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.

Panel Profiles

Roof Panel Profiles - Our standard roof sheeting is the "PBR" panel, which is available in bare Galvalume Plus® as well as a variety of colors. Wall sheeting is available in "R" and "PBR" panel. Depending on the color and your geographic location - PBR panels may not be available for certain colors.

Liner Panels - For liner panels we offer a low-rib 29-gauge panel. Liner panels are an interior covering for the walls of a steel building. Like exterior walls, liner panel consists of 3-foot wide panels that are attached to the framing in the same manner as exterior sheeting. Full-height liners run from floor to roof. Partial-height liners typically attach to the girt at 7'4" and extend a few inches above it. Buildings with liner panels must have a base connection for the bottom of the panel (see base conditions).

Advantages - Liner Panels enhance appearance, providing a finished look for the interior. The biggest advantage is that liners protect the insulation and the outside walls. Because un-reinforced insulation facings tear easily, and even the best-reinforced materials can be damaged, liner panels are the intelligent solution to protect your investment. Although 26-gauge exterior walls can withstand a lot of punishment, a steel liner will protect your building's interior and performs at a lower cost than other wall coverings, which will require their own framing.

Recommended Installation Methods of Insulation

Roof insulation rolls are cut to lengths that will cover the distance from eave to eave, leaving a one-foot overhang on each side of the building.

1) Start at the end of the building and temporarily secure one end of the roll by attaching the insulation to the eave strut with double-faced tape.

2) Pull the insulation across the purlins with the vapor barrier toward the building interior. Double-faced tape attached to the opposite end of the insulation will keep tension on the roof roll while the metal panels are being attached over the insulation.

3) Install the next roll in the same manner, making sure the rolls are stretched tight, aligned properly and closely butted.

4) Fasten tabs using one of the methods described on the following page. Any rips or tears must be covered with matching facing tape to ensure a tight vapor seal.

5) Trim excess insulation flush to prevent it from acting as a wick and moving water into the building.

Before you Buy

Do you know the company you're doing business with? Is the supplier a member of the Better Business Bureau? Do they have a record of dealing honestly? Can they refer you to satisfied customers? Is the physical address to the company available? Can you visit them at their offices? Are they a real company with a history of quality manufacturing? Are they Active Members of the AISC (American Institute of Steel Construction) Do they post any affiliation with any steel building association? Do you know what you are paying for? Does the steel building contract give line-item prices? Will you receive comprehensive set of erection plans? Are you getting written 30-year paint and 25-year Galvalume Plus® warranties? Does the contract specify 26 gauge panels? Does their roof panels include a "purlin bearing" leg? Does the roof system have an Underwriters Laboratories Class 90 rating? Are you being supplied with premium fasteners with a lifetime red-rust warranty? Will your steel building have a sculptured trim package? Are all the clips welded to primary structural components? Are the framed openings factory located? Does the supplier have the ability to engineer a custom design? Will you receive an 80+ page fully illustrated erection manual? Does the supplier have an in-house customer service department? Does the supplier actually manufacture what they sell? Do they process and produce all their drawings in-house? Do they ask you to sign a contract and pay a deposit before you know the total cost?

Frame Types

Unlike any of our competitors, we allow you to price all building frame types. Select from Clear-span or Modular rigid-frame buildings. We allow you the full flexibility to choose Gable, Single Sloped or Offset Peak building shape. By far, we offer the widest selection of building and frame types. For options not available through the online system, you will need to request a special quote.

Clear-span Frames - A clear-span rigid frame offers strength and economy. Since no interior supports are necessary, this design is best when you require large areas of clear and uninterrupted space. Factories, warehouses and agricultural buildings are just a few building types that may utilize a clear-span frame building. A clear-span design does have size limitations. As the desired width increases, the frames will become larger and heavier to carry greater loads across the length of the frame. At some point the cost will outweigh the benefit. Even so, clear-span buildings are still effective for buildings as wide as 150' feet and wider in some cases.

Modular Frames - Modular frames use interior columns to evenly distribute the load; reducing the cost of both the frame and foundation of extra wide buildings. The economical advantages become obvious when a building width is about 100' wide or wider. As a result, almost all buildings 100' wide or wider have interior support columns. Modular designs are often used for large factories and warehouses.

Single Slope Frames - Single slope frames have high and low eave heights creating a roof that "slopes" from side to side. To select a single slope design, you specify one eave height and define the roof pitch. Single slope designs are frequently used for strip shopping centers, offices, and RV/Boat storage facilities.

Just about every steel building has at least one framed opening. It is not unusual for buildings to have several openings. Most openings are created for an overhead door, but can be used for the installation of glass fronts or other entries. Most other online sellers offer "field located" framed openings, which require cutting and fabricating on the job site. Metal Building Depot always provides factory-located openings unless your project requires something otherwise.