Suggestions needed to feed a rigid tube liner above the roof with a flat concrete top.

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Not sure what the measurements of the rivets refer to.
e.g.
4 x 16 mm. steel

16mm length I assume.
4mm diameter head or thickness of the rivet itself?
 
Typically the first number is the diameter (size of hole you need) and the second number is the "grip" or maximum thickness of material it can join.

For a chimney liner I would probably go with a 1/8" (~4 mm) diameter and grip of 1/8 or 1/4" (4-8 mm). I suppose it doesn't matter too much if you go a little bigger, but you may need a beefier tool.
 
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Typically the first number is the diameter (size of hole you need) and the second number is the "grip" or maximum thickness of material it can join.

For a chimney liner I would probably go with a 1/8" (~4 mm) diameter and grip of 1/8 or 1/4" (4-8 mm). I suppose it doesn't matter too much if you go a little bigger, but you may need a beefier tool.
Perfect thanks. Was just looking it up here;

So a 4mm drill bit is needed.
 
I misspoke, you will need a hole slightly larger than the rivet diameter. The page you found is good.
 
I misspoke, you will need a hole slightly larger than the rivet diameter. The page you found is good.


Great revised plan:

Wrap each metre section with rock wool (50mm) with aluminium covering for ease of handling.
Rivet each join with 4mm rivets.
I'll fabricate a clamp and support at the lower portion to help with the weight.
 
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What would be the best way to hold the rock wool wrap around the liner? Would duck tape be ok (thinking that the outside of the wool will be fairly cool) or some kind of twisted wire?
 
That's great that you have a plan to insulate the liner. You will enjoy the performance boost from insulation.

Wrapping rockwool around a pipe can be tricky because it likes to tear and crumble, at least that's my experience with the stuff we have here. I'm sure you'll figure out good technique.

A wire wrap / mesh is a good idea to keep it from catching on the bricks as it goes up. Do you have foil tape available? That would be another option. I wouldn't use duct tape just because you can't guarantee it wouldn't melt.
 
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That's great that you have a plan to insulate the liner. You will enjoy the performance boost from insulation.

Wrapping rockwool around a pipe can be tricky because it likes to tear and crumble, at least that's my experience with the stuff we have here. I'm sure you'll figure out good technique.

A wire wrap / mesh is a good idea to keep it from catching on the bricks as it goes up. Do you have foil tape available? That would be another option. I wouldn't use duct tape just because you can't guarantee it wouldn't melt.


Thanks yes worth doing properly. I know the installers would not do this at all. Only on the part exposed to the outside air.

Looking at this wool, actually covered in an alumium wrap to avoid crumbling. A bit more pricey but worth it I think.
I'll have a look for foil tape or ask the seller.


here we go:

 
Ok great that will be easier. That stuff may still be hard to wrap though because it's so thick. For reference, chimney liner blankets here are typically about 1/2" to at most 1" (1 - 2 cm) thickness. So in a way that stuff would be overkill. However it won't hurt as long as you can wrap it.
 
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I have an idea. Are those panels faced with foil on both sides? If so, take a long serrated knife and carefully slice them in half so you get 2 pieces of 2.5cm insulation faced on one side. Then wrap it around the pipe, foil side out, and tape the seam with foil tape. That should hold nicely. Then after you rivet the sections together, slide it up and over the rivets and tape the seam where it meets the previous section.
 
Ok great that will be easier. That stuff may still be hard to wrap though because it's so thick. For reference, chimney liner blankets here are typically about 1/2" to at most 1" (1 - 2 cm) thickness. So in a way that stuff would be overkill. However it won't hurt as long as you can wrap it.

Ok good to know. I'll see how manageable it is and if a cm or 2 can be sliced off.
 
As a self reporting spoiled American who is just used to being able to buy anything I want online I found this thread very refreshing and educational. Making something work with what you have access to is an important skill lots of us don't have anymore. I am trying to teach this to my kids...who knows if they are listening lol.. Great project and I enjoyed following the progress. I hope it works out well!
 
