Customer with a home built 8 months ago. As the result of considerable dampness on the walls they had an S.E. out who determined that the walls were never parged. The builder applied a heavy coat of tar directly onto the green block. My question is, the S.E. now recommends that the foundation be re-excavated, the tar removed and a parge coat applied. Does anyone know if this is viable? Will a parge coat adhere to a wall that has been tarred? I know you would have to remove the tar first, maybe pressure wash or sand blast, but I don't think you could remove all of it, or the tar that has penetrated the pours of the block. Any help or suggestions would be appreciated. Thanks in advance!

Parging would only work if the block was clean. Any ashphalt left on the block, and there will be a lot will make the surface prevent the cement coating from sticking. I would suggest that the surface be covered with expandand metal and then coated over.
Personally however if the parge coat was not applied and the walls were covered in asphalt I do not see why any dampness would be coming through in the first place. Parging is simply cement coating which is pourous in itself. If the coating of the asphalt was properly done along with a plastic layer over it. Properly backfilled with gravel and the drainage pipe installed correctly there should be no reason for dampness to come through.
Something in my opinion is wrong and its not that the walls are lacking parging. Be prepared for some other sort of repair here.

I know your right. I went out yesterday and dug a little. The tar at grade level and down a block was applied very thick, below that it is thin and cracking, you can actually see most of the blocks. No visquine. The builder used insulation boards and nailed them in place, unbelievable. I did however find gravel within a couple of feet. How did this house pass inspection? Thanks for the tip on the expanded metal.

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