Ring shank nails

[Dave-sparks]

Please explain to me a plausible situation in which this would be possible. He is to use a 20mm nail, through 6mm plywood, into 18mm floorboards. There is no way the nail will project below the underside of the floorboard.

It's not uncommon to find the underside of a floorboard gouged out to accommodate a pipe, especially where diyers have been having a go.

 

[OJCar]

It's not uncommon to find the underside of a floorboard gouged out to accommodate a pipe, especially where Scottish Gas have been having a go.

FTFY

 

[dobbslc]

I used 20mm screws to fix down 5mm ply before laying my wood flooring.

 

[brightspark]

you can buy thin steel cover plates for cables or pipes notched in joists if there not over 25mm deep https://www.tlc-direct.co.uk/Produc...tExVOM9kcKzWxLufkpwxQ1W0zKafYvTBoCKaMQAvD_BwE these comply with regs

 

[Erie Fred]

With the Op's name, I figured he would plug weld it down......