Lost episode !!

Hi people,

I once saw an episode Bob was doing and cannot recall the title or channel it was on.

It had to do with a Shaker home that was 99.9% re-produced the way Shakers would have done it. There was a feature missing. Something about Casting iron. It was in Massachusetts. I live in Mass, would like to visit the place cuz I`m a Shaker history buff and have worked on ( Superior Roofing ) origonal Shaker built homes in the Littleton, Ayer, Harvard,Shirley,Groton areas.

Can anyone tell me how to locate this episode,or what feature was missing on the house?

Any help appreciated...Thank you !!