Slowly but surely, my energy efficient shed project is moving along. Already, I’m very happy with how it is performing.  It holds heat late into the night and stays cool during the day.  It’s so air tight, you can feel the air pressure/vacuum as you open/close the door.

Two questions:

1) I’m almost ready for siding and had a bit of a revelation as I prepare the trim blocks for two exterior lights and a plug.  Rather than build them now, I will wait until my siding reaches that height and then I can locate the trim block in the optimal location to make integration with the siding easy.  I can’t move the location of the lights but I can alter the location of the hole within the trim block and the overall height of the trim block if I wait to build it until I see where the siding will land.

I’m thinking this would be optimal:
1) The siding above the trim block should be flush with the top of the block (no trimming needed)
2) The piece of siding at the bottom of the trim block should need to be trimmed by the height of the overlap between courses (about 1 1/4″)

Does that make sense? That would mean I only need to jigsaw a single cut and it would be at the very top of the siding so it doesn’t even need to be that clean (there will be overlap from the next course of siding.)

Diagram attached.  Trim block is the grey block with a black outline.
The top of the trim block is located so that the red course of siding does not need to be cut.  I could do a jigsaw cut for the blue but would more likely just use two separate pieces and a small starter strip.  Yellow is two pieces.  Brown has a small jigsaw cut that is then hidden.

2) I did (possibly overdid) a good job at using a planer to add a slope to the outside half of my door sill.  After flashing with tape, I then added shims to ensure the door sill would be rock solid when you step on it.  It is an outswing door.  I’m looking at the gap under the door now and I can’t help but feel that it is going to be a source of cold intrusion.  Even if the door sill is fully caulked, the cold air will be able to reach the inner metal door sill and there will be thermal bridging.  I’m thinking of shoving some rockwool insulation into the gap.  It shouldn’t be getting wet under there… but if some water does end up in that cavity, it will be able to flow through the Rockwool and the Rockwool doesn’t mold.  Does that make sense?