>Basically a modified solid bottom board with a deeper "bottom" Which will become the top, so I can insulate it.
You don't need it "deeper" to insulate it. Just put a piece of styrofoam, or a bag of tree leaves on top and put a brick on that...
> Add a landing board to the front
Waste of time and energy. Bees don't need a landing board.
> and use a standard entrance reducer if needed..
Anything can do. I prefer to use these:http://www.bushfarms.com/beestopentrance.htm#make
which have about a 5/16" gap. Then I cut a piece of screen molding (but you could rip a one by to 1/4" thick and it would work just as well) 2" shorter than the opening and put one nail in the center (up into the cover) to make a pivot. This can then be pivoted open and closed.
> Bee space. this idea will add 3/4 of an inch to the top of the hive. However, I have read that most people just put a shim under their top cover to make the entrance, or prop it up in some other way, which, would also add space in the top. Will this cause problems with burr comb in the top?
Yes. I would try to keep it smaller.
> I understand that cold does not kill bees
I would say it usually doesn't, but with a small cluster and a really bitter cold snap, it does.
> moisture AND cold kills bees.. so I intended to insulate the top cover/entrance, but am not sure what effect having a 14 x 3/4 inch opening IN the top will hive.
Definitely bigger than I would have. The ones I don't have reduced have about a 10 3/4" x 5/16" opening. The ones I have reduced have a 2" x 5/16" opening.
> Having no experience with top openings, I assume it should be reduced in the winter?
Half of mine are... probably would be a good idea if they all are, but I haven't gotten it done.
> I will reduce the bottom entrances to the 1 inch opening, and in effect move the same opening to the top of the hive.
I close all my bottom entrances off... but there is some air leaking around the tray in the ones with a SBB. And some air coming in the screened area on the ones with solid bottoms that were converted to feeders.http://www.bushfarms.com/beesfeeding.htm#BottomBoardFeeder
> Will there still be enough ventilation to avoid condensation?
It really only takes a very small top vent and no bottom vent to let the moisture out the top.
> Will they lose too much heat?
> Will the 30 mph winter winds be more prone to driving into that entrance?
One of the primary things to avoid is a cross breeze. In other words, all the vents should be on the same side, and it's best if that side is away from the prevailing winter winds.
> After much reading and consideration I am going to give it a try on one of the stronger hives I have, but don't want to kill that hive due to lack of experience and consideration..
Just don't get carried away. Bees need to be able to control the ventilation.
I could just prop it open, but... I don't like makeshift remedies when I have the ability to build something correctly.. SO.. in the end, it will have a landing board, which I realize bees don't NEED.. but when I see a bee laden with pollen and nectar crash land on the bottom board and scurry into the hive... well, I know I would be happy it was there if it was me...
Funny, mine never do, but then I don't have any landing boards anymore.
> It will also have a bit of an overhang at the very top to ward off rain from entering, not to exceed the distance the landing board extends
In my experience this is also a bad idea. It catches the wind and causes more rain to blow in. You would need to be a foot or so to have much effect on the rain blowing in and that would just blow off in a strong wind. I prefer no overhangs anywhere to catch the wind...
> with an inch of foil backed foam insulation between the exterior top, and interior ceiling.
I would prefer the insulation above the top.
>It will fit as a bottom board fits, it will not be telescoping, with the exception of the landing board in the front. that will be attached to the sides at a 45 degree angle. I remove my covers from the rear anyhow, so do not anticipate it being a large problem.
I'm not sure I follow this exactly. But if you give the bees any access to the foam where it is inside the and and where it's not protected by the foil, they will chew it up and carry it off.