A lot of people experience sound pollution in their home even though the demands for sound levels are met. The majority of new constructions does not only fulfill the basic requirements but also reach the higher classifications that are presented by the Swedish Standards Institute. Even though this is the case, people still make complaints about being disturbed by noise. Bjerking AB states that they require an inquiry if it is possible to mask the noise from a disturbing sound with a background sound. The study also investigates if it is possible to mask the noise even more with a filtered background sound. The thought behind the masking of the sound is to add a background sound that is able to cover the disturbing sound and therefore make it harder to perceive. A test environment has been created based on the question about the possibility of masking a flushing sound from a toilet with a background sound. Twelve test persons have participated in the test using a signal when they identified the disturbing sound during different test scenarios. The result showed that it was in most scenarios possible to mask the disturbing sound with background sound and even better with a filtered background sound. Continuous research is needed to create a more secure method that studies the possibility of masking flushing noise from a toilet. Other types of noise should also be studied to gain a broader picture if masking can be applied to mask noise in residencies.