<em>Fortunate</em> is an adjective, but its use in this sentence is not correct. It has the same effect as other adjectives, for example, happy. If we used happy in the same way, the sentence would become: "It is happy that you..." So, to fix the sentence, it's possible to write it: Fortunately you are able to fix the faucet..." or We are fortunate that you are able to fix the faucet..."