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As a self reporting spoiled American who is just used to being able to buy anything I want online I found this thread very refreshing and educational. Making something work with what you have access to is an important skill lots of us don't have anymore. I am trying to traxj this to my kids...who knows if they are listening lol.. Great project and I enjoyed following the progress. I hope it works out well!

Many thanks.
I'm an expat from the UK so spoiled there also. I struggle here to find parts I would normally take for granted getting easily from the local hardware store.
I do have to invent and modify things often to build to a better standard.
 
Now we're talking! This will work well. If you can find a foil faced version, even better.

So a much better option? Worth the extra $$$?
I could always buy several rolls of tape and wrap them myself.
I have a 13cm liner so not too wide.

12mm or 25mm? Getting pricey.
I hope the 12mm will suffice
 
So a much better option? Worth the extra $$$?
I could always buy several rolls of tape and wrap them myself.
I have a 13cm liner so not too wide.
I think the ceramic fiber will be easier to work with than the rockwool. It can still tear if you try to stretch or fold it though.

So yes, if it were me I would buy that. I don't have a clear sense of the cost difference. You'd need what, 2 rolls to do the whole liner? Maybe 3?

Edit: now I see the dimensions, 14 meters by 61 cm, you could get a single layer around the whole liner with 1 roll. Worth it.
 
12mm thickness ok? I guess the flexible liners have just a thin amount.

Looks like the circumference will be 408mm (130mm diameter.)

rolls 0.61m wide.

I believe they can sell by the metre. Just 5 metres of liner I need to cover as the last metre will be outside and with a sleeve and other rockwool bits.

So I'd need
5 / 0.61 = 8.2
8.2 metres to cover the 5 metres .

price is 770 pesos m2.
8.2 * 0.61 = 5 m2
5m2 * 770 = 3850 pesos.

If my math is right. Maybe I'll get my 10yr old to check it;lol
 
Oh I thought the price was per roll not per m2. Whoops. So it's a little more expensive than I thought, but still cheap compared to what you'd pay here for it.

Yeah, a single 1/2" layer is enough. With such a large temperature differential between inside and outside, even adding a R=1 makes an enormous difference in the heat retention and stack temperature. Of course if you've got cash to burn, you could add another layer...
 
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It's a shame the ceramic fibre does not come with an outer layer.

I prefer the wraps with that aluminium layer (rock wool in this case) for ease of handling and wrapping. Although the thickness puts me off.

About 4.5 mts up there are some protruding metal bar stubs where I grinded the bars off. Sticking out maybe 0.5-1cm. Flue is 30cmx30cm.

The ceramic fibre will catch on this easily. The rock wool also but maybe less with the layer.

Decisions decisions!
 
Yep looks that way now.

I would like to thank you for all your advice. Really cleared some areas up for me where I was struggling.

Now just got to design the supports/clamps. I'd like to have one just between the main 0.5m black stove pipe and where the liner starts. I'll be choosing the rear exit pipe on the stove (have both options).

1 curved 90 degree bend at the rear (has a removable plate for cleaning) and then attached to the thick 2mm black stove pipe, which will just go through my closure plate and then have the liner start there. So will have some extra support just above the closure plate (which I'll make removable).

That's the plan anyway.

Possibly some strong brackets on the wall with a 130+mm jubilee clip or home made clamp from some 23cm galvanized piping I have leftover.
Jubilee clip holding some L shaped supports around the pipe that will rest on a couple of strong shelf brackets attached to the wall. Have that kind of design in my mind.
 
The seller just informed me he has the ceramic cloth to cover the fibre, 1/16.

But that gets too pricey. 1174 pesos per metre!!
Normally the insulation would get encased in a stainless steel mesh sleeve that protects it and keeps it intact.
 
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