The last few months I've been intermittently working on a DL&W passenger car that needed some floor work done. The floor material is wood joists with corrugated sheet metal and a very thin layer of cement (probably 3/8" at the top of the corrugations). The problem I'm running into is that the metal is rusting out from under the cement, causing it to lose the structure, which causes cracks in the cement. The metal's already rusting pretty good in spots, but it is about 90 years old at this point.

I cut out the worst spot (it flexed too much to bust out any other way than to cut it) and replaced it with just reinforced cement. We can always remove it, but to replace it properly would require the whole car, which is beyond what current volunteer time and the budget will allow, and rust pretty much eliminated most if not all of the historical fabric of the area already. The patch seems to be holding up quite well. But having worked on it, I foresee this thing requiring quite a bit more repair over the next few years because now I know what I'm looking at when I see those kinds of cracks.

As I see it, we can't replace it all with a thicker cement slab like I did for that repair without adding too much additional weight. Cement board with a finish coat would function, but would not be historically accurate, and I assume would probably tend to crack at the joints. If we do any less than the entire car at once, I could see the edges of a direct replacement of the corrugated and cement cracking/breaking at the edges of the patch from flexing, and I'm not sure we could match the corrugation pattern without custom bending it with a brake and a lot of time.

So, that leads to my question: What experiences have people had with both patching and complete replacement techniques for this sort of floor?

A good place to start is with the "search" function on this forum. You will find this topic has been discussed at length before.

http://www.rypn.org/forums/viewtopic.php?f=1&t=32080&hilit=concrete+floor

http://www.rypn.org/forums/viewtopic.php?f=1&t=32089&p=163634&hilit=concrete+floor#p163634

Alan Maples

Ah, sorry about that. Thanks for the pointers.