Rigid vs Flex Chimney Liner

[jaychino415]

Thoughts from people who used or install them? Trying to decide which one would be better. My situation, i have a CL bought Lopi Freedom insert, 17 foot tall exterior chimney with 8"x13" clay liner. I live on a hill and my neighbor's house is higher in elevation than my house. We are separated by 10 feet. Any advice welcome. Thx.

 

[bholler]

Both are fine flex is way easier to install and if you get heavy wall flex it is just as durable. Neither will do anything to change the potential problem of your neighbors house being that close though

 

[begreen]

Sounds like it could be a serious issue if the neighbors house is downwind. What direction do the prevailing winter winds blow?

Invite your neighbor over to enjoy some fireside warmth and send them home with a couple nice bottles of wine.

 

[jaychino415]

Sounds like it could be a serious issue if the neighbors house is downwind. What direction do the prevailing winter winds blow?

Invite your neighbor over to enjoy some fireside warmth and send them home with a couple nice bottles of wine.

The wind blows from their house to my house. Maybe an addition of 3 feet rigid pipe to flex liner above chimney might help?

 

[bholler]

Maybe an addition of 3 feet rigid pipe to flex liner above chimney might help?

You would have to add a section of insulated class a chimney to the top if you just use bare pipe it will cause lots of problems with creosote buildup. And what ever liner you choose make sure you insulate it

 

[jaychino415]

You would have to add a section of insulated class a chimney to the top if you just use bare pipe it will cause lots of problems with creosote buildup. And what ever liner you choose make sure you insulate it

Thanks Bholler for the advice. Probably will go with the flex liner kit from Chimney Liner Depot unless there are any other suggestions.

 

[bholler]

I always recommend heavy wall flex liner over light wall i think it is worth the extra money but light wall will work if you dont want to pay the extra

 

[spirilis]

Only thing I have to offer is 20ft of insulated rigid drafts like a bat out of hell!

 

[bholler]

Only thing I have to offer is 20ft of insulated rigid drafts like a bat out of hell!

It drafts no different than heavy wall flex and not much different than light wall really the only benifit is more durability over light wall and it is slightly easier to clean than light wall. But pretty much the same as heavy wall in those respects

 

[Hogwildz]

We all know I am partial to double pre-insulated rigid. I have it, and I love it.
I have installed both, and found the rigid easier to install in my application with a 13 x 13 flue tile.
A few flexs I installed went fine, and just as many were tight, and had to be pulled, tugged, wrestled and spun to get them past some mortar globs and uneven tile seams.
Either will do just fine. If you can spring for the insulated double wall rigid, that's what I would do. Otherwise, save the dough and go with flex, but I would insulate the flex. And install a block off plate!

 

[jaychino415]

We all know I am partial to double pre-insulated rigid. I have it, and I love it.
I have installed both, and found the rigid easier to install in my application with a 13 x 13 flue tile.
A few flexs I installed went fine, and just as many were tight, and had to be pulled, tugged, wrestled and spun to get them past some mortar globs and uneven tie seams.
Either will do just fine. If you can spring for the insulated double wall rigid, that's what I would do. Otherwise, save the dough and go with flex, but I would insulate the flex. And install a block off plate!

How much dough are we talking about Hogwildz? The rigid probably cleans easier too?

 

[bholler]

I figured you would chime in hog. That seems like a good system i just dont like simpson personally so i dont use their stuff. But that is just my opinion many of their products are very good.

 

[bholler]

The rigid probably cleans easier too?

not noticeably especially the heavy wall flex but dura liner is preinsulated which is definitely a benefit especially on your 8x13

 

[Hogwildz]

Strictly my opinion, but the rigid has a few small advantages. It is truly smooth wall. So less nooks , crannies and grooves to collect junk. Some say the swirl in flex promoted flow, others say less resistance with the rigid smooth wall. I think the difference is prolly minute if any. As far as cleaning, again, truly smooth wall, less resistance, brush may make fuller contact, but again, difference prolly minute or non-existent.
I was at about 1k for my set up, from stove adapter to extended cap. Back when I installed mine, I compared the cost, and while flex was less expensive for the liner itself, even more so with a kit with cap etc. With the added cost of insulation, it was prolly about a couple hundred bucks or slight more for the double wall rigid. I did install myself, so wasn't that much a PITA.
With your flue tile size, it may even be slightly easier to install rigid in your rather than flex, cause if your insulating the flex, it will prolly be tight, and may get hung up on the mortar seams & any offset tiles.
You have time, search around and compare pricing.
I got mine off ventingpipe.com. There are other vendors out there. Even Walmart online sells some liner & class a products, through their outside vendors.

