What type of internal wall have I got?!! Is it supparting?

[hawkish]

Hi everyone, Got a 1955 3 bed council type house in cheltenham - the type with the toilet in a seperate little room and the rest of the bathroom next door. The internal walls in this house are made of some weird grey stuff then plastered over. When drilled grey dust comes out freeley. and when exposed it dosent look solid enough to be a supporting. I cant find this stuff anywhere on the net and I am looking at making the bathroom into 1 room and removing the existing wall to replace with stud at the appropriate position. Had a look in the attic and the beams are not resting on the structure - seeing as it is next to the outside wall and it is not part of a bigger centeral wall and there is nothing downstairs underneath it. I am 99% confident that it can go without support but because it is more substantial than stud I am ****ting it that my house will fall over if i go ahead. !!!!
Any Ideas what this stuff is?

Thanks in advance

 

[noseall]

sounds like you have fly ash cinderblock to me. provided the wall does not carry on up into the loft space to take the weight of any roof beams, joists or ceiling binders, then you will probably be ok.

some internal walls do offer lateral restraint to adjacent walls but this generally applies to internal walls built from the ground floor up.