Stack and Fire Code

[Amber Gold]

I'm on the town fire deptartment and I was talking with my chief last night about what I was planning and what I'd need to do to meet fire codes. At the time he couldn't find the NFPA code he needed, but he recalled that under high heat applications the nearest cumbustible material has to be at least 2 times the pipe diameter or 3', he couldn't remember which, but would get back to me. It's not a problem meeting these requirements from the wall, but once you get into the roof structure (rafters, collar ties, etc.) it becomes an issue. I recall from when I put my wood stove in that if you use sheet metal or cement board and have a 1" air space you can cut this distance in half, but my chief wasn't sure if this is the case with high heat applications. What have people done to get around this, or have they not? I'd like things to be buy code for safety and insurance reasons, just not sure how I'd go about it. If it matters I have a 14" stack.

Thanks

[gmcooper]

Josh,

Good luck in trying to meet the fire codes for a wood fired evaporator. Each person with input will have a different interpitation of the rules. As one fireman we know put it, there is nothing to code with a single wall stack pipe for an evaporator going thru the roof with temps that can reach 1000 degrees.
Protecting the wood and any flamable material by using some type of heat shield an air space is always a good practice.

We are in the construction business and deal with code inforcement all the time. Lets just say that everyone of them we deal with has a different view than the others and many times two people from the same dept in the same town can not agree on what they feel meets code.
Do the best you can to make everything safe. Being a fireman you would have a good idea on what will work for you.
Mark

[briduhunt]

I just happen to be a local NY Code Officer and a have been for the last 26 years HVAC design engineer. The NY code calls for a "All fuel" pipe from 12inches inside the building or under the roof penitration to thru the roof and out at least 3' high from the roof penitration. You also need a "All Fuel" roof flashing and storm collar. All of these items can be purchased from any wood stove sales dealers. There are several different brand names that are avaliable and that meet the NY codes. If I am not mistaken most of the other states around us use the similar codes or very close to them. With the "All Fuel" pioe your clearences are smaller and the system is safer. The cost of this pipe and fittings are very high, but what does it cost to replace the shack, equipment or even a life?

Well thats my 2 cents
Brian

[hard maple]

briduhunt
do they even make a "all fuel" pipe ,roof flashing and storm collar for a 24" diameter stack size?

[Big maple]

That's what the roof jack is there for,to give you clearance and stack support. If you get something too close it will smoke for a long time before it will light on fire. If that hppens you got the wood way to close and you need to remove that piece and throw it in the fire box.

[jrthe3]

i did it last year first boil in the brand new sugar house caught the roof on fire got it out only miner damage it could of been alot wors luckly my helper seen it so the next day i got a 16" pice of stack slid it over my 12" stack made end caps and fill the gap with fermickulite made my own double wall i could not find a pice of 12" double wall never had another prod
that was with my 12" stack going through a 32" x 36" hole in my roof

[maple flats]

I made my own triple wall. My stack is 12", around that I have 16" and around that i have 20". The triple wall starts 2' below the cieling joists and goes up tight against the steel roofing. I made 2" spacers to hold the pipes together. This satisfied my local fire inspector. The trusses are 32" oc where the stack goes thru, all other struues are 24oc.

[Amber Gold]

Thanks for the information.

Maple flats, I was talking to Royal Maple last night and he said he had a roof jack made with sleeve with 2" greater diameter than his stack coming out of the bottom of it for his stack to slide into. This maintains an air space between the two pipes. I like your method as well. What did you use for spacers and how did you support the pipes to keep them attached to the roof?

[Jeff E]

I like the idea of 'layering' pipe to get the effect of a class A chimney. I think I will try and wrap the inner pipe, 14", with fiberglass insulation(R-11), roll a 18" pipe around it and snap it together. The insulation should create a uniform spacing, and I could fabricate a bottom cover that would act as a support as well. The top will butt up against the roof jack.

Save about 1200 bucks over a class A installation for a 6' section between the bottom of the joists and the roof line.

I am using the roof jack as a support the chimney, in fact it becomes part of the chimney as the sections below connect into the bottom, and I stack other pipe on top of jack. This way the wieght of the pipe above the jack is supported by the jack/roof and only the pipe below the jack is supported by the evaporator.

I use the oversize jacks to slip my steam hood stacks through, so I can raise the hoods easily, and those pipes don't have to get to far about the roof line and are light.
Any concerns with this?

[Russell Lampron]

I have an 8" pipe going through an 11" roof jack pipe. It has a collar that goes around the 8" pipe that covers the 11" pipe so that water doesn't leak in. Take a look at the pictures in my photobucket album. I also have pieces of left over metal roofing over the studs for the roof inside the sugar house.

There is a thread on here somewhere where the spacing and insulation issues were discussed. It was recommended that the pipes not be insulated but I don't remember why.

[Amber Gold]

Russ I looked at your pictures and I see what you mean.

