I welded a couple of pieces of square tubing between the frame cross members. Originally thought that it was rot but just turned out to be the weak floor design and the previous owners were on the heavy side.
I too have added some metal cross members at the door area on my two trailers... I always think the floor in this area gets a lot of moisture from opening and closing the doors..
My POPUP trailer definitely got a soft floor in this area...
__________________ Roy and Carolyn
I claim Horse Creek Country in Southern Ill - Momabear is from North Texas
We live in King George VA RETIRED DOD DOAF DON CONTRACTOR Electronics Tech 42YRS
"We're burning daylight" - John Wayne
2008 STARCRAFT 14RT OFF-ROAD POPUP with PD9260C and three 85AH 12VDC batteries
2010 F150 FX4 5.4 GAS with 3.73 gears - Super Cab - Towing Package - 2KW Honda EU2000i Gen
K9PHT (since 1957) 146.52Mhz
"We always have a PLAN B"