Chimney Cap Required?

[AbeAinPa]

I've been lurking for a while and have finally purchased an insert, a Lopi Declaration, and hope to be joining the wood heating family soon. This is a great site, I've learned quite a lot and think I'm ready to begin my install. One thing I can't seem to find an answer to however concerns the use of a liner cap on a chimney with an existing cover. I am doing a full liner of about 21' up the center flue of a central chimney. The existing masonry chimney has a slate cover mounted over the three flues, the sides are open. In this situation is a liner cap still useful, or does the slate cover provide enough protection?

Thanks ---

 

[atvdave]

Welcome to Hearth.com

If you don't have a block-off plate installed above the insert to seal off the weather that will come down the chimney, then yes you will need one.

The liner cover plate will stop cool air from coming down the chimney flue and seep into your house. Also on windy days some smoke & CO2 may be pushed bock down the out side of the liner thats not sealed and into your home.

 

[AbeAinPa]

Thanks for the reply. Just to clarify, I do plan on using a block off plate at the bottom and a sealer plate at the top. My question concerns the need for a rain cap since my chimney has an existing slate "roof" over the threee flues.

 

[atvdave]

Sorry.. I mis-read the post..

No.. if the liner opening is covered from rain or snow then no.. However I would make sure there is a screen around the slate cover opening's too keep the birds, and other animals out when not in uses.

 

[Hogwildz]

I suggest doing a search on multi flue chimneys. If they are all the same level, the exhaust from one can end up going down another.
Not a good thing. The ones that are in use should be at different heights to prevent this. Otherwise one may end up down drafting exhaust from the other(s) back down into the home.

 

[atvdave]

One other thing also.... Creostoe may build up on the bottom of the slate cover and my be hard to remove. With a rain cap on the liner it will build up on the rain cap witch can be removed from the liner and cleaned more easily on the ground.

Just a thought.. It may not matter... as long as you burn dry wood.... ;-)

 

[AbeAinPa]

Thanks for the advice, much appreciated!

I checked out the thread on multi-flue chimneys (thanks for the tip), and it sound like that scenario applies to me. I have had smokiness downstairs while burning upstairs on occasion. Opening a window in the upstairs room helped with that. Because of the slate covering on my chimney I can't really go with multiple height flues, but I was wondering if dividers forcing the outside flues to vent to the side, leaving the main flue venting to the front and rear, might be a suitable solution. Thanks again.

 

[savageactor7]

We have a free standing stove with no chimney cap and never had a problem...some municipalities may require a spark screens.

I wanted a cap but the mason rebuilding our chimney just about flat out refused to put one on...it became a contentious issue. Truthfully I don't know jack about chimneys and only wanted a cap cause they looked cool.

 

[Seth]

My chimney cap blew off in high winds a couple weeks ago. I never got around to fixing it and, when snow came, I thought, "Eh, I'll get it in the spring." I read this post last night and thought, "Yeah, I'll be fine. Some guys never have a problem without one."

This morning I woke up to the wife screaming, cat going nuts, and a flying squirrel darting around the house. Got this picture of him right before he jumped at me.

 

[jadm]

My chimney cap blew off in high winds a couple weeks ago. I never got around to fixing it and, when snow came, I thought, "Eh, I'll get it in the spring." I read this post last night and thought, "Yeah, I'll be fine. Some guys never have a problem without one."

This morning I woke up to the wife screaming, cat going nuts, and a flying squirrel darting around the house. Got this picture of him right before he jumped at me.

What a cute little critter. I assume you don't burn at night? These animals sure are smart when it comes to finding shelter.

Hope all in your house have recovered.

 

[Seth]

My chimney cap blew off in high winds a couple weeks ago. I never got around to fixing it and, when snow came, I thought, "Eh, I'll get it in the spring." I read this post last night and thought, "Yeah, I'll be fine. Some guys never have a problem without one."

This morning I woke up to the wife screaming, cat going nuts, and a flying squirrel darting around the house. Got this picture of him right before he jumped at me.

What a cute little critter. I assume you don't burn at night? These animals sure are smart when it comes to finding shelter.

Hope all in your house have recovered.

Thanks, ya. Just some excitement. Still can't believe it though. Nearest tree or anything taller than the roof is at least 50' away. I guess these things sure can glide. We'll see if he comes back. Pretty sure I heard an owl that sounded awful hungry tonight.

 

[AbeAinPa]

That's funny,at least after the fact! We had a squirrel come down our chimney this past Summer and I guess couldn't get back out, ended up dying on the smoke shelf. Of course we didn't realize this until that awful smell and the inevitable bugs. That was a nasty week or so! Plan for that was to put screening around the inside top of my chimney.

What I have up top there is two pieces of slate held up by six columns, one on each corner and one in the middle on each long side. I plan on installing a screen, maybe 3/8" or 1/2", around the inside of the six columns. So with that keeping the critters out, and the slate top keeping the weather out, I guess I should be good. I was unsure if perhaps something additional was needed as a spark arrestor.