Best way to line 200yr old chimney?

Ginger83

Hi,
We're having a wood burning stove put in shortly. The building is 200yrs old and has a huge open fire and chimney which I cleared out/unblocked. It was packed with twigs, birds nests, etc.

Would it be ok to drop a flexible flue line down through the chimney? If so would it have to be a twin wall one?

Also I read some people on about filling with vermiculite. Do I need to do this?

Thanks

Stove Fan

Ginger83 wrote: »

Hi,
We're having a wood burning stove put in shortly. The building is 200yrs old and has a huge open fire and chimney which I cleared out/unblocked. It was packed with twigs, birds nests, etc.

Would it be ok to drop a flexible flue line down through the chimney? If so would it have to be a twin wall one?

Also I read some people on about filling with vermiculite. Do I need to do this?

Thanks

Hi:) Yes definately line the chimney. The liner that is needed is either 316 grade or 904 grade. If burning a lot of coal go for the dearer 904 grade liner.
The liner is flexible and not rigid pipe but is two helicoal strips of stainless steel. It will either pull down or pull up the chimney. If doing it yourself make sure it's the right way up. Most have an arrow to show direction of installation. The rigid twin wall insulated pipe is used where there is no chimney.

As the chimney is large then I would backfill with vermiculite providing the closure plate can take the extra weight. Even If you could only do the first few feet it would stop the heat from the stove rising and transferring through the closure plate.

Stove Fan:)

insulation monkey

It would take 100 bags of vermiculite to back fill some old chimneys so this is not practical in many cases.
I used the rockwool sleves for an installation like this recently and they were expensive but easily installed and working fine. http://fluefactory.com/index.php?function=DISPPROD&CID=8019
There is another similar product called chimnawrap ( deep pockets advised)
How do you suggest removing a liner that is backfilled with vermiculite?
as many only last 5 years. I have been to a job where the liner is perished and sand\vermiculite used for backfill is now pouring into the liner, homeowner advised he used approx 50-60 bags to backfill! which is sitting on a register plate waiting to bury some poor unsuspecting chimney sweep.
Luckily my quote for new liner was considered too expensive

cnocbui

You can get 904 grade liners with 20 year Guarantees. Mine is a 904 grade liner with an inner skin of titanium alloy to combat corrosion.

If the inside of the chimney is stone and of a large cross section area, filling with vermiculite might, as pointed out, require a large volume of the stuff. If insulation is impractical, then a twin wall liner might be the way to go. Get a high quality one.