I am considering installing an over the range microwave. The microwaves I'm looking at are between 60 - 70 lbs. My concern is that the wall that I would be installing the unit on is made of furring strips, and that the unit might be too heavy.There are already 3 cabinets on this wall where I would be placing the microwave, 2 fulls on either side of the range and one half above the range. I wanted to see if people thought this would be too much weight and see if anyone had any recommendations. Any answers/suggestions are appreciated, thanks.

Please explain a furring strip wall?
As long as there are studs behind the furring (do you mean old plaster and lath by any chance? or paneling with furring in places?) you can attach your microwave. You just need longer fasteners.

Thanks for your response.

I live in a twin house. The wall I am talking about is the wall that is shared with my neighbor. The support for the wall, the furring strips (1x3x8's if I remember correctly), are attached directly to the block wall that separates our two homes. The drywall is attached directly to the furring strips. My concern is that since the wall isn't framed out as a normal wall would be, it may not be strong enough to hold the weight of the cabinets plus the microwave and the furring strips would pull out of the block.

When you mount a microwave on a wall you first secure a steel plate that comes with the microwave. That plate has instructions and how and where to place screws. You would mostlikely use a masonary screw that would go into the block.

You may need to use a toggle bolt on the mounting plate. It would go into the cell space on the block and through the furring strip. You can also screw a piece of 1/2 plywood to the furring and then screw into that with the mounting plate. Remember, much of the weight is borne by the cabinet above, not the wall.