Chimney Cap Spark Arrester

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When I had spark arrestors in my caps they always clogged. Always a pain to deal with. What do they actually do except keep birds out? Do they really arrest sparks? Seems like a little spark could get through that mesh size anyway.
Yes they do stop larger sparks. When I had a shake roof, I was glad the spark screen was in place. For folks in dry areas like New Mexico and Arizona a spark screen can be a good idea.
 
When I had spark arrestors in my caps they always clogged. Always a pain to deal with. What do they actually do except keep birds out? Do they really arrest sparks? Seems like a little spark could get through that mesh size anyway.
An actual spark arrestor screen will help contain sparks in the event of a chimney fire and are required by regulations in some areas. But they are much smaller mesh and in most cases they do cause problems with clogging. The screen on most caps is not a spark arrestor just a screen to keep animals out.
 
DuraTech has a fairly fine mesh screen, like 1/4"? It is a listed spark arrestor. Ours stayed clean for years until I had some damp maple one season. Then it clogged up in a month.
 
Now we’re getting somewhere. Very rarely does the law require a screen. There are definitely times I would want one despite the likelihood of it clogging even if it’s not required. Shake roof, super dry trees near the home, recurring animal problems, etc.
 
DuraTech has a fairly fine mesh screen, like 1/4"? It is a listed spark arrestor. Ours stayed clean for years until I had some damp maple one season. Then it clogged up in a month.
Yeah 1/4" mesh would be a spark arrestor. Most companies offer it as an option. You are one of the few i have heard of that didnt have issues with screen that fine. Good to know it can be done lol.
 
It stayed clean enough for me to only clean the cap and chimney every other year, but I usually get less than a cup of dust when sweeping. Dry wood is the key.
 
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Thank you for the replies. This has turned into a spirited discussion. As far as codes go, there are no codes here. However normal codes and specifications will be followed.first and foremost for safety, and of course to keep my insurance agent happy. The screen is not required, however we have friends that did not have a screen initially, now they have it because they found dead bluebirds in their stove. Hey, that's our state bird.. I keep squirrels under control, but I could see them being a problem if my cap wasn't going to be 11 feet in the air, and I would rather install the screen now than later.... cleaning it will be another issue, I'll deal with that later.

I too thought it was odd for the inspector to go against the way the manufacturer intends. He is well known in this area, and performs a lot of installs for a major stove seller here, and apparently is a go to guy for inspections. I will keep my options open. He will do the inspection for $145.00 The size fencing this inspector is recommending is 2x1, he said 1x1 is ok too. I could see where anything small even 1/2 inch would clog sooner than later.
 
CA has a more lenient code (amazing eh), but an arrestor is required on every solid fuel appliance.

Must pass 3/8" spheres and block 1/2" spheres.
I'm not home now but will check to see. DuraTech's might be 3/8".
 
I don't have and never had a screen on my cap - but there was that one August a few years ago, when I was away from home for a couple weeks, and I got that frantic call from my wife about how to get these two #@$* bats out of the house....
 
I don't have and never had a screen on my cap - but there was that one August a few years ago, when I was away from home for a couple weeks, and I got that frantic call from my wife about how to get these two #@$* bats out of the house....

LOL, I was on a fishing trip a few years ago, end of January, 10 inches of snow on the ground, and got a call from my wife about a odd creature a little bigger than a mouse and acted like mighty mouse. I figured it had a be a mouse, but she had to get out of the house, grabbed the dog and drove 30 miles to an all night Walmart. Turned out to be a flying squirrel, I trapped it when I got home and got rid of it.
 
LOL, I was on a fishing trip a few years ago, end of January, 10 inches of snow on the ground, and got a call from my wife about a odd creature a little bigger than a mouse and acted like mighty mouse. I figured it had a be a mouse, but she had to get out of the house, grabbed the dog and drove 30 miles to an all night Walmart. Turned out to be a flying squirrel, I trapped it when I got home and got rid of it.

We have 2 chimneys, pretty sure they somehow found their way down the fireplace one - not sure how they would have gotten past the closed damper though.

I tried to direct her to where the badminton racquets were stashed away, but I think somehow her & my early teens daughter (a fine pair to be dealing with that situation) eventually got them chased out an open doorway.

That was our only episode of anything getting in or down our chimneys in 20 odd years.
 
Back to the original post, the inspector sent me a picture of what was obviously a creosote burnout. I would say someone wasn't maintaining their pipe. The thought of a burnout is terrifying. I figure if proper wood burning practices are followed, with regular inspections, it shouldn't be a problem and won't matter what side of the metal the screen is on. I prefer to keep things stock, so to say.
 
