help please

skinnycrow

Hello, I am going to install a solid fuel range in our new build. I am wondering what the best method for passing the flue through the cavity wall. The wall is a concrete block with a 150mm cavity. What is the best way to ensure that the bonded bead insulation is protected from the heat of the flue pipe? Is a double skinned flue pipe enough or can anybody tell me the best method of insulating the flue pipe.

Thanks in advance,

Michael..

Poor Uncle Tom

For a new build, it would be good building practice to build the chimney full height for the flue pipe, not just out through the cavity wall.

skinnycrow

Thanks Uncle Tom, the chimney does go the full height but goes up the outside wall if you now what I mean. I need to pass through the wall to join the chimney to the range.

Michael..

Poor Uncle Tom

Sorry, I'm confused, is it the chimney or the flue pipe is going up the outside of the wall?

skinnycrow

Sorry for the confusion, the chimney is a block built chimney on the outside of the house. I need to pass through the wall to connect up to the chimney. Hope that makes sense.

Michael...

Poor Uncle Tom

skinnycrow wrote: »

Hello, I am going to install a solid fuel range in our new build. I am wondering what the best method for passing the flue through the cavity wall.

skinnycrow wrote: »

the chimney is a block built chimney on the outside of the house. I need to pass through the wall to connect up to the chimney....

OK, so the chimney was built for a normal fireback and the throat piece is too low for the flue pipe so it has to break out at a higher level and meet the chimney?
If so, double check that it is a cavity wall you are passing through, as the cavity wall would normally follow around outside the chimney.

Anyway, If you are passing through the cavity wall it is probably best done by coreing or breaking through big enough to line the break through with a flue pipe and seal back against it. The flue liner for the stove/cooker/oven/fire can then be carried inside the flue pipe. This is necessary as the flue liner is not permanent and will need to be changed after 10 or 15 years.

The insulation in the cavity can be cleared back from the opening and filled out with an intumescent foam before fitting the flue pipe.

skinnycrow

Thanks for the info, flue liner seems like the way to go. What could you use to seal the gap between the clay liner and the range flue pipe?

Michael..

Poor Uncle Tom

It would depend on the space around the liner whether you use an intumescent grout or an intumescent foam to fill.