Do they have the furnace on higher then your own apartment? When was the last time they clean their ducts? A house may appear cleaner but that is not always the case. I knew this one lady that kept her house spotless and I mean spotless....she then had her ducts cleaned because she and her family were suffering from breathing troubles. It turned out that the last time the ducts were cleaned was over 15 years ago. That's quite some time to have the dust gather. She was shocked to discover how much dust and dirt had accumulated. I don't know if this is the case with your parents house or not but it's just a suggestion.
Oh and btw, Welcome to Healingwell :)
Uc(Left-sided) since 1992 - Colazal, 6MP, Biotin, Forvia
Secondary Raynauds Syndrome since 2004 -Meds - Norvasc...Fibromyalgia since 2006
Co-mod for Ulcerative Colitis.....Moderator for Allergies/Asthma
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