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Hello All

I am about to embark on extending my ensuiute bathroom. To do this I
need to remove a part of a lathe and plaster wall (Not solid)
where the extension will come into the bedroom. My question is how
would I remove this part of wall leaving the end neat and solid ready
for the stud wall to be attached. The L&P wall is not load bearing.

Having determined the position of the end stud, score the plaster on
both sides with a stanley knife or old wood chisel guided with a
straight edge. Carefully chisel an 8" hole right through the wall
next to the stud, then cut along the edge of the stud with a cheap
hardpoint handsaw - don't apply too much pressure.