What is this under our lino!?

[Dontpeemeoff]

We currently have really crappy Lino in our kitchen. I had a look at what is beneath and it’s some plasticky tiles and the then under that I can’t really tell!
does anyone know what this could be from the pic?
For reference our house is a Victorian terrace.
Looks like concrete with loads of glue maybe?

Be careful the old plasticky tiles aren’t asbestos containing thermoplastic floor tiles. Did you test them?

Surely it is something like Marley tiles. The glue was laid first and the tiles put on top. That is what I used to have in my kitchen years ago. My house was built in the 1970s. I have since had them up and the floor levelled.
Edited to say that my floors all all concrete at the bottom.

I did think this AFTER I had a look 😬 I’ll look into testing

If you mean the stuff with diagonal lines, it's probably glue remaining after old 1960's tiles were pulled up. A Victorian concrete floor is probably damp. If one day you have money to spare, you could have it dug up, and a new floor laid to modern standards, with a DPM and ventilation.

Victorian kitchen floors usually have pipes under them. Lead pipes usually leak after a hundred years. Iron pipes usually leak after 60 years. So don't spend much money on the floor until you replace the pipes. There is probably a glazed clay gulley outside the kitchen wall, where the sink used to be, which is pretty sure to be cracked or broken and leaking. You can look at it to see if it has been replaced with plastic. If the ground around it has sunk, or the concrete cracked, or the gulley sunk, or tilted, it is still leaking and needs to be dug out. These are all surprisingly simple building jobs. Plumbers don't like them because they have petal soft hands unsuited to digging holes.

@PigletJohn i think in an ideal world we would lay some tiles down. Idk about a leak but I guess it could be looked into when we lay new flooring?

Before.