breeze

Single leaf breeze (not supporting). I dug a 100sq test hole in the ctr and found conc. below the screed so I figure using conc. blocks will be ok. Do internal walls require a dpc? I'm assuming it would be good practice to dig out a channel in the screed and block up off the concrete below...

Would a £70 Erbauer reciprocating saw be ok for cutting out a doorway in a single leaf internal breeze wall, using masonry blades? The masonry blades aren't free but I won't have cutting discs in the house, they're banned. Not a supporting wall. Thanks Dain