Chimney rebuild

Roky2018

hi,

I knocking down the chimney due to damp on chimney breast in bedroom. While removing noticed around the chimney pots was installed sand and its all moist. Flashing was perfect,render ok, concrete blocks chimney was buit.(wasn’t any visible big crack or same thing)

My question is what should I install around the pots when new chimney going be built?

I know they installing new days vermiculite but is this keeps my pots in place? My chimney very high 2.5 metres.

bfclancy2

so what is the root cause for the damp in the bedroom, if the fill is damp then it was either getting in through the render or else most probably down from the top, why are you knocking the whole chimney if you haven't root caused it, after its rebuilt either fill with bags of vermicullite or dry sand, cement lime mix

monseiur

I would hazard a guess that the dampness is caused by water getting in at the back flashing, that is the lead flashing where the roof tiles meet the chimney (where the bucket is in your last photo) When rebuilding pay particular attention to this - you may have to remove a row or two of tiles to get it right.

Roky2018

flashing was grand, all moist was from middle chimney.render was perfect but inside blocks as you all damp. Chimney cap was good.

Roky2018

just wondering do vermiculite support a bit in place pots? (Like sand do) I be installing chimney tray just to be sure…

Roky2018

lime mix?

For bricks laying : lime, cement, sand 3:1?

The Continental Op

https://www.boards.ie/discussion/comment/122481661#Comment_122481661

Just mix it up with cement in place of sand.

https://www.vermiculite.org/wp-content/uploads/2014/10/Vermiculite-Concrete.pdf