There is no definitive answer to this question as it depends on a variety of factors, including the type of flooring and the budget. Some people advocate for sealing a concrete floor before covering it with Til, as this will help to protect the floor from moisture damage and also keep the area clean. Others may not find this necessary, depending on their specific needs. Ultimately, it is up to the individual to decide whether they believe sealing a floor before carpeting is necessary or not.