Originally Posted by
Steve D'Gerolamo
There's a lot of talk about lawyers and litigation here. I'm not going to retain some $200/hr lawyer to fight for a new $80 fan.
That is understood ... on that one issue, that would be a no-brainer, but, considering your other issues ... ???
You also asked for "What is the code requirement of sizing of residential bathroom fans" and Scott provided that, but, as is typical, minimum code compliance does not produce the results you are looking for.
Minimum "code" and usefulness is not always the same.
The whole purpose of my post to find an appropriate way to go forward to my builder with facts gathered by me and a licensed home inspector for coverage under a New Homeowners Warranty.
And that is a very good starting step, one step that not everyone takes.
Sometimes, though, you need to do more, and at this point you do not yet know what other steps will be needed, and you will not know that until you get the builder's response. At that time, though, you may need to seek other options, options we were suggesting you could use, options only you will know when and how to use them (we are not aware of all of the particulars).
I'm a firm believer like most of you that a picture is worth a thousand words but data from a reliable scope or meter is useful in troubleshooting a mechanical component.
Except that you are not trouble shooting a mechanical component, you will be trouble shooting a system which is not functioning as you wanted, but which is may be functioning as designed and intended.
I have an Airflow TA45 thermal anemometer and can take some measurements but a simple tissue or smoke test will confirm is there is minimal draw.
50 cfm is minimal draw. If the damper on the exhaust fan is open, that fan should hold a tissue up against it. If it does not, then the damper may be stuck closed, or there may be another problem with the duct from the fan, such as the duct being bent back on itself too sharply, partially collapsing the duct, or at least reducing its effect internal diameter. If flexible aluminum duct was used, it likely could be crushed in one area.