I do have 5' of flex at the bottom, from 1st old flue tile to stove outlet, and the rigid for me, is much easier and smoother to brush. Once the brush hits the flex, it takes some more force to get it through the flex. Not Rhino power force, but def noticeable.

I want to add, that wrestling with 20-30 foot of flex is not super enjoyable on a roof. This to me is where the rigid shined, only had to manage 4' sections at a time, and lower down as you go.
I have helped a few members over the years install flex, and I was usually the one on the roof that was trying to balance myself and wrangle a worm down the old flue. The worst is when it gets hung up halfway down. Spinning it sometimes works. But it really sucks when you have to pull it up, send it down, pull it up, several times. Makes for tires arms & back.

The last one was on a lift, that didn't fully reach the chimney. That was a challenge to say the least. But well worth the good feeling afterwards, of helping a brotha out.

 

[jaychino415]

Strictly my opinion, but the rigid has a few small advantages. It is truly smooth wall. So less nooks , crannies and grooves to collect junk. Some say the swirl in flex promoted flow, others say less resistance with the rigid smooth wall. I think the difference is prolly minute if any. As far as cleaning, again, truly smooth wall, less resistance, brush may make fuller contact, but again, difference prolly minute or non-existent.
I was at about 1k for my set up, from stove adapter to extended cap. Back when I installed mine, I compared the cost, and while flex was less expensive for the liner itself, even more so with a kit with cap etc. With the added cost of insulation, it was prolly about a couple hundred bucks or slight more for the double wall rigid. I did install myself, so wasn't that much a PITA.
With your flue tile size, it may even be slightly easier to install rigid in your rather than flex, cause if your insulating the flex, it will prolly be tight, and may get hung up on the mortar seams & any offset tiles.
You have time, search around and compare pricing.
I got mine off ventingpipe.com. There are other vendors out there. Even Walmart online sells some liner & class a products, through their outside vendors.

I do have 5' of flex at the bottom, from 1st old flue tile to stove outlet, and the rigid for me, is much easier and smoother to brush. Once the brush hits the flex, it takes some more force to get it through the flex. Not Rhino power force, but def noticeable.

I want to add, that wrestling with 20-30 foot of flex is not super enjoyable on a roof. This to me is where the rigid shined, only had to manage 4' sections at a time, and lower down as you go.
I have helped a few members over the years install flex, and I was usually the one on the roof that was trying to balance myself and wrangle a worm down the old flue. The worst is when it gets hung up halfway down. Spinning it sometimes works. But it really sucks when you have to pull it up, send it down, pull it up, several times. Makes for tires arms & back.

The last one was on a lift, that didn't fully reach the chimney. That was a challenge to say the least. But well worth the good feeling afterwards, of helping a brotha out.

Thanks for your input. I think i will double check my clay liner for size and send my bubble wrapped camcorder down the chimney to see what i am going to come up against. I think my smoke shelf is offset like many others by a few bricks and metal frame of damper. I love to demo, so it should be fun to rip it out.

 

[jeffesonm]

Much the same experience and opinions as Hogwildz. I installed 16' of rigid DuraLiner in my chimney and it was a breeze. I believe the flue was 12x8 but it was definitely a straight shot. I like how solid and strong the liner was... and like the insulation encapsulated within it. It cost a bit more than flex but not by too much given how relatively short my chimney is.

I also put in a 20' 5" flex liner when I replaced my oil furnace. This went into an 8x8 flue and I found the install generally more difficult. It is cumbersome manipulate a 20' metal tube standing on your roof, and even with the pull cone it was more difficult to get down.

I ended up cutting my metal damper with a sawzall and a Diablo demo blade... went surprisingly quickly.

