It is a misconception that hollow metal doors are actually hollow. In this guide we explore what hollow metal doors are actually made.
Cold Rolled Steel
The exterior structure of a hollow metal doors is made from cold rolled steel sheets. The thickness of the steel varies, with an 18 gauge thickness being the norm for commercial block or brick buildings. 20 gauge thick cold rolled steel sheets are typically used on pre-engineered steel metal building construction. For buildings that require a heavier duty hollow metal door, 16 gauge cold rolled steel is used.
Insulated Core
Within the hollow metal door is an insulated core. The two most common insulated core types are a polystyrene core and a honeycomb core. To better understand the difference in the core properties we must understand what the U and R value mean of each core type. The U value refers to how well the door keeps out solar heat. The lower the U value the better the hollow metal door keeps out heat. The R value refers to how resistant the hollow metal door is from heat. Typically the thicker the material, the higher the R value, the more it resists heat.
Honeycomb Core
Many contractors request honeycomb core hollow metal doors. It gets its name because the cutaway of the core looks like honeycomb from a bee's nest. Within the hollow metal door is honeycombed shaped cardboard. The U range differs among manufacturers but can range anywhere from .53 to .59. The R value ranges from 1.70 to 1.90.
Polystyrene Core
A polystyrene core is foam type core. The U factor range of polystyrene hollow metal doors is .35 to .41. The R value range is 2.40 to 2.80.
Located in a port city, China Dalian Golden House Door & Window Manufacture Co., Ltd. is a large-scale enterprise specialized in producing American-Standard steel fire doors and wooden fire doors. Our company produces 50000 sets of steel fire doors and 20000 sets of wooden fire doors every year. Our fire door products have passed UL Approvals AND FM Approvals and INTERTEK(WH) approval successively. Moreover, our fire door products can be sold directly to more than 20 countries over North America, Latin America, Middle East and Africa.
We respond to tendency of international fire doors market, and provide good service combining foreign clients' needs, with an aim of expanding a wider international market. In the future campaign for world market, our foreign trade elites will achieve better sale performance through unremitting efforts and dedication.
please get into the contact with servicer if need to learn more on the product price and size forcustomized service . also please contact us on alibaba
