does welding subtract from structural integrity?

[twistedblack69]

Got a leak in the car, and the drivers footwell has been sat wet for a week or so, am planning on taking all the carpets out, gettin 'em cleaned etc next week, but am worried that it may have started rotting the floor pans. In this case, if I were to get the floor pans welded, would this leave the chassis particularly weaker than before (before rot/rust)? As far as I'm aware, its too reinforce the chassis, right

[danny_p]

no.


if you weld up the seams on a car the chassi gets a hell of a lot stiffer

[VW BUSH]

Welding will alter the structure of the Steel in the region of the Weld.
This is called the heat affected zone.
Where a large area has been super heated  you will soften the steel and cause it to lose some of its properties.
This is not an issue when welding in floor pans etc but may be an issue on torsional and structural beams etc