I am installing a cassette stove on a wall with an external chimney. The builders opening can't be widened enough to accommodate the stove so I will put it n in front of the opening and built a false chimney breast. 

 

Some questions,

1 should I block up the old opening with blockwork. 

2 what should I use for the stove to liner connection. Do I just use ordinary stove pipe or twin wall or? 

3 I will make the breast out of metal studs and class 1 board. Do I need to cover the ceiling and back wall ( brick and plaster) that will be inside the breast with the board also? 

 

Thank you

All replies appreciated 

I'm not sure how you can connect into the existing chimney. I don't think horizontal runs are allowed/recommended so I think you have to  go back and up at 45 degrees which may put the connection above the lintel?

 

 

 

Is it a new house? What's the chimney liner made of. 

 

Our chimney uses 225mm pumice liners with a 45 degree bend at the bottom so it comes out of the wall at 45 degrees. To that we fitted a register plate (more like a funnel) then 150mm stove pipe to a floor standing stove. All this is within a block work recess so you only see the stove pipe dissappear vertically upwards. You can't see the register funnel unless you look up under the lintel.

 

Can the cassette stove be installed in plasterboard? I might be wrong but I think class 1 is intended to stop fire spread in the event of a fire not be subject to constant heat. 

 

I think you best get a HETAS approved installer involved.