Couple Questions before installing my Napoleon 1402 insert!

[WaffleIron]

Hey guys,
First post here! I've been lurking for a while and want to thank everyone who has contributied to this forum. After much reading I've decided I will most likely get a new fireplace insert and perform the install myself. However I have a couple questions still.

This is the Napoleon 1402 insert and it sticks out of the fireplace about 9 - 10 inches. Which means I'm going to have to extend/redo my hearth. So Question #1: Can I just buy one of these hearth pads from Northlineexpress and place that on my floor? It's 1 1/4" thick. (Also I've heard that directly below the insert is actually one of the cooler spots of the insert. I've always thought it would be the hottest. Is that true?)

Here is a link to the hearth pad:

northlineexpress.com/champagne-cork-48-x-48-double-cut-hearth-pad-ccdc-4848-19607.html

The manual for the insert states:
HEARTH EXTENSION / FLOOR PROTECTION:
Must be non-combustible and extend in front of
the insert and 8” on both sides with a minimum
thickness of .500” and a thermal conductivity fac-
tor (K) 0.84.


Question #2 is regarding the firebrick inside my fireplace. This insert is basically square but inside my fireplace the side walls are at an angle. And I don't think this insert will fit inside my fireplace with the current firebox/firebrick the way it is. Can I remove some of those firebricks on the side and back?
The manual says don't remove bricks from your chimney. But it isn't clear if it's referring to the actual bricks that make up the structure of the chimney or if that includes these firebricks.

Here is a link to another fireplace on this forum that has a similiar firebox as mine:
hearth.com/talk/threads/build-log-napoleon-1402-liner-install-sheet-metal-damper-crown-repair.147231/


And on a side note, my firebricks are cracked and there is very little mortor still there. If I continue to use this as a fireplace as it is now can I use high heat mortor caulking and and just seal those fire bricks up and be good to go?

Thank you!!

 

[weatherguy]

I had to remove some bricks to fit mine in.
If you only need hearth protection that pad will work.

 

[begreen]

Is the hearth raised above the floor by 6-8" or is it flush with the floor? If raised you may be able to just provide ember protection for the extension.

It's not unusual to have to grind out some upper firebrick in the corners to get the stove to fit.

 

[WaffleIron]

weatherguy: Thanks, I appreciate the input.

Begreen: The hearth is flush with the floor. Otherwise I would do exactly like you're saying. I'm still tempted to just install the insert and see how hot it gets in front of it. But I won't be up to code if I try that. I can't find a hearth pad that is quite the right dimensions for this.

 

[bholler]

But I won't be up to code if I try that.

And you might burn your house down to? Floor protection is not a place to skimp at all

 

[begreen]

weatherguy: Thanks, I appreciate the input.

Begreen: The hearth is flush with the floor. Otherwise I would do exactly like you're saying. I'm still tempted to just install the insert and see how hot it gets in front of it. But I won't be up to code if I try that. I can't find a hearth pad that is quite the right dimensions for this.

With a flush hearth you'll need full coverage out to at least 16" in front of the door. The hearthpad you gave the link to is for a freestanding stove and much too large. All you need is an extension with a rating of R=1.19 or greater. This is probably one the cheapest solutions out there.
http://www.woodlanddirect.com/Wood-...ns/HY-C-Black-Type-2-Hearth-Extension-18-x-48
Another option might be to cut open the floor and shave down the joist a bit so that a build up of plywood, micore and cementboard with tile gets you back to flush.

 

[WaffleIron]

Thank you! That's a better option already. I'll probably try that for a temporary solution.
But in the future I'd like to do just like you said. So when rebuilding the hearth, there is no air gap between any of those compenents correct? It's just laydown a sheet of plywood, followed by micore, then cementboard with tiles and grout? That doesn't sound too bad.

 

[begreen]

You'll want a layer of thinset on the cement board before you lay down the tiles.

 

[WaffleIron]

Yes! haha I'll do that.

Mind if I ask a couple other questions?.. After you install a stove/insert with a liner up your chimney you never clean your actual chimney again do you? (However you clean the inside of your liner regularly.)

And lastly would you have any advice for how to check the inside chimney condition by myself? I don't have enough room in my chimney to install an insulated liner. There is only clearance for the liner by itself. I'm told if the chimney condition is OK this is fine. But it sure is tough to see very far inside the chimney..

 

[bholler]

And lastly would you have any advice for how to check the inside chimney condition by myself? I don't have enough room in my chimney to install an insulated liner. There is only clearance for the liner by itself. I'm told if the chimney condition is OK this is fine. But it sure is tough to see very far inside the chimney..

The condition of the inside of your chimney has absolutely no bearing on the need for insulation. What determines that need is whether or not you have the required clearances to combustibles from the outside of the chimney structure. If it is an internal chimney you need 2" between the outside of the masonry structure of the chimney and any combustibles. For an exterior chimney only 1" is required. Many liner manufacturers require insulation to maintain the ul listing as well. This means you will either have to use an ovalized liner or remove the clay tiles to make room for an insulated liner

 

[WaffleIron]

bholler: Thanks. I was told with an exterior chimney as long as you have that 1" you don't need to use insulation on the liner. But if your chimney clay tiles are cracked you do need it. Since this house is already built how do I know if there is anything combustible too close to the chimney? I have to cut sheetrock near the chimney and look?

My chimney flue is 7 x 11. Inner diamater is more like 6.5 x 10. From what I've read including an individual who installed this exact stove if I remember right. You have to go with a 5.5 liner (instead of 6 like the stove originally calls for) and even then there is no room in the chimney for liner insulation. (But I guess I could use pour-in insulation like perlite? I've read of others doing it that way.)

 

[bholler]

But if your chimney clay tiles are cracked you do need it.

That has no bearing at all. it all has to do with clearances. For straight code if you have that clearance it does not even matter if there is clay there as far as insulation goes. But honestly for an exterior chimney you want insulation regardless for performance reasons.

Since this house is already built how do I know if there is anything combustible too close to the chimney? I have to cut sheetrock near the chimney and look?

You many times cant know which is why we insulate every single liner we install.

(But I guess I could use pour-in insulation like perlite? I've read of others doing it that way.)

Nope you actually need more room for pour in it requires 1" thick insulation all around it. What you will need to do is either an ovalized liner or remove the old clay tiles. There are also some preinsulated ovals available.

 

[WaffleIron]

Thanks for the replies, I appreciate it.