Any help is appreciated.
First of all, if you want to keep the planks complete and not cut them off in the middle, the intersecting object has to contain the plank object completely, i.e. you have to scale the object "Main House" a little larger so that "Main House.001" is completely inside of it. You can either Scale "Main House" with the S key or better do it this way:
- Select "Main House" (the "clean" house without clapboard planks) and in Edit Mode use Shrink/Fatten with Alt+S to increase the size (maybe hit S again for Even Offset).
- Make it big enough to completely hide the clapboard planks, but do not exceed the roof. Then left-click or Return to confirm the action.
- Now back in Object Mode, select your object "Main House.001" (with the clapboard planks), set the Boolean Modifier to Intersect, choose the "clean" house "Main House" as Object to intersect those parts.
- Now to really see the result you have to hide the surrounding object "Main House". To do that, you have to hide it in the Viewport (the eye symbol in the Outliner) and very important, to avoid unwanted surprises: Disable in Render (the camera symbol in the Outliner).