I see that Old World Wisconsin falls under the Wisconsin Historical Society, so this might not apply to you. But I'll put it out here just in case, or for the good of anyone else who could use it.
I'm going to assume that these buildings are in a historical district, or whatever your local government might call it. I suspect a great many museums fall into this category.
I would check with government officials before going any further. You may be limited as to what you can install, including having to go back with it exactly as it was before. (I know that sounds counterproductive, but I find the people that make these restrictions are usually worried more with appearance than building longevity.) Of course, they should tell you all this when you get the building permits, but it never hurts to ask.
Ummm... you were going to get permits, weren't you? ;-)
If you are allowed to cap it, try a google search on "custom chimney caps". There are many different styles and materials available. By the looks of your buildings, I'm thinking a black "wrought iron" look, or possibly pre-patina-ed copper. But then, I'm no historian.
Once you've chosen a cap, I would present it to the government officials and get their approval to use it IN WRITING. I've recently seen where someone was moved into a position of approving these types of things, did so, and didn't know what they were talking about. Of course, it was only discovered AFTER the property owner spent several thousand dollars to find that they were not in keeping with the building codes.
Hope this helps.
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Bill Browne
Westlake LA
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Original Message:
Sent: 08-01-2018 09:29 AM
From: Catherine Dallas
Subject: Chimney Capping Question
Three of the 60 historic buildings at Old World Wisconsin are scheduled for complete chimney rebuilds due to water intrusion through their chimneys (not the exterior flashing). I'm looking for suggestions for unobtrusive ventilated chimney capping ideas. We use the stoves for heating and cooking so the chimneys need to remain functional. However, we must find a way to prevent or significantly minimize direct water intrusion through the open chimney. Modern chimneys of course have the screened raised metal roofs that deflect rain. Have any of you found a way to address this building preservation need while maintaining active chimney use in a way that doesn't detract from the buildings' late 19th century appearance? Thanks for any help you can offer.