Heat Transfer

Effectively controlling temperature in a steel building requires insulation to be present along exterior walls and roof. When a temperature differential is present in an enclosed steel building, heat will work from warmer areas to colder areas until the temperature in the building has stabilized. At the point of thermal stabilization, the cooler (and heavier) air will be present at lower elevations and warmer air will be present at the roofline. The function of insulation is to help stabilize air temperature at more desirable levels. When it is hot outside, preventing heat from transferring into the building is the goal, and of course in the winter we want heat to remain inside.

Heat transfer occurs in three ways:

Conduction : Occurs in a solid or liquid when heat from one object is transferred by touch to another object. An example of this occurs when a pot on a stove will heat up by conductive heat transfer from an electric coil.

Convection : Occurs with the physical movement of air. There are two types of convectional heat movement. The first is natural, where hot air rises displacing the cold air and moving it down. The second type is forced or mechanical convection. This occurs when an object, like a fan, physically moves or "forces" the air to move.

Radiation : Occurs when an object is warmer or hotter than the air around it. For example, the sun, which is hotter than everything around it, radiates heat waves that travel through the air and is either absorbed by or reflected by the surface it comes in contact with.

Ridge Vent

Ridge vents come completely assembled for ease of installation. Ridge vents supplied by Metal Building Depot are of a low profile design to provide gravity type ventilation. Because gravity ridge vents are designed to allow free airflow, some penetration of water during blowing rains is to be expected. Standard available finishes for the ridge vents are polar white and galvalume. Other colors may be available at an additional cost. Nominal ridge vent length is 10'-0". Ridge vents are available with 9" and 12" throats. Bird screens are provided as a standard. The ridge vents can be ordered as continuous or single units. Exterior parts are 26 gage painted or galvalume. Interior parts are all made of G90 galvanized steel. The substructure consists of 10 gage saddle straps with interior baffles of 24 gage steel. Lifter arms and damper slides are made of 18 gage steel. Manual operation is through activation of a pull bar which is attached internally to bell cranked type lifter arms connected to the damper with Teflon coated pins through the damper slides. Dampers are spring loaded to remain in the open position until the pull bar is operated and locked in the closed position. Dampers operate in a vertical manner. Each vent is opened by a pull chain that extends approximately 12" below the roof unless noted otherwise on the order documents. Other opening mechanisms are available at an additional cost upon special request. Ridge vents should not be placed closer than 5’-0" to the endwall steel line to allow room to properly flash the building. For example, a 90’-0" long building with ridge vents required the entire length should have no more than (8) units. The ridge vents are available with the following accessories:

Misleading Information - Deceptive Practices

The standards and values of our industry are regularly masked by the deceptive practices of the unprincipled few. These companies deliberately mislead people hoping to increase their chances of a sale. At Metal Building Depot we know that the more you understand about the product you are buying, the more confidant you will be at purchase time.

Arm yourself with information - No manufacturer keeps an inventory of buildings "ready to ship." Without exception, steel buildings are made specifically to order. A building should be designed to meet your needs and more importantly - your building code. Some companies create "general" price lists for common sizes, but the selection is very limited to a geographic area with limited variance in design.

Beware of companies implying they keep an existing inventory of buildings. To find out whether a "clearance" or "cancelled order" really exists inquire on the earliest ship date. You should be able to take immediate delivery on a building "ready to ship."

There is no such thing as making simple structural changes on a pre-designed building. Moving or adding a door opening on an existing or "ready to ship" building - could require the use of a wind column or portal frame. This could change the rigid frame design and render the existing design useless. Additionally, changing the wind or snow load could require the girt and purlin spacing to change and the location of connection plates along columns and rafters may not be located properly. The bottom line is that a structural change most likely requires a new building design. The moral of this story is: If a seller claims to have a building "ready to ship" make sure it will meet or exceed you local building codes and loads and more importantly - your needs.

Proposal or Propose "ALL" - We want to help you eliminate the "gray areas" in a typical building quote. The items listed on your contract should be made clear as to exactly what is being promised. Our itemized contracts are detailed and specific and you'll never see "included" in one price (without a description). All your accessories and options are listed as separate line items. With our online quote you will always know exactly what you're paying for.

Heat Transfer

Effectively controlling temperature in a steel building requires insulation to be present along exterior walls and roof. When a temperature differential is present in an enclosed steel building, heat will work from warmer areas to colder areas until the temperature in the building has stabilized. At the point of thermal stabilization, the cooler (and heavier) air will be present at lower elevations and warmer air will be present at the roofline. The function of insulation is to help stabilize air temperature at more desirable levels. When it is hot outside, preventing heat from transferring into the building is the goal, and of course in the winter we want heat to remain inside.

Heat transfer occurs in three ways:

Conduction : Occurs in a solid or liquid when heat from one object is transferred by touch to another object. An example of this occurs when a pot on a stove will heat up by conductive heat transfer from an electric coil.

Convection : Occurs with the physical movement of air. There are two types of convectional heat movement. The first is natural, where hot air rises displacing the cold air and moving it down. The second type is forced or mechanical convection. This occurs when an object, like a fan, physically moves or "forces" the air to move.

Radiation : Occurs when an object is warmer or hotter than the air around it. For example, the sun, which is hotter than everything around it, radiates heat waves that travel through the air and is either absorbed by or reflected by the surface it comes in contact with.

Secondary Framing

Secondary framing is created from rolled steel coated with a red-oxide primer finish in gages from 12 to 16 to provide an extremely rigid, and corrosion resistant structure. The following elements are formed as secondary framing:

Girts (walls) & Purlins (roof): These members run the length of the building providing rigidity, and a sturdy skeleton to attach the sheeting. They are rolled from steel coils 12,14 or 16-gauge steel, or thicker if needed. All girts and purlins are pre-punched for ease of assembly.

Eave Struts: This is a rolled member formed into a "C" to match the pitch of the roof. The eave strut is also made of 12, 14, or 16-gauge steel.