How to Address Fieldstone Foundation Connection to Timber?
The timber floor joists in my 1870s built home are notched and sit directly on the fieldstone foundation. Water appears to have entered the stones and mortar, risen through capillary action to the timber, and soaked the timber joists.
In researching how to resolve this properly and there are only two extremely difficult options, and I was hoping anyone would have another option other than the two listed below?
(1.) Disconnect the Foundation from the Timber. Raise the timber joists and entire house off the fieldstone foundation with jacks enough to install pressure treated wood and a capillary break.
(2.) Prevent Water from Entering the Foundation. Dig out the exterior of the foundation walls and apply a waterproofing material then backfill.
(3.) Air Dry. Remove insulation and barriers from the foundation interior and add additional dehumidifiers to allow the water to wick out and evaporate into the basement space faster than the water can wick up the fieldstone to the timber.
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Replies
Option 1 is likely the easiest way to fix your problem. Joists sitting on a foundation without a timber sill is an unusual assembly but actually easier to deal with than having a full sill--just jack up each timber a bit and slide a piece of membrane or metal between the stone and the wood. Preferably a membrane, as metal will conduct heat and lead to condensation.
Can the individual joists be lifted separately? My thought was the entire "platform" for lack of a better term had to be lifted together to prevent damage up the walls.