Abstract
In order to prevent incoming solar radiation, it is necessary to study about blinds' blocking out effects of heat that are installed at the balcony at an apartment house. To figure out the heating effects from the windows, a study for indoor thermal environment according to the location of blinds is also needed. In order to find out the changes of indoor thermal environment, we'll compare models of a house building with or without Venetian blinds: one place has an extended living room removing a balcony and another one has a normal balcony. The result is as follows. Without blinds, the place with an extended living room has benefits for saving heat compare to the place with a normal balcony. It's because the warm air heated by the incoming solar radiation moves into the living room through convection current and radiation which causes an increase of the indoor temperature. At an extended living room, the temperature difference from outside and inside, when blinds were installed inside, was $1.9^{\circ}C$ while it was $0.6^{\circ}C$ when the blinds were installed at outside of the balcony. It is evaluated that setting up the blind outside prevents much heat. At the space with a normal balcony, installing blinds at living room windows can save much heat compare to installing blinds at windows at the balcony. The indoor temperature was low when blinds were installed. It can be said that blinds block heat from the incoming solar radiation. Moreover, when blinds are installed, there is a big change of indoor temperature due to the radiation from the blinds' slat and convective activities in between the blinds and windows. This also has to be considered.