Simpson Dura-Vent Galvanized pipe - Rusting from the inside - See Pics

[Drifthopper]

Any of you guys had something similar happen...???

8" Triple wall , galvanized Simpson Dura-vent stack.
Installed in 2008.
Its a 20' stack, this is the top section.
I was up on the roof in Early fall, and seen that rust was bubbling up from underneath, I cleaned and wired brushed it, and painted it with Rust-oleum.
Just recently I was up there again,,, and the rust is getting worse.
And it appears to be cracking.
I know I'll have to replace this top / exposed section, but any idea as to why this happened..?

 

[Dakotas Dad]

What is the warranty? At this moment I am very glad I did the stainless version..

 

[jeff_t]

Condensation in the airspace?

I'd replace both exposed sections with stainless.

 

[Drifthopper]

5 yr warranty on the galvanized.
Yeah... i'll go S/St next time.

 

[Dakotas Dad]

5 years.. damn, like they planned it. I would try cleaning it up and repainting. The good thing is, it's kind of cosmetic, The innermost tube is the most important, and it's stainless..

 

[bholler]

yeah that is why we wont put in any galvanized even below roof

 

[begreen]

Is this DuraPlus or DuraTech?

 

[pma1123]

The simpson galvanized triple wall 25-30y/o stuff I removed this summer had rusted through the outermost walls in a hidden spot. I wound up cutting it out with a sawzall, noticed the rusted-through spot that allowed a swiss-cheese like heat shielding around the inner SS.
At that point I noticed the nearby lath in my closet ceiling were charred.

Suddenly the 'cost' of all that shiny new SS stuff I just bought didn't seem to matter anymore...

This corrosion was caused by deterioration in the exposed pipe above the roof, thus causing water issues which affected the piping below.
It was missed by myself, a home inspector, and a certified sweep. I was replacing the flue system only because my insurance company wanted a 'professional install'.

 

[Z33]

5 years.. damn, like they planned it. I would try cleaning it up and repainting. The good thing is, it's kind of cosmetic, The innermost tube is the most important, and it's stainless..

I agree... but you need to use some kind of rust inhibitor/converter spray. If you don't the rust will bubble right back through.

 

[bholler]

5 years.. damn, like they planned it. I would try cleaning it up and repainting. The good thing is, it's kind of cosmetic, The innermost tube is the most important, and it's stainless..

All of the layers are very important if any one of them is compromised heat transfer can be increased greatly and could easily start a house fir it needs replaced

 

[Drifthopper]

Bringing this old topic back to the top.........

Well, the rust has gotten worse, ( I'll take some recent pics and post them soon ) but this past winter, when my burning season was coming to an end, there were little puffs of smoke streaming out from the rusted area, so that rust area / seam is all the way thru.

Stack was installed in 2008, disappointing that the galvanized pipe only last 8 seasons.

Going to go with Stainless steel pipe this time.

Where is a good place to buy...?

 

[begreen]

Good to hear that you are replacing the pipe. Is this double-wall DuraTech pipe or triple-wall DuraPlus? The big box stores sell pipe, but it may not be a match. Often Menards has the best pricing if they are in your area for Selkirk.

If DuraTech, I've had good luck ordering from these folks. They used to be dynamitebuys.com.
(broken link removed to http://www.woodstovepro.com/store/Chimney-Pipe-Venting-Pipe/Wood-All-Fuel-Piping/6-inch/DuraTech-c155/)

 

[bholler]

If it is duraplus triple wall I would switch to double wall it is much better pipe. I prefer ventis or excel over simpson products but duratech will work fine as well. I have not been impressed with the selkirk stuff i have worked on but it would still be a big step up from the triple wall galvanized stuff you have

 

[begreen]

Do you or have you burned coal in a stove connected to this chimney?

 

[Lake Girl]

Why is the double wall outperforming the triple wall?

 

[bholler]

Why is the double wall outperforming the triple wall?

Because it has double the insulation which keeps internal temps up better which means less creosote buildup and less condensation. It is also sealed better which means less chance of moisture getting in between the layers of the chimney causing problems with corrosion and deterioration of the insulation. That and I have seen lots of bugs ect make nests in that air gap which can cause problems.

 

[Drifthopper]

I'll try to catch all the questions.....
I'll check my receipts, but i believe i have triple wall.
No coal, wood only.
Stack is 20' tall, (4 ) sections of 5' /60" .

I have a Woodchuck wood furnace in my basement, pipe goes out cellar wall, into garage, up thru roof.
Interior pipes/ sections appear to be fine - in good condition, just this seam / section that is above the roof is rusted.

Thanks for the links , places to buy..!! : )

i have a busy July, but want to replace this in August , early Sept.

 

[begreen]

Note that while I too prefer DuraTech to DuraPlus, changing from one to the other will require a full rebuild of the chimney system. DuraTech is 8" OD, DuraPlus is 10".

 

[bholler]

Note that while I too prefer DuraTech to DuraPlus, changing from one to another will require a full rebuild of the chimney system.

Yes you are absolutely right but I would bet that even though the other sections look ok there has been water getting in there deteriorating that middle wall and the insulation. But I also understand budget constraints

 

[Hogwildz]

I have Duraliner double wall rigid, 10 years old, and the galv outer shell is like the day I got it.

 

[Drifthopper]

Recent pic of rusted area.

#2 pic.

 

[gnatboy911]

I'm new to burning, but I got my pipe from Northline express. Www.northlineexpress.com. prices were great with free shipping over 120ish in sales (don't remember exact number)

Sent from my SM-G900V using Tapatalk

 

[Kristal Ayers]

long exposure of galvanized pipe to environment and poor ventilation can also cause rusting.. so i think it will be better if you scrub and sand the rusted areas and give them atleast 3 coatings of paint. The paint can be zinc-rich or cold galvanizing spray. Ensure that the area is dried before each coating..

 

[Drifthopper]

Kristal..... Welcome to the Forum..!
And.. Thanks for the reply.... but these sections of pipe are beyond just painting. I had smoke streaming out from that rusted area, so it must be rusted all the way thru , from interior wall to the exterior.

To the others... I will be looking at the retailers that were linked. Thank you. As posted... this will be my August / Sept. project.

 

[Dakotas Dad]

We got ours from Northern Tool. Very happy, price was good, shipping was free on 24 feet of Simpson Dura Plus 6".