Flu lining questions in cob chimney

[David Angel]

Currently our chimney is open with no liner. I would like a 5kw WOOD BURNING STOVE (not multifuel) and have the following questions:

1. I believe a 10meter 6inch 316 grade liner is sufficient for 'wood only', but can it be easily cut down if it is too long, or does it have to be exactly the right size when ordering?

2. I would like to use the 'pot hanger' method of fitting and I understand I need to cap the chimney pot. Is the process as straightforward as hiring a cherry picker and pulling it down the chimney and then resting the hanger on the top of the pot?

3. I understand I need to make a blanking plate to go just above the stove to retain the heat. What material should I use for this? Do I need to put a vent of some sort in it? If so what size?

4. Do I need to get a flue pipe with or without a sweeping hatch?

5. To connect the stove to the liner, is it as simple as just cutting a hole in the closure plate and connecting the liner to the stove pipe?

Sorry for the long list of questions, but local quotes are about £1000 for this and I would like to try and do this myself. Thanks

 

[Mark]

Currently our chimney is open with no liner. I would like a 5kw WOOD BURNING STOVE (not multifuel) and have the following questions:

1. I believe a 10meter 6inch 316 grade liner is sufficient for 'wood only', but can it be easily cut down if it is too long, or does it have to be exactly the right size when ordering?

It cuts with a hacksaw - leaving sharp edges. the hanger will cover them at the top, you need a flexible liner to stove pipe adapter at the bottom. But why not just buy what you need. Prices ~ £18/£20 per m.

2. I would like to use the 'pot hanger' method of fitting and I understand I need to cap the chimney pot. Is the process as straightforward as hiring a cherry picker and pulling it down the chimney and then resting the hanger on the top of the pot?

You might not need a cherry picker. You can pull the liner up the chimney - keep it the correct way round - and fit the hanger at the top. depends on your roof/access. The liner can be tricky to manipulate from the top.but yes the hanger just sits on the pot. If your chimney is fairly straight then it should be easy to do it from below. You still need two people, one on the roof lets down a rope which is attached to the liner at the bottom and the liner is push/pulled upwards.

3. I understand I need to make a blanking plate to go just above the stove to retain the heat. What material should I use for this? Do I need to put a vent of some sort in it? If so what size?

the register plate isnt to retain heat - it should be a fire barrer in the event of a fire in the chimneyt and should also be strong enough to prevent anything (loose bricks/masonary) falling down the chimney and doing harm. Typically people use steel or fireproof board. If you are using a liner then no vent needed - if no liner then there needs to be some access to sweep the chimney.

4. Do I need to get a flue pipe with or without a sweeping hatch?

Is the stove you are looking at easy to sweep through the stove? I've tried wth the flue pipe with a door in and its a pain. Especially if the flexible liner is larger than the flue pipe.
I am going to fit a Y piece with an end cap to the end of my flexible liner.

5. To connect the stove to the liner, is it as simple as just cutting a hole in the closure plate and connecting the liner to the stove pipe?

You have the flue pipe connected to the stove, then the flue pipe to an adapter which connects to the flexy liner. These adapters can be bought either same size or reducing, so 6inch flue pipe to 6 inch liner or 6 inch liner to 5 inch or even 4 inch flue pipe.My flexy liner comes down through my register plate - means I can see the connection.

Sorry for the long list of questions, but local quotes are about £1000 for this and I would like to try and do this myself. Thanks

Thats exactly why I fitted my own. I dont know much about cob and if you need any extra protection. i have insulation around my flexy liner as far as I could get it - like glasswool in metalic foil tubes.

sweep the chimney first.

Before I did it I put a camera up the chimney to inspect it - just a cheap usb webcam together with a small torch fastened to the end of a set of rods. with extension cable back to my laptop.

 

[Anita]

Hi Dave, we are in the process of doing this ouselves at the moment. My OH is in the building trade so he does just about everything himself!

I have found a couple of web-sites that have really useful information and tell you what you need and how to fit the liner.

http://www.stovesonline.co.uk/lining_a_chimney.html

[/url]http://www.fluesystems.com - has a very good on-line "helpdesk" facility as well as all of the products you will need

http://cgi.ebay.co.uk/ws/eBayISAPI....ht be useful simply as a back-up. Good luck.

 

[David Angel]

Thanks for the above two pieces of feedback. I appreciate that.

The ebay link you sent shows the seller to be from http://www.fluestore.com. Prices are as follows:

- 10 met of 6inch Hetas approved £160
- Brown pot hanger with bird guard £59.90
- Adapter for flue to stove pipe £17.00
- Nose cone - £4.25
- Deliver £15.

Total £256.85! How can the fitters justify over £1000 for this plus pulling it down the chimney? The only thing left out is the fireproof register plate.

 

[Alastair]

Some thoughts for costing.

Fitters may pay as much for the flue parts as you can get them for.

They have to have acceptable access methods for working at height, and if this is a cherry picker it can cost £350 per day, and hiring one for a half day is difficult, I know, I tried, and it couldn't make it as it was held up on it's earlier job.

If they don't hire a cherry picker, it may have to be scaffolding.

If they choose to use ladders only, it's a significant risk working on a roof. Its a lot higher when you're up there than it looks from the ground.

Gravity has been available at full strength where ever I have worked, it is very effective and 100% reliable. Just try standing on a table, and keeping your legs straight and arms in, fall sideways for a free sample.

There will probably be two people, and they may be able to get it done in a half day, but some flues can take 2 days.

If you were to fall off the roof, how soon would you be back at work?

Oh, and installing a wood burner and/or a flue is a notifiable service which LABC want to know about. Registered installers can do this as part of the job, otherwise LABC will charge you a fee.

Anybody with a thatched roof would be uninsured unless everything was approved.

 

[David Angel]

I can hire a cherry picker for £80 for the day and my neighbour is also interested in lining his chimney so hopefully we can share the cost. I have a hipped roof so I would not fancy scaffolding. To be fare, I think the £1000 cost would also include making up a register plate from steel or asbesolux etc which I did not account for.

 

[Alastair]

The LABC approval will cost between £100 and £250, depending on where you are.