I’m not sure if you’re getting confused with the terminology, nobody has mentioned push fit, they said press fit, which uses an expensive tool to press the fitting onto the pipe. They look similar to these: https://www.screwfix.com/p/conex-ba...vAvl_hRzweej-bFHPjgaAsHWEALw_wcB&gclsrc=aw.ds
Sorry yeah was some confusion.
Edit: why bother with that under the floor boards though, i see the point when on full view and going for that style of exposed pipe work.