Thanks for your replies, so thunderbolts,http://www.tradefixdirect.com/nails-screws-fixings/fixings/anchor-bolts/thunderbolts/thunderbolts-hexagon-head-galvanised these things will provide a better fixing than resin?
Just found a chimney stack 300mm wide in the bedroom that is cut off just above floorboards, nothing supporting it, the stack has been cut off in the adjacent room and gallows in the loft, planning to install 2 gallows on this 300mm at the same level as the existing gallows.
I know SE! But its like the size of a ruler and theres at least double the amount of brickwork below then there is above the roof.
Bricks are in good condition, 6mm thick gallows and 5mm plate up against brickwork with 2:6 mortar bed. Type c1 from gallowbrackets.com
Always used resin and studs for serious fixing, was going to install m12 stud 85mm in to solid brickwork, stack is alredy rendered and looking solid, no issues with party wall. Stack is built into the party wall and is double leaf solid. Have seen thunderbolts but im not so interested in the tensile strength of the bolts was going to get grade 8.8 from local fixing supplier, more interested in actual grit of the fixing, bricks are only what 7kn compressive, i know different force all together! The bricks would fail before the fixings, should have explained fully from the start apologies!
Crap phone keyboard hence text talk!