Are these enclosure materials iffy?

[StellaDoore]

A friend of mine has is building a snake enclosure, 4x2x2 dimensions, built on top of a TV cabinet. He's made it out of concrete sheeting but that wasn't keeping the heat in, so he added a layer of styrofoam-type insulation. He's painted this over with pond-tight (i think is how you spell it...) for water-proofing and has installed a glass front.

I mentioned this to a reptile keeper working at the local pet shop (it specialises in fish and reptiles) who was a little concerned. Should he be? I haven't been building the cage so have done no research on it. My friend assures me that he researched it all and it all checks out, but I'm not convinced.

Please give me your opinions asap because he really wants to put a beautiful BHP in this thing, and I'm not sure if I'm comfortable with it yet.

Thanks everyone!

Some added info: the insulation is on the inside of the cage, the concrete sheeting is on the outside, he's used some sort of wood (can't remember what) as the frame.
Any opinions and discussion is greatly appreciated, I really don't want to kill this snake. He doesn't see any reason not to get this snake tonight or tomorrow, so if this enclosure is a danger, I need to know right away! I also can't find anything on building an enclosure with those materials, which makes me even more worried :S

 

[zan777]

Pondtite is vivarium safe as it is suitable for use with fish. If everything is sealed internally so that the only surface the animal can come in contact with is pondtite I wouldnt have a problem. If there is exposed insulation then there would be a problem IMO