Seller didn't disclose damage which costs me big money

[Michael Stole]

This is about my residence in Ottawa. Recently, we found two leakages in my house due to poor roof condition, though the roof is installed in 2012. There is enough evidence that the leakages existed before the transaction, and the seller temporarily covered them for sale. The seller didn't disclose these damages. It will cost me over $8000 to repair the wall and ceiling and redo the roof. Can I ask the seller to pay part of the cost?