This study is suggested tilt window type to be restrained solar radiation through vertical window type in buildings. The shading and aesthetical effect of buildings would be solved by installation of tilt window type. For investigate optimum an angle of tilt window and building azimuth in reference region, the distance of transmitted solar radiation is calculated. The results of calculation showed optimum an angle of tilt window is obtained $7^{circ}$ that the distance of transmitted solar radiation is 20% of 1.5m of balcony width. In case of an tilt window angle of $7^{circ}$, the optimum building azimuth is showed $SW15^{circ}{sim}SE15$.