Can you buy a house with BTC? Yes! All you need is a buyer with coins and a seller that will accept them. The value of the transaction is as of the date of the contract, when the coins change hands.
Of course yes, there are ico's out there who are accepting cryptocurrency to purchase a house like atlant, atlant is a successful real estate ico and there are more of this similar projects that is running today so you can look for ico that will provide you your own interest on purchasing a house in this forum.