Modifying bottom chord of roof truss to accomodate new AC

joiststruss

We just had a new AC air handler installed, and it's much taller than the old one. Due to an error on my part, it's actually too tall for the space. And it is deeper than the space between the trusses.

I need to cut a truss chord so that I can make an alcove in the ceiling around the air handler. My plan is run another 2×4 above the existing chord, then use 3/4" plywood on the face of the existing struts and chord with a notch cut out where I need to cut out the chord.

Here is a picture of what I am thinking of doing (red is new 2×4, blue is plywood, black is chord material to be removed):

enter image description here

Is this a good plan? Should I attach the new 2×4 to the existing chord somehow? What should I use to attach the plywood?

Best Answer

Absolutely not. You CANNOT cut a truss in this way. They are not engineered with a huge amount of wiggle room. You risk having your roof collapse. The saner solution would be to lower the platform that the unit sits on to create some more room.