There is no residual loss of R-value after it dries, but it's performance can drop to about half to two-thirds of it's dry value when wet. Assuming a dry value of R5.7/inch x 2.75"= R15.7 the wettest pieces are still delivering at least R8 or better. IRC 2009 code-min for basements was continuous R1o, so even when pretty wet it'll be close to that (and still cheaper than new R8-R10 rigid insulation.) But when it dries it will spring back to north R15.5.
An uninsulated foundation wall runs R1-R2 on it's own, so the first R5 does a lot more for performance (cutting heat lossed by 2/3) than the next R5, (cutting that remaining third by less than half) or the third R5 that brings the losses to under 1/10 of the original heat loss. So even before it's fully dried it's doing a lot.
An uninsulated foundation wall runs R1-R2 on it's own, so the first R5 does a lot more for performance (cutting heat lossed by 2/3) than the next R5, (cutting that remaining third by less than half) or the third R5 that brings the losses to under 1/10 of the original heat loss. So even before it's fully dried it's doing a lot.
