I bought a 7 year old house last summer. When winter came and the heat turned on, the ducts to my bedroom got very noisy. They were quiet with the A/C on.
I found the large rectangular ducts (obviously I don't know much about HVAC) were made of two pieces of metal, crimped on the two edges where they joined. The crimping was not real tight and they were free to move. I figured the heat for some reason made them move. I put sheet steel screws into the crimps on the ducts going to my bedroom and about 80% of the noise went away. I had to do the entire system to get the remaining 20%.
So my question...
Is this normal or did I get a substandard install? It seems to be a reputable company (on buying the house I found they had vented the furnace wrong. They came back, after 6 years, and replaced all the venting; probably would have cost a couple thousand to hire it done. That's pretty reputable, no?) I can't imagine anyone living with these noises (though my wife isn't sure what I was complaining about) nor can I imagine too many people doing what I did to fix it.