I have some raised beds that are bordered by bricks, and with brickwork for paths. So I couldn’t without destroying a lot of courtyards, push irrigation underneath.

But I have worked out I could use under the house.

I wouldn’t trust irrigation pipe as far as I could throw it, but is this stuff, suitable for cold pressure pipes?
https://www.bunnings.co.nz/pws-16mm-x-5m-straight-length-polybutylene-pipe_p00295323

I’d get a plumber to take a feed from before our water filter, then run under the house with one t junction to feed two beds.

I have some other beds, one in the lawn....unsure if I could trench under that. And two more with courtyards but no under house access. I’d rather not go aerial, or surface mount.

Thoughts?