Which of the following is NOT a type of construction recognized?

The classification of building construction types is standardized based on their materials and the fire resistance of those materials. Type 1 is recognized as fire-resistive, often involving reinforced concrete or steel, designed to withstand high temperatures and provide significant fire resistance. Type 2 construction is deemed non-combustible and typically uses materials that do not contribute to fire development, such as steel or concrete without the enhancements of Type 1.

Type 5 construction, often referred to as wood frame, is commonly used in residential buildings, where wood and other light-frame materials are prevalent. This type is recognized due to its susceptibility to fire, making it essential for firefighting consideration.

A Type 6 high-rise construction does not exist within the standard classifications, which only go up to Type 5. High-rise buildings can be categorized under Type 1 or Type 2 depending on the materials used, but the term "Type 6" itself is not a recognized classification in building construction standards. Thus, it is not an officially accepted type, making it the correct choice as not being a recognized construction type.