Do mosques built underground differ from others in the reckoning of the reward for steps taken to them?

As long as the place the worshipper intends for prayer is a mosque, he is rewarded for his intention, whether the mosque is elevated or has another building beneath it. However, it is better for the mosque's structure to be independent of others, so that it is not affected by demolition or sale, and no water pipes or sewage from other buildings pass through it.