barrier is a bubble wrap type material that is faced with reflective foil on the upper side and white vinyl on the inside.

We ll add a vapor barrier so the moist air does not flow up through the insulation and condense on the roof. Some people think that they can just install the metal roofing right over the old shingles roof without any barrier in between but this is highly not recommended. It blocks condensation from dripping into a pole barn and runs it out of the eaves as well as adding a slight r value to the roof and also. In metal buildings there are a few possible consequences of trapped moisture in wall and roof systems.

It s also a good idea to discuss the options with your roofing contractor because they will be able to check the type of shingles your roof has and advise on the suitability of leaving the shingles in place or removing them. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter. But a preinstalled membrane may be even more effective at removing condensation.