Open Fireplace Liner (Block-Off Plate)

[wburke820]

Hello,

I have an open fireplace which I want to leave open because I don't think the cost of an insert would pay off for where I live. I saw the article about a bottom block-off plate (https://www.hearth.com/econtent/index.php/articles/making_a_block_off_plate/) but it seems to be talking about an install with an insert because it is just 2 inches above the fireplace opening. I had the chimney inspected and it does have damage so I was planning on installing a stainless steel liner but I am not sure how to do a bottom block-off for an open fireplace. Can I use the same article as the one I am referring to above or should the block off plate be in a different location? Should it be at the top of the smoke chamber? Any help would be much appreciated because I have not found any articles talking about this topic.

Thanks,

Bill

 

[Shari]

Bill,

1st: Welcome to hearth.com! Lot's of good folk hang out here!

EDIT: Are you planning on burning in a fireplace or installing an insert/wood stove?


Shari

 

[branchburner]

I was planning on installing a stainless steel liner but I am not sure how to do a bottom block-off for an open fireplace. Can I use the same article as the one I am referring to above or should the block off plate be in a different location? Should it be at the top of the smoke chamber?

Hopefully a sweep and/or mason will chime in here. Top of the smoke chamber, where the old flue tile begins, makes sense. Definitely NOT like the one pictured in the article, the smoke will pour out into your room. You will likely want to keep using the existing damper, and the smoke will funnel from there into your new liner above.

BUT - the new liner needs to be correctly sized according to the dimensions of your fireplace opening - it is important to get this right and not put in a new flue that is too small. Search online - there are some charts/tables that offer guidelines to sizing. If you post the particulars of your fireplace perhaps someone here can give the answer.

PS - I am correct that this is simply a new liner for a fireplace, with NO stove or insert at all?

 

[Shari]

I edited my comment.

Shari

 

[wburke820]

Yes, you are correct, NO stove or insert.

The dimensions of the fireplace are 36 W x 30 H x 18 3/4 D, the W & H are the front dimensions. Based on the dimensions of the existing flue, the only liner I would be able to fit would be a 6" so hopefully that would work. If anyone thinks it would not, please let me know. Also, when is it required or recommended to insulate the liner?

Thanks.

 

[wburke820]

Shari,

Planning on burning in a fireplace, no insert or stove.

 

[BrotherBart]

A open fireplace that size requires something north of 70 square inches of area inside the flue. A six inch liner will be 28 square inches. Illegal and sure to fill your house with smoke and carbon monoxide within minutes of lighting a fire.
.

 

[Shari]

Ah, okay, now we are on the same page.

In a typical masonry fireplace, there is a damper (cast iron or steel) installed just above the smoke shelf inside the chimney. The smoke shelf is the area just above the firebox - where the firebox slopes forward. Your fireplace should have had a damper originally in this location.

You indicate your chimney is damaged - sorry, can't help you with what or how to reline a chimney for an open fireplace but regarding your damper: Have you looked into a chimney top damper, something like this: http://www.chimneydampersource.com/locktopdamper.htm

I don't know if relining with a SS 6' liner is possible due to inspection codes (someone else will have to address this issue) but I am thinking it just might be less expensive to install the chimney top damper and simply not use the fireplace other than for decoration.

Shari

 

[wburke820]

Shari,

I guess I am using a poor choice of words as I am new to having a fireplace, the chimney is not damaged, it's the original flue liner inside the chimney that is damaged. But according to BrotherBart, it sounds like the fireplace will have to be strictly decorative unless I invest in an insert that has a 6" flue output anyway. I was looking into the Jotul 450 but I can not justify the cost.

Thanks for all the help and input from everyone.

 

[branchburner]

Actually, I think it would be easier to justify the cost of re-lining the chimney if you DID get a stove or insert. Just having a fireplace gives no financial benefit - it will not pay you back for re-lining with any future savings. Having a stove/insert AND re-lining could pay back all costs within a few years, from money saved on heating.

You have a good company as a neighbor: (broken link removed to http://www.buckstove.com/wood.html)