I am going to be attaching a piece of wood to a thin window sash in order to attach a rather heavy window fan to it. I will be using a wood screw to attach the fan housing to the strip of wood (I cannot attach the fan housing to the window sash directly since the wood needs to be wider - and I want to avoid doing damage to the sash, if possible; I hope I'm using term sash correctly: the side strips of wood that the window frame is attached to).
The problem that I see is that the space between the screw head and the fan is essentially nothing (maybe a 1/2") - not enough room to use a standard screwdriver to access it. Since I may want to take the fan out annually, I need a screw that can be accessed fairly easily.
How wide should the strip of wood be to accommodate this screw that you suggest, and the weight and vibration of the fan? Last question, what type of nail/screw or whatever should I use to attach the strip of wood to the molding?
I want to install this fan in the window - so the window can be closed (the typical installation for this type of whole house fan). I must leave a 1/4" gap between the vinyl window and any screws that go into the frame (in order to avoid damaging the integrity/warranty of the window and allowing space for the lip of the window for opening/closing).
I thought attaching a piece of wood to the sash (inner) would be better than trying to reverse the shields and try to attach it to the outside molding because the storm shields would leave a gap; this loses the efficiency of a whole house fan if there is a gap.
Because of the weight of the fan (and its top heaviness from the motor) I plan to put at least an 8" board on the window ledge to help it from falling and putting too much stress on the rest of the attachment points - with the vibrations and all. And legs, if needed. I've seen others make a box but I'm not sure how to do that.