wrote:
"TomR" wrote:

What was interesting is that they recommended tearing this one down
to the roof line and then replacing it with two "triple wall
stainless steel 'b-vent' chimneys" -- in other words shiny new metal
chimneys. They said it is much easier to install and they can do the
whole thing in one day.

That is what someone on this thread suggested previously. I also
suggested that approach with a
framed/sided chase around it.

I remember that and I did keep that suggestion in mind -- thanks.

The latter would certainly
look better and I'd wonder if they can go high enough
to meet code without a chase.

I agree, but I also learned more information yesterday regarding the
required height off the roof for a Type B vent. I'll explain more about
that below.

You are going to
make sure they get any necessary permits right?

Yes. If there is ever a fire, especially a chimney fire, I would want to
have on record that I had a permit for the chimney and the installation
passed the final inspection on the permit. Plus, it is a rental for me and
the cost of all of this is a deductible business expense, and the cost of
the permit is negligible. Also, in the town when the property is located
the construction officials are very fair and reasonable and easy to work
with.

But it looks right now like rebuilding the chimney from
the roof up is the least expensive. That;s because
they are only rebuilding part of it, where with the other
approach they have to run the new vent pipe all
the way to the boiler.

Now that I know more about what my options are, there may be a way that I
can cut down on the cost of the installation and still end up with a new
metal "chimney" (actually, I found out that it is called a "vent", which is
what you called it) all the way from the boiler up.

I'd also make sure that someone actually does an
inspection on the full chimney, running a camera
down there before doing any work. You don't want
to put a new top half on a chimney where the bottom
half is shot too. For example, the mortar could be
shot between the flue sections in the bottom half.
You could solve that by putting a steel liner in the
rebuilt chimney, but that obviously adds to the cost
and should be factored in if needed.

I agree, and that is one reason why I like the idea of two all new metal
vents from the bottom up. That way, there would be no issues with the
condition of the existing clay flues. Both of the companies that gave
estimates for rebuilding a new brick or cement block chimney said that "if"
they found that there was a problem with the existing flues, that would be
an additional cost to add new metal liners. Neither one actually looked
inside the existing flues when they did the estimate -- which I thought was
a poor approach on their part. So, by going with a new metal B-vent now,
from the boiler up, I won't have to worry about "if" the brick or cement
block chimney guys will say we need new liners.

Anyway, here's what I learned yesterday by doing more research on my own
after receiving the estimate for a B-vent chimney:

I found out that there is a difference between a "chimney" and a "vent".
The first link below describes that, although it is dated 1991.

I also found out that the height requirements vary with chimneys and vents
depending on the type of construction and the type of boiler, furnace, etc.
that is being vented into the chimney/vent. The second and third links
below describe that.

Basically, for any masonry chimney, or a Type L vent, that is being used on
an oil-fired, coal, etc. type of boiler, the height requirements are that it
must go up at least two feet higher than any point where the roof is within
10 feet horizontally from the chimney/vent.

BUT, for a Type B vent, which is only for gas-fired boilers etc. (which is
what we have), the height only needs to go up about 2, 3, or 4 feet above
the actual roof line where it comes through the roof -- depending on the
slope of the roof. After reading that, while driving around, I see lots of
metal B-vent "chimneys" that only come up two or 3 feet off of a sloping
roof, even when they are on the low side of the roof. I found that to be
VERY interesting!

Here are the 3 links:


http://www.homeinspector.org/resourc...-and-Vents.pdf



http://www2.iccsafe.org/states/newje..._Chapter24.pdf



http://www2.iccsafe.org/states/newje..._Chapter18.pdf



One thing I figured out after seeing a guy who was maybe 5' 8" or 5' 9" tall
from the last chimney company actually walk up on the roof and stand on the
roof itself next to the chimney and reach up to almost the top, is that it
would be easy for us to take down the existing chimney. At most, maybe a
roof jack ledge on the high side of the roof to stand on and reach right up
to the top and take down the chimney piece by piece, brick, by brick. They
are so loose they will come off by hand or maybe with a very light tap or
pry bar. Or, I have a large Werner "A-frame"(?)-type ladder that we could
place on the porch roof next to the chimney and reach the top of the chimney
from there without even getting up on the top roof where the chimney is
located. So, the cost of the demo will be almost nothing. Then, all that
will be left is to drop a metal B-vent down in each flue, connect it up at
the bottom, do the right cap routine at the top, and it's done -- no
scaffolding, etc. will be needed.

TomR wrote:
I own a property that has a badly damaged chimney. . . . ,

Just an update in case anyone who was following this is interested:

I later found out that, with natural gas appliances (my steam heat boiler
and hot water heater), it is permissible to use a smaller liner than 7
inches inside the original chimney chase -- even if the connector pipe going
into the chimney now is 7 inches -- as long as the input BTU's of the
appliances going into the chimney, and the height of the chimney/vent etc.,
are calculated correctly using a standard chart regarding the code
requirements.

Here's one link with those requirements:

http://inspectapedia.com/chimneys/Chimney_Flue_Size.htm .

In my case, the total BTU's going into the chimney/vent are 224 thousand.
And, given all of the other height specifications etc., I can use a 6 inch
liner in the existing chimney -- which will easily fit inside the 8"x8" clay
flue that has an inside dimension of 6-5/8 inches across.

That means that I can have a 6 inch aluminum liner installed inside the
existing flue and a 6 inch double wall "Type B" (B-vent) coming out of the
top of the existing chimney (after the existing chimney is torn down to just
above the roof line).

On Apr 28, 11:29*am, "TomR" wrote:
TomR wrote:
I own a property that has a badly damaged chimney. . . . ,

Just an update in case anyone who was following this is interested:

I later found out that, with natural gas appliances (my steam heat boiler
and hot water heater), it is permissible to use a smaller liner than 7
inches inside the original chimney chase -- even if the connector pipe going
into the chimney now is 7 inches -- as long as the input BTU's of the
appliances going into the chimney, and the height of the chimney/vent etc..,
are calculated correctly using a standard chart regarding the code
requirements.

Here's one link with those requirements:

http://inspectapedia.com/chimneys/Chimney_Flue_Size.htm.

In my case, the total BTU's going into the chimney/vent are 224 thousand.
And, given all of the other height specifications etc., I can use a 6 inch
liner in the existing chimney -- which will easily fit inside the 8"x8" clay
flue that has an inside dimension of 6-5/8 inches across.

That means that I can have a 6 inch aluminum liner installed inside the
existing flue and a 6 inch double wall "Type B" (B-vent) coming out of the
top of the existing chimney (after the existing chimney is torn down to just
above the roof line).

Good to hear you found a solution....