PURPOSE: To lessen the vertical dimension of a shutter cover by taking up and unwinding a shutter curtain with two parallel take-up shafts juxtaposed back and forth from the front to the rear of a house.

CONSTITUTION: The upper end of a shutter curtain 20 is coupled with a shutter curtain taking-up and unwinding means 30 disposed in a shutter cover 10. The shutter curtain winding-up and unwinding means 30 is composed of two horizontal take-up shafts 31 juxtaposed in the direction from the front to the rear of a house 60 and a motor 32. Drums 33 are secured fixedly to the proximity of both ends of the respective take-up shafts 31, and a chain band 34 is trained over both drums 33 while the upper end of the shutter curtain 20 is coupled with the chain band 34. The rear face of the shutter cover 10 at the house 60 side is provided on a mounting base plate 12. A slit 13 is provided on the lower surface of the shutter cover 10. The shutter curtain 20 is taken up by two take-up shafts 31.