304 SS Liner? Insulation Required?

[jtp10181]

OK I am trying to organize / standardize how we do our wood re-line installations and am looking at the Simpson DuraFlex and DuraLiner catalogs. I always see on here people talking about 316Ti liners. Most of the stuff Simpson offers is 304 SS. So... opinions?

Also, along the same lines, it says in here that in order to get 0" clearance to masonry you NEED to use the insulation sleeve on the flex stuff. I assume this is because its known that most masonry flues do not have the proper clearances around them. There are also spacers available that force the liner to keep a 1" clearance, I am assuming this is for people who don't want to insulate? What happens if the flue is too small to get a liner + insulation (or spacers) down it? Customer is SOL?

FYI I want to use the Simpson product because that's what our distribution center stocks. Using any other product creates longer leads times and we cannot easily return unused product.

 

[BrotherBart]

The Duraflex is 316ti. I installed one into my main flue last week. Let your installers look at a piece of it before you commit. It is one of the stiffest flex liners out there and if you have a flue with offsets you can pretty much forget it. There are only five corregations between each seem. I wanted it as stiff as I could get so it worked fine for me. That picture in their manual showing a 90 degree turn into a thimble is a cruel joke. It ain't gonna do it without crushing the liner. I did it with another brand on my basement installation but the Duraflex would not have made the bend.

I didn't insulate because I don't have room for the insulation or the standoffs but it is only required if there isn't a 1" clearance between the masonry and the combustibles and I have that. But I did pack the upper five feet of the chimney with rockwool.



Just thought you needed to know about the stiffness factor.

 

[jtp10181]

The "DuraFlex" is available in 304SS or 316Ti. I just worked with some today, helping out an installer. It was part of a kit that is not even in their catalog, I assume it is 304SS but I will have to double check. It was fairly flexible, as it came wound up in a ball. It was like fighting a 15' snake trying to make it straight though. We needed to ovalize a section to get it through the damper and it was pretty easy to do that with a 2x6 and some body weight. Anyway... regardless, I am still interested in the deal with the 304SS. All the "DuraLiner" is stated to be 304SS, and I don't see any 316Ti available.

 

[elkimmeg]

In order to comply with UL1777 listing 1/2" insulation is required Ul 1777 is esentually compliance to clearance issues. what is happening here is I selling you a lesser grade ss304 but ti use it it has to be ul1777 to equal durability and protection of a higher grade SS like 316 TI Plain 304 grade may not satisy durability requirements without insulation


Ther are two issues durability and clearance issues


It is my interpetation if the chimney complies to NFPA 211 standards and is in decent repair then UL 1777 in not needed for clearance issues when using 316ti the 316 ti solves the durability issue Now if liners are cracked motar joints missing motar bi ricks need re pointing or re setting or clearance issue are suspect 1/2" insulation is required because the chimney condition does not meet Nfpa 211 standards All unlined chimneys require full UL 1777 compliance / 1/2" insulation is required We are a only talking about linning masonry chimneys not metal pre fabs

 

[jtp10181]

Yeah I know pre-fabs is a whole other beast. That has to be insulated no matter what.

It doesn't specify different requirements from the 304 to the 316Ti, it seems to say you always have to insulate the flex liners. Maybe it is under the assumption you are re-lining the shimney because it does not meet code in the first place. If the chimney is a code compliant many people would just stub a liner up and call it good.

So if we are working with a customer and we try to "upsell" them to the 316Ti liner, basically its just going to be more durable and last longer. What kind of life span are we talking about for the 304 vs the 316Ti?

 

[elkimmeg]

JTP in the old forum there was a discussion that went on for days At that time I had code refferences that only allowed 316ti liners but 304 cheaper liners were being used so I looked into the issue and found, that with the 304 liner it was required to be insulated to meet ul1777. Once it met Ul 1777 it was a tested and allowed use. It does not meet UL 1777 without insulation

confusing the issue is another UL standard UL 103ht the 304 did not meet that standard without insulation but the 316ti did without insulation The thid factor is clearance to combustiables and chimney condition. From that discussion, was the chimney in decent shape and proper masonry thickness protected the combustiables, then only UL 103ht was needed

UL 1777 not needed becauce of NFPA 211 compliance If the chimney is in bad repair cracked flue liners ect
then as a cost saver insulated 304 liner UL 1777 can be used as well as better grades ss but the insulation is mandatory

This reminds me Maybe I should post what goes into NFPA I and 2 chimney inspection proceedures. While at it, the codes concerning the requirement for the inspections and cleanings prior to installations

Here is one in the did you know category, there is actual code language requiring yearly cleanings I have some residents submit cleaning reports that get stamped into public records.

Did you also know the stoves have to be installed to NFPA compliance and part of that compliance is adhereing to the whole body of code. meaning not providing or not cleaning your chimney viods the compliance which viods the warranty. I don't know how that gets regulated by DIYers Coide also call for a NFPA compliant Chimeny inspection by a certified inspector but does not have language identifying a certifid inspector or who is qualified to preform the inspection Me I talk to the homeowner and if the chimney is less that 10/12 years old and has seen little usage I wave the inspection report but not the cleaning unless it has be never used or the once /twice little usage I can usually tell doing the inspction whether I will require a cleaning or inspection as well if one slips by the paperwork process of permitting