I do not like the looks of a roll up door plus they use up 2' of your opening requiring a even higher roof. Bob, since you are going to probably go attached you may want to do something like this, especially if you can go lower than the house floor level... every little bit helps.
Here's a picture of the MH bay door. There is a adjustable cable running from the top R to the bottom L... just over the window to support the weight of the door.
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By swing the door you save 2' in the height of the building. The door is made of 2x6's, insulated, and sided with Hardy plank, the same as the house. The pivots for it are 2" pipe nipples screwed into floor flanges. The bottom pipe nipple was installed in the concrete when poured.
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Since it's attached to my house and I have 120 psi water coming in I made a five outlet 155 degree fire sprinkler system.
Thanks MM, I put a lot of thought into my last home before the nursing home:B I even putting windows, doors, and outlets/switches 4' higher than normal so when no longer RVing this space can be converted to living space on the same level as the house. You can see the window and doors at far end at that level.
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