Diy issue, help please

[IdoIdoIdoOoh]

I would say I'm competent at basic DIY tasks.. until I run into a problem.
I've just tried to put a shelf up which I've done a million times (never on this wall) and there's something in the wall thats stopping my drill go in enough to put the plug in.
It's a new build house with plasterboard walls, the wall I'm stuck on is hallway one side and kitchen the other. What is this that I've run into does anyone know and what do I do?
It feels rock hard and when I shone my torch in it is sort of yellow/cream in colour.
Any answers appreciated, can't call my dad until he's finished work.

Sounds like it’s a solid wall or maybe a joist? Although those should let you drill into it.

Could it be expanding foam applied round a pipe or something? Basically something you wouldn’t normally see there?

Are you using the right drill bit? I think you need a masonry drill bit. Make sure there are no water or gas pipes or electrical cables behind.

Is the yellow/cream coloured stuff cavity insulation or some kind insulation board?

Maybe wait for Dad. I consider myself a bit ( very good) of a diy'er too but in this case i would wait for my Dad too. Given it backs onto kitchen there could be pipe work there.

Probably needs a hammer drill

When you say plasterboard walls do you mean internal walls that are just plasterboard or dry lined ?

Dry lined walls ( usually external walls but sometimes internal as well) appear to be plasterboard but are not. They are big sheets of plasterboard that are ' dot and dab' ie small amounts of plaster on the corners and at intervals to stick it to the breeze block or the modern version. It leaves a small gap between so you think it's plasterboard but not. The new blocks are cream .

They are a bastard to work with