 

[Hogwildz]

Thanks for your input. I think i will double check my clay liner for size and send my bubble wrapped camcorder down the chimney to see what i am going to come up against. I think my smoke shelf is offset like many others by a few bricks and metal frame of damper. I love to demo, so it should be fun to rip it out.

I would say a majority of dampers and some smoke shelf demo is done on most liner installs. Yes, it is fun. Be prepared top get real dirty, a few cuts & nicks, and def wear eye protection & dust mask.

 

[jaychino415]

I would say a majority of dampers and some smoke shelf demo is done on most liner installs. Yes, it is fun. Be prepared top get real dirty, a few cuts & nicks, and def wear eye protection & dust mask.

Can't wait. Thanks for the advice Hogwildz. I will have the chimney cleaned by a sweep first and chisel out the bricks at their mortar joints to reduce the dust. Will keep the shopvac close by to remove any dust and debris. Then, take a sawsall with diablo blades to take apart of damper frame and damper out. I hope it won't take me all day. Wish me luck. Most of the sweeps in my area are really busy, but will post as progress as get going. Hopefully, the sooner the better.

 

[Hogwildz]

Have yourself an angle grinder ready also.

 

[jaychino415]

Have yourself an angle grinder ready also.

Gotcha. Just in case my blades don't make it passed first.

 

[bholler]

Can't wait. Thanks for the advice Hogwildz. I will have the chimney cleaned by a sweep first and chisel out the bricks at their mortar joints to reduce the dust. Will keep the shopvac close by to remove any dust and debris. Then, take a sawsall with diablo blades to take apart of damper frame and damper out. I hope it won't take me all day. Wish me luck. Most of the sweeps in my area are really busy, but will post as progress as get going. Hopefully, the sooner the better.

Take the frame out first it will make it allot easier and i prefer a grinder you just need to have someone hold a drop cloth over the opening to contain the sparks. Glad to see you are having it cleaned to that is one very important step many people miss

 

[jaychino415]

Take the frame out first it will make it allot easier and i prefer a grinder you just need to have someone hold a drop cloth over the opening to contain the sparks. Glad to see you are having it cleaned to that is one very important step many people miss

Thanks for advice Bholler. I have been lurking this forum for awhile and trying to learn as much as i can from experienced people who have done the installs before. I wonder how long does it take to do the demo and install. Has anyone timed themselves?

 

[LeoJr]

I bought from Chimney Liner Depot. They were surprisingly quick to deliver.

I opted for the middle thickness as I wanted to be able to sweep it with a degree of confidence that I wouldn't hurt it, and the thickest was really expensive.

I insulated mine even though it was being slid into existing double wall rigid.

The angle grinder makes for the cleanest cuts.

I did not like how the inner liner tended to unwrap at the ends. So I cut an inch of the non serrated part of a stainless hose clamp and used it as a backer plate. I drilled a hole through the liner and plate and then riveted them together. Most likely very unnecessary, but I felt better about it.

 

[bholler]

I wonder how long does it take to do the demo and install. Has anyone timed themselves?

If every thing goes as planned we can be done with an insert install in 3 to 4 hours but i also do 60 to 70 liners a year so i am sure it will take you longer. And there are also liners that dont go as planned we have had a few take 3 days but on average i would say 4 to 5 hours for us. For a first timer i would say on a straight forward install a day should be enough

 

[bholler]

I opted for the middle thickness as I wanted to be able to sweep it with a degree of confidence that I wouldn't hurt it, and the thickest was really expensive.
I insulated mine even though it was being slid into existing double wall rigid.
The angle grinder makes for the cleanest cuts.
I did not like how the inner liner tended to unwrap at the ends. So I cut an inch of the non serrated part of a stainless hose clamp and used it as a backer plate. I drilled a hole through the liner and plate and then riveted them together. Most likely very unnecessary, but I felt better about it.

Which type liner are you referring to was it single layer or double layer? If it was the single layer mid weight stuff the first few of that type we got from olympia started to unravel as well and they told us to put a rivet in spanning the seam before we cut and it would solve the problem. They have since than replaced the machine they are making the mid weight that they call hybrid and it is no longer a problem but if anyone has one start to unravel a rivet will fix the problem.