I wouldn't use regular insulation. It won't burn, but it does melt. Ceramic blanket insulation may work, but I'm not sure on the temperature range of it. I have an insulation blanket in my wood stove and that doesn't burn, I'm guessing it's some form of ceramic, not sure though. The insulation would reduce the amount of heat leaving the stack which would be a good thing.

I spoke to my chief about using a sleeve pipe with 12" to the nearest combustible material from that and he was OK with it. So I'm in the clear.

Thanks

[WESTVIRGINIAMAPLER]

I have my trusses on 2' center and I have a 10" single walled stainless stack going between them and I have the exposed trusses and boards covered with ceramic blanket and I run stack temps around 1600.

[RileySugarbush]

I believe the problem with insulating the stack is it does too good a job, and the stack itself gets too hot. If you have a stainless stack, maybe you will be ok, but with steel stack material, insulating it will probably reduce it's life considerably, kind of like a plain steel grate can erode/oxidize quickly.

I have an 8" stack centered between 24oc rafters and up through a jack. Exposed wood on the roof deck and rafters is shielded with aluminum flashing. The important part is that there is a significant airspace behind the shield, so that the heat cannot transfer to the wood. What Brandon is doing should be fine too, (obviously, since his roof isn't on fire). The point isn't to keep the heat in the stack so much as to keep it off the structure.

[Jeff E]

I am getting it! Slow but sure...

Thats the best part of this site. All of your experience keeping me out of trouble!

I am seeing folks using single stack, with as little as 6" of clearance to a combustable, with a barrier in between, such as metal or insulation.

With a 14" stack, I will push the rafters out to 32" over the arch, giving me 8 inches of clearance. With either a insulation or metal barrier, I should be OK.

[forester1]

Having fire extinguishers on hand and maybe super soaker squirt guns would be good too.

[maple flats]

Amber Gold, I have my outer layers suspended from med weight chain off the trusses from 4 points. Each chain has a turnbuckel for adjustment. The outer 2 layers rest on solid steel rod slung from these chains and the rods are kept from spreading by a piece of punched flat stock to hold the 2 rods parallel and just over 12" spread (my stack is 12") The top of my outter stack layers are both cut to match the roof (peak mount) and the turn buckles are adjusted to hold these tight against the underside of the tin roof. Is this too confusing to follow? For spacers I took 2"-3" wide strap (tin scrap about 22-24 ga.), I bent it at 1/2", 2.5" and 3" in a 3.5 inch long piece. I pop riveted one of these at 0, 90, 180, 270 degrees on each end of each 2' piece. If i was doing it again I would have gotten each pipe made to order for each layer, as I did it I used 2-8" pipes snapped together to make a 16" and used 2-10" to make my 20" layer. Doing it this way does not give real round 16 and 20" pipes but it works good.

[Amber Gold]

I think having minimal air space is fine for the short term, but over time the ignition point of wood exposed to high heat is significantly reduced. This is one of the main requirement for maintaining air spaces and having non-combustible layers. I don't think having a metal shield, which is screwed directly to the rafters, collar ties, and etc. is the greatest method. Metal is a great conductor of heat and a good amount of the heat is still transferred to wood it is attached to. An air space would be required to prevent this.

maple flats. I think I get what you mean. You took your standard black and and 10 inch pipe, put two pieces together to double the diameter and then using a chain/cable with a turnbuckle attached to the bottom and the top attached to the roof, are able to hold them tight to the roof. Is this correct?

[SeanD]

This has been a very helpful thread. Thanks for the good questions and answers. I think I'm going to go with a roof jack set up like Russell's where the roof jack is over-sized with a collar for the rain. That will also give me some freedom to increase stack size down the road. Right now I've got a 6" stack. Think a 10" is right?

Russell, how do you hold your stack in place through the roof jack? Just spacers or does something help hold the stack up?

Also, there is a HUGE price difference between stainless steel and galvanized roof jacks. I know stainless is a lot prettier, but am I getting anything else for the money?

Sean

[maple flats]

ss lasts much longer

[tuckermtn]

Amber Gold- how did you fare in the tornado on Thursday? Sounds like Northwood/Deerfield, etc. area got hit pretty hard.

any other mapletraders get hit by the straight-line winds, etc...

best of luck...

tuckermtn

[Amber Gold]

Made out fine. My parents live across from Northwood Lake on Route 4 and the tornado went right by their house (1/4 to 1/2 mile away). Fortunately no damage. It did make a mess though.

Thanks for the concern.

Josh

[brookledge]

Sean
Go with stainless. Once the heat burns off the galv. coating the steel will begin to rust. If you plan on keeping it in place for more than a few years it will be worth it.
Keith

[sapman]

I came right through the storm area about 9pm Thursday on my way to Maine. The utility guys were sure working hard. Came back through this morning and was amazed at the devastation, localized as it was. Saw one house with the side torn off.

Tim