No heat and light don't occupy space and don't have mass because heat is energy. and light is form of energy.
Light is the visible form of electromagnetic waves. All of these waves travel at the speed of light. Light does not mass, because objects with mass cannot have a velocity of 3 * 10^8 m/s. To occupy space, the object must have volume. Since light has no mass, it has no volume. As light passes through your windows, the volume of the window does not increase. This is proof that light does not occupy space. Light and heat are two forms of energy. Energy does not have mass of occupy space. The kinetic energy of a moving object is a property of the object. This property does not have mass or occupy space. I hope this answers your question.