I have the same problem with the cellar door in my house.
I have also been researching this and may have found an interesting solution from a site about wine cellar doors. Below is a URL to the page that you can copy and paste into your browser. One of the things I noticed about all of these doors is that they all open width-wise instead of length-wise, so the weight of the door is more evenly distributed along the length of the door
. They slo appear to use some sort of small hydraulic opener. I have to do more research to confirm this. if you haven't found a solution i hope this may be of some help. Good luck.
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