Is it absolutely nessesary to replace an existing non pressuer teated sill?

[ajcrm125]

Our church bought a building recently which is a large steel building with an attached addition. The additoin lies on a conceret foundation and is framed with 2x4's. Not pressure treated lumber was used what I can see... and that includes the sill that lies on the foundation. So my question is... is it nessesary to rip out and replace the sill or do we take a chance and just leave it? The location is in western Massachusetts. My only concern is that they are looking to finish the basement portion of this addition so once the drywall's up... it would be very costly to have to gut it and start over..... again. :-)

Thanks for your input,

-Adam

[marson]

Changing the sill plate would be no picnic, drywalled or not. Of course, pressure treated sill plates are code, and when building new, it is a very inexpensive way to cover your ass. However, many, many times, I have taken apart old work where sill plates weren't pressure treated, and I have seen no sign of rot. Right under where I sit as I write this, is an untreated rim joist with concrete poured in between the joists over the foundation wall. No sign of rot 90 years later. It all depends on how much moisture is expected. How old is this building? Are there any signs of water on sill plate? Always seemed to me that if it was wet enough to rot your bottom plate, you were in trouble anyway, what with mold and such.

[Dave]

Standard procedure to use all non-treated lumber including the sill plate some 2 or more decades ago. They simply placed the sill on #15 felt, with about .5" overhand to the outside of the slab. No reason to replace it based on what you've stated to date.

If the current slab has the old ferrite iron all-thread, the current form of pressure treated lumber will eat it up. You have to go to ceramic nails to retain the new pressure treated sill plate instead. Dave

[Bob Morrison]

If the bottom of the sill is more than 8" above the adjacent grade then IBC2003 does not require a pressure treated sill plate.