Building Envelope

Which of the followings is/are the components of building envelope?

Heat can enter or leave a building through its building envelope mainly by _____________ and ______________ .

A metal plate has area A, thickness d, and thermal conductivity of the metal is k, what is the thermal transmittance (U-value) of the plate?

The average U-value of the building envelope (with windows) depends on

(1) the building materials used for the envelope.

(2) the intensity of sunlight shining on the envelope

(3) the temperature difference between the interior and exterior of the building

What is the definition of OTTV?

denote $$Q_c$$ is the heat transfer due to conduction by the walls and the windows,

$$Q_r$$   is the heat transer through the windows as a result of radiation,

$$A_t$$  is the total area of the building envelope

The OTTV of the envelope of a building (with windows) depends on

(1) the building material used for the envelope.

(2) the intensity of sunlight shining on the envelope.

(3) the temperature difference between the interior and exterior of the building.