Condensation Control

The condensation process occurs when warmer moist air comes in contact with cold surfaces such as framing members, windows and other thermally conductive accessories, or the colder region within the insulation itself (if moisture has penetrated the vapor retarder). Warm air, having the ability to contain more moisture than cold air, loses that ability when it comes in contact with cooler surfaces or regions. When this happens, excessive moisture in the air is released in the form of condensation. If this moisture collects in the insulation, the insulating value is decreased.

In dealing with condensation, air may be considered to be a mixture of two gases-dry air and water vapor. One thousand cubic feet of air at 75°F can hold up to 1.4 pints of water. At 45°F, it can hold only 0.5 pints.

Relative Humidity is a percentage measurement of the amount of water vapor present in the air in relation to the amount it is capable of holding at that temperature. Therefore, 50% Relative Humidity would mean that the air is carrying only one-half of the total amount of moisture that it could be holding at that particular temperature. Cold outside air is usually much drier than warm inside air. Therefore, you can lower the Relative Humidity by bringing in outside air to mix with and dilute the moist inside air. At 100% Relative Humidity, the air is "saturated."

The temperature at which the air is saturated and can no longer hold additional moisture is called the dew point temperature. Whenever air temperature drops below its dew point, excess moisture will be released in the form of condensation. Condensation problems are most likely to occur in climates where temperatures frequently dip to 35°F or colder over an extended period of time.

Components/Accessories

Which base trim option should I choose? - The base trim that you choose for your steel building will depend on your building's needs and the type of foundation you use. Although we strongly recommend a notched base, we do offer several additional base trim options to suit your specific needs. Please see base conditions for more helpful information and illustrations.

What type of windows do you offer? - We offer a selection of windows for your building. To learn more about what's available please visit the accessories section of our website.

What comes with the doors and windows? - All of our doors and windows come with the required hardware to install them into your steel building. We provide the framing, trim, and flashing for a proper installation.

How do I know where to place my windows and doors? - Windows and walk doors are generally "field located." You, as the customer, will pick the location, cut the corresponding panel to size and proceed to mount the doors and windows. If you choose to include a large number of windows or doors we may ask you to give us your proposed location to ensure proper building bracing.

How do I attach my doors and windows? - All of our walk doors are self-framing, so they include the necessary items to mount them on your building. Our windows are secured by screwing the window trim directly into the building. This is also known as self-flashing. If you live in a high wind area, please talk to one of our design consultants about additional door and window mounting options.

What is the R-Value of your insulation? - The r-value of our insulation depends on the thickness you choose. It will vary between R-10 and R-19. Please see the r-value section of our website for more helpful information.

Perm Rating

The perm rating, or permeance, is a measure of the amount of water that passes through one square foot of material per hour. The lower the perm rating, the more effective the barrier. A facing material with a perm rating of 0.1 or less is considered excellent. Anything with a rating above 1.0 is not considered a vapor barrier.

Facing Types

Popular Facings include:

WMP-VR-R,WMP-VR,WMP-VR-BLACK,WMP-10,WMP-10-BLACK,WMP-50

Specialty Facings include:

WCF-50,WCF-30,WMP-30,Arenasheild,Gymguard,R-3035-HD,WMP-F,VRP-HD,VSF-HD

Controlling Condensation

Two things must be present for condensation to occur: warm moist air and cool surface temperatures below the dew point. The proper control of these two factors can minimize condensation.

In metal buildings, we are concerned with two different areas or locations: visible condensation which occurs on exposed surfaces below dew point temperatures, and concealed condensation which occurs when moisture has passed through the vapor retarder and into interior roof and/or wall cavities and then condenses on a surface below dew point temperature.