Chimney replacement - Block? Dbl wall steel? or s/st? – see pics.

[Drifthopper]

This spring or early summer the roof on the house needs to be replaced, Along with the roof replacement will be a chimney replacement for the wood burner.

See the pictures below of current block chimney. The outside ones were from last September, its worse now, the ones from in the garage were taken recently.

The few guys that I talked to say knock the block chimney out and replace it with pipe.
My WoodChuck Wood Furnace has a 8” flue, and is in the basement.
Flue goes out thru the basement concrete wall, up into the garage, and up and out thru the roof.

My concern is going thru the concrete wall with the new pipe / flue from the basement. Thru the wall then into a tee, up for the flue then below for the clean out..??

Then….what are my options for pipe? Double wall steel? Or go with stainless steel??

And then buying now….gezzz the stove shops around here are already selling gas grills and outdoor fireplaces….can i order off this site or off the internet?

Any insight is greatly appreciated.

 

[Drifthopper]

Any one with a similar situtation??

 

[Metal]

What are the inside dimensions of the block chimney? I would line the block chimney with a stainless liner if you can get one to fit.

 

[Todd]

Is that the paint cracking or the block? What does the clay flue tile look like inside? Looks like there are about 5 blocks on the roof and you could replace those along with the clay flue tiles much cheaper than a steel chimney. If the blocks and flue tiles are in good shape you could just dress it up with some new paint.

 

[Drifthopper]

The clay liner is 7 x 7 on the inside. When I got this wood furnace in Oct. with the 8” flue, draft was a concern, I had a post on here about it. In Nov. I just knocked out the crock thru the poured wall, it was 6” , slid an 8” pipe thru the concrete with no crock, and tried to fit it up to the clay flue as best as possible. I burned in it all winter and in preparing for this new chimney, I took the pipe out from the cellar wall and I have quite a bit of creosote build up, a considerable amount more with this furnace then in previous seasons when I just had the regular wood stove down there.

I don’t why these pics loaded up length wise, makes it difficult to read this topic.

If you look close at the pic of the chimney in the garage, the pic is dark, but even some of my blocks are cracked down there in the garage. I don’t know what the clay liner looks like. But in ’99, the previous owner let the mortar wear away from where the clay comes thru the top cap,,,there was a gap in there and water must of got down between the blocks and the liner, froze, and cracked the blocks. If I had a recent pic of what the exterior blocks looked like now, all the top ones are cracked quite a bit, and the pic of the ceiling and floor, the creosote is dripping out, dripping on the floor, and is leaking between the garage ceiling and roof. That’s why I’m leaning toward a total replacement with steel flue.
I’ll spend the money to make it safe, but going thru the concrete wall and garage floor may be a bit of a job, and lookin' for input on that.

 

[fraxinus]

Blocks absorb water and you get cracking, spalling, flaking when it freezes. Paint usually makes things worse because it cracks and tends to hold water. I think you're probably right about water running down between the block and flu tiles, then freezing. There are a couple of things you can do. From the roof line up, remove the block (leaving the tile in place) and replace with brick. There are also masonry products that contain fiberglass/polypropolene fibres that can be put on the outside of the block - this should be sufficient for the parts that are not directly exposed to the weather. Sealing may be necessary on the roof part. In any case, you'll need to reseal the gap between tiles and block or brick at the top.

 

[RonB]

Hi Drifthopper, A cast in place insulated flue liner seems to fit your application. It would strengthen the chimney, fill voids, and allow you to maintain your clean out in the basement. I had a similar chimney application in my house and used the Golden Flue company and am happy with their product. Here is a link: http://www.goldenflue.com/golden.html#The Cast-In-Place Liner

 

[berlin]

a cast in place flue liner would likely cost more than tearing down and rebuilding the same with block. i'd rebuild with block but use round, self-aligning flue tile. also don't paint the block once it gets outside, or use brick, also, extend it higher than it is currently. if you do it yourself rebuilding with block will be likely the least expensive option.

 

[RonB]

a cast in place flue liner would likely cost more than tearing down and rebuilding the same with block. i'd rebuild with block but use round, self-aligning flue tile. also don't paint the block once it gets outside, or use brick, also, extend it higher than it is currently. if you do it yourself rebuilding with block will be likely the least expensive option.

Cast in place not only strengthens current chimney but it also insulates--thus improving draft and reducing creosote build up. It would also be cast as the correct flue size diameter for your stove. True, it is not a DIY project. But it can be cost effective if you consider that you will have a new liner (correct size), strengthened chimney, and insulated--all within the same chimney blocks as before. It would be interesting to see the costs both ways.