Thermopane glass that has the low-e coating is not ideal for plants. Most does have it. I go for single-glaze glass. A cold frame can be super-simple or as complicated as you want. The simplest is make a box out of whatever you have, 1x or 2x boards wide as possible. Make the outside demension of the box the same as one or more sash. Make up a growing bed and place the box on it sloping somewhat toward south, 10 degrees or so, just push the south end down and prop up the north end and heap up soil and pile mulch on the north side for insulation. If you don't have hinges just set the sash on the box. On sunny days around mid-morning take the sash off, put them back on mid-afternoon. Cloudy days leave them on or put a block under the sash to ventilate it a little. Works just fine. Take you about 30 minutes.

Since you asked "what would you do?", what I would do (which isn't what others here would do, and I'm not criticizing them) is to fix it with trim. Honestly, I don't think anyone will notice unless you point it out to them. My front door is trimmed below the two windows next to it and I never noticed before this post. I am very particular about a lot of things, but this isn't a battle I would choose since the cost to change is so high and the the resulting fix is so small. When we were building our home 14 years ago, we had a couple of minor probems, both of which our GC offered to pay to fix. We declined since neither were a big deal to us. If it were a question of safety, that's another story. I understand those who say make them fix it. It is your money and you're paying to get what you want. But, you're obviously thinking twice about it or you wouldn't have asked the question. Economic times are tough, and it could be one of the lowest paid workers on the job who has to end up paying for this error. Dee

It appears to be a carpenter's mistake since the intention of the design is clearly stated on the drawings. Perhaps the windows were installed before the door arrived. IMHO there is no reason to replace anything other than the narrow "picture frame" molding; it's really out of place here. Option A (cheapest) Raise the door head trim and find a way to fill the resulting gap. I would also fill the gap between the door and window jamb trims because these narrow strips of wall look amateurish to me. Option B (best) Use 3/8" or 1/2" flat trim that spans from opening to opening, then add a decorative band molding around the outer perimeter of the entire assembly. The flat part of the trim would be a bit larger at the door head but it would look fine since it's at a door not a window. If the carpenter is good he could add a cove, bevel or bead at the inner edges. That is the way triple openings have been detailed for hundreds of years so I'm surprised the architects or the builder didn't suggest it.

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