Back to the original post, the inspector sent me a picture of what was obviously a creosote burnout. I would say someone wasn't maintaining their pipe. The thought of a burnout is terrifying. I figure if proper wood burning practices are followed, with regular inspections, it shouldn't be a problem and won't matter what side of the metal the screen is on. I prefer to keep things stock, so to say.
I am not sure what a burnout has to do with the location or existence of a screen.
 
I am not sure what a burnout has to do with the location or existence of a screen.

I'm new to this, and I'm not really sure of what I don't know, if that makes sense..... but that was my thought also, what would a burnout have to do with the screen. I would think that burning seasoned wood and properly maintaining it would pretty much prevent burnouts like that. With my cap being so high off the roof, I'm going to have to sweep it from underneath, and if the screen is on the outside of the cap the sweep brush won't be able to clean it.

This whole situation seems odd, why would he make such a big deal out of something so minor.. I'm thinking I should look into other sources for an inspection.
 
I'm new to this, and I'm not really sure of what I don't know, if that makes sense..... but that was my thought also, what would a burnout have to do with the screen. I would think that burning seasoned wood and properly maintaining it would pretty much prevent burnouts like that. With my cap being so high off the roof, I'm going to have to sweep it from underneath, and if the screen is on the outside of the cap the sweep brush won't be able to clean it.

This whole situation seems odd, why would he make such a big deal out of something so minor.. I'm thinking I should look into other sources for an inspection.
By burn out do you mean a chimney fire or do you mean a burnt out liner? Not that either one is effected in any way by the screen i am just curious.
 
By burn out do you mean a chimney fire or do you mean a burnt out liner? Not that either one is effected in any way by the screen i am just curious.

I don't know, I'm just going by the picture sent to me. Thoughts?
 

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I don't know, I'm just going by the picture sent to me. Thoughts?
Yeah that was clearly a chimney fire. But it has nothing to do with the screen.
 
Seems like some sensationalism over something unrelated. I don't get it, I needed some feedback to show otherwise or to verify it.
 
... He will do the inspection for $145.00 The size fencing this inspector is recommending is 2x1, he said 1x1 is ok too. I could see where anything small even 1/2 inch would clog sooner than later.

2x1 or 1x1...inches? At that large size, I'd say the screen isn't doing a dang thing. An ember the size of a charcoal briquette could fit through that opening, and most any bird smaller than a chicken could, too.

Me personally, I would (and have on my install) opt for a cap without a screen if possible. You are on this forum, so hopefully you know about the importance of dry wood and cleaning the flue - so that essentially removes the issues of a chimney fire and the use of the screen to catch large embers. The only thing left would be the potential for it to naturally plug over time, and 11 feet off the roof is going to be a bit of a beast for regular cleaning. If you are going up to clean the flue from the top, I guess it is no big thing to clean the cap too. But if you plan to brush from the bottom, then going up top for the cap becomes a real hassle.

Might also double check with your ins. co - if they are insisting on a 'professional' inspection, then find out this joker told you to hack up the as designed system, they might invalidate the whole thing.
 
2x1 or 1x1...inches? At that large size, I'd say the screen isn't doing a dang thing. An ember the size of a charcoal briquette could fit through that opening, and most any bird smaller than a chicken could, too.

Me personally, I would (and have on my install) opt for a cap without a screen if possible. You are on this forum, so hopefully you know about the importance of dry wood and cleaning the flue - so that essentially removes the issues of a chimney fire and the use of the screen to catch large embers. The only thing left would be the potential for it to naturally plug over time, and 11 feet off the roof is going to be a bit of a beast for regular cleaning. If you are going up to clean the flue from the top, I guess it is no big thing to clean the cap too. But if you plan to brush from the bottom, then going up top for the cap becomes a real hassle.

Might also double check with your ins. co - if they are insisting on a 'professional' inspection, then find out this joker told you to hack up the as designed system, they might invalidate the whole thing.

I thought the same thing about the 2x1 screen size, the 1x1 seems ok to me, bluebird houses are made with 1 1/2" openings. I wouldn't mind trying it without a screen, but if I decide I need one, I really don't want to have to take it down to add it later. If this was only a few feet of chimney it would be different. I plan inspecting the pipe a couple times a year at minimum. So cleaning from the bottom of the pipe will be a real hassle, must be worse than I imagine it will be, but I don't think I have a lot of options other than going on the roof and taking the pipe apart. A neighbor is going to help install it. I'll have to deal with it and learn as I go. A good burn plan will be key. I have a good stash of seasoned wood, and a few dead trees ready to bring down. I won't burn pine or cedar in it.

The insurance agent angle is a good point to make, I've been going out of my way to make sure this gets signed off.

I know it will be worth it once I get it up and running!