Floor Weak in area of floor register

[carlson]

We have a 2005 3500mRL.
The floor between the kitchen register and the stairs has gotten rear weak and sags.
Has any body has this problem and what is the fix, the weakness is right over the heat duct.
Need HELP!!!

[Bill and Ann]

Is there room to add support from the underbelly Sven?

[DHenry]

I have the same problem around the register in the bath area. I crawled up into the basement and drove some wedges in between the metal stud and the sub floor but that did not seem to help much. I am looking forward to seeing what others have done to stop squeaking floors.

[SlickWillie]

Same problem here with the area around the floor register in our kitchen area. No squeaks, just spongy. Looks to me that the duct is right against the floor; not sure what to do for it.

[carlson]

Will,
That is the way that I see it.
I bought a Ridgid "SEE SNAKE" which is a camera with a 30" snkae on it.
I am going to look inside the heat duct and look up from the bottom and see if I can get some support or anngle iron put in.
I want to fix it as we are looking at putting in a new floor.

[Waynem]

My 3400RL squeaks in the living room. 1 year warranty is up in August and I'll be home before then. It's going in to the dealer to get fixed.

[carlson]

took up the floor and rugs today to get ready for new flooring tomorrow and found out why the sag in the floor.
When they cut out for the registers, they simply do a plunge cut with a skill saw and over cut the hole.
So the cut is long on the sides and weakens the floor.
I took 5/8" plywood and put two pieces 5" by 12" into the heat duct area and screwed the flooring to it and secured and strengthened the floor

[Bill and Ann]

Attaboy Sven