Installing Micore

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
R

robertjp

Member
Oct 7, 2008
75
Western NY
OK so I finally was able to locate a piece of Micore. I had to stand on my head to get it. What a joke. Now that I have it, I need to figure out the proper installation. If anyone has used the stuff, here are a few questions I have:

1- Can I cut it with a regular saw since it looks like drywall?

2-How do I attach my Hardibacker cement board over the top of it? Screws?

3- I'm planning on laying the Micore (R1.03) over the wood floor, laying Hardibacker (R.2) on top of that, and then ceramic tiles. I need R1.2 for my installation. How would I add trim to it to cover the layers that are visible? What kind of material could I use for trim?

Does this installation seem ok? Thanks much in advance. Bob
 
robertjp said:
OK so I finally was able to locate a piece of Micore. I had to stand on my head to get it. What a joke. Now that I have it, I need to figure out the proper installation. If anyone has used the stuff, here are a few questions I have:

1- Can I cut it with a regular saw since it looks like drywall?

I always used a sheetrock knife & drywall square

2-How do I attach my Hardibacker cement board over the top of it? Screws?

Screws won't work unless you go thru to the subfloor.
As long as you're not ever planning on moving your hearth
pad without destroying it, that's the best way.
I've also used construction adhesive, but Micore doesn't give a good bond.
You can just lay your hardi-backer or whatever product you're using,
on the Micore & let the weight of your tile/thinset/grout hold everything down...

3- I'm planning on laying the Micore (R1.03) over the wood floor, laying Hardibacker (R.2) on top of that, and then ceramic tiles. I need R1.2 for my installation. How would I add trim to it to cover the layers that are visible? What kind of material could I use for trim?

Make your hearth pad big enough that you can use wood trim.
As long as your pad meets the requirements as prescribed by the stove
manufacturer, the wood trim will be outside the critical heat areas...

Does this installation seem ok? Thanks much in advance. Bob
Click to expand...
 
Just cut some today with a cheapy plastic box cutter.
 
A little thinset with a small v-notch trowel will bond your hardi to the micore. If you have a rasp or coarse file I'd cut the hardi with a knife (score well and snap), then clean up the edge with the rasp.

Using a knife makes a lot less dust.

You can use strips of hardibacker around the edge if you want to use tile for trim. If using wood I like to set the top edge of the wood just (1/32") shy of the top of the hearth and leave a grout line around the edge.

Don't Mastic for your tile on a hearth, it is not non combustible and has some give to it that can cause cracking if a point loaded (stove legs).

Post some pictures when your done.
 
Depending on your stove requirements.... edited see following posts
 
You can't be serious about Hardi backer are you? No R value? Not cement board? Does anyone else know if this is the case? What a nightmare this whole thing has been. Ask 5 people get 5 different answers from the R value, locating micore, now this, etc..............Jeez.
 
Sorry I was wrong, totally wrong. Hardi is non-combustible so you should be fine but R value is very low.... 0.13, and yes it is a cement board. I was confusing it with something else.

http://www.jameshardie.com/homeowner/products_backerboard_halfInch.shtml?openTab=jsnavLink0

https://www.hearth.com/econtent/index.php/forums/viewthread/9045/

I didn't use hardibacker because I wanted a full sheet. I could not find 4x8 sheets of it. Plus I needed more thickness and R value (Durock 0.39 per 1/2") . Durock worked out better for me.

Durock NextGen... http://www.usg.com/rc/data-submittal-sheets/panels/durock/durock-cement-board-submittal-CB399.pdf
 
This comes up several times a year. There are a whole lot of threads on the topic. Hardibacker is usable, but not ideal because it has cellulose filler mixed in. This got more complicated last season because the supplies of the original Durock and Wonderboard cement board had run out. All one can get now in those lines are the lighter, NextGen products. Fortunately Durock NextGen uses perlite as the filler which is mineral based and non-combustible. This was covered exhaustively last year because the specs were unclear and product messaging was conflicting. Canadian literature said it was ok to use for hearths, US offices said no. Regardless, we have no choice at this juncture. These are the products on the market. Hopefully USG and others will update testing specs so that we can lay it to rest. Regardless, I'm sure it will be a hot topic again this season.

Robert, the last time you posted about this hearth I thought you were going to use wonderboard. That is why no comments before this. If you have already laid the tiles, it may be ok. We haven't had any disaster reports with hardibacker that I recall.

https://www.hearth.com/econtent/index.php/forums/viewthread/75581/P22/#944791
 
I have not laid tiles yet but already purchased Hardibacker and Micore. I may have used the term wonderboard in a generic sense. I didnt know that it made much difference in brands, Thanks for the info. Hardibacker states one of its benefits is for non combustible construction. Whats the issue then?
 
Rob, no worries. I'm using Hardibacker 500 under the cement pavers in my install. I called Hardi and talked with a rep there, it's totally safe and non combustible. I won't be loosing sleep over it, that's for sure.

**edit**
I might take a small square that I have left over and hit it with the torch for a few minutes, see if it lights up at all. That'll certainly be much hotter than under the stove under the cement pavers.
 
robertjp said:
Cool, if you light it. let me know what happens. How thick are your cement pavers?
Click to expand...

I guess I won't bother, I just read on another thread that Elk tried to light a piece with his acetylene torch and it wouldn't even smoke. I just have a propane torch, no way would it light. The pavers are 1.75" thick.
 
G-rott said:
A little thinset with a small v-notch trowel will bond your hardi to the micore. If you have a rasp or coarse file I'd cut the hardi with a knife (score well and snap), then clean up the edge with the rasp.

Using a knife makes a lot less dust.

You can use strips of hardibacker around the edge if you want to use tile for trim. If using wood I like to set the top edge of the wood just (1/32") shy of the top of the hearth and leave a grout line around the edge.

Don't Mastic for your tile on a hearth, it is not non combustible and has some give to it that can cause cracking if a point loaded (stove legs).

Post some pictures when your done.
Click to expand...

When you say dont mastic your tile, you are not referring to grout are you?
 
robertjp said:
G-rott said:
A little thinset with a small v-notch trowel will bond your hardi to the micore. If you have a rasp or coarse file I'd cut the hardi with a knife (score well and snap), then clean up the edge with the rasp.

Using a knife makes a lot less dust.

You can use strips of hardibacker around the edge if you want to use tile for trim. If using wood I like to set the top edge of the wood just (1/32") shy of the top of the hearth and leave a grout line around the edge.

Don't Mastic for your tile on a hearth, it is not non combustible and has some give to it that can cause cracking if a point loaded (stove legs).

Post some pictures when your done.
Click to expand...

When you say dont mastic your tile, you are not referring to grout are you?
Click to expand...

I'm sure he's referring to mastic adhesive that uses a solvent base which evaporates as two surfaces stick. Mastic is combustible. Use thinset mortar.
 
Status
Not open for further replies.

Similar threads

K
Hearthpad
Replies
1
Views
511
The Hearth Room - Wood Stoves and Fireplaces
begreen
begreen
T
Hearth pad
Replies
6
Views
4K
The Hearth Room - Wood Stoves and Fireplaces
begreen
begreen
M
HELP! I'm trying to figure out the safe way to install my Stove
Replies
7
Views
742
The Hearth Room - Wood Stoves and Fireplaces
begreen
begreen
andrew777
Layering of Durarock and Micore300
Replies
4
Views
1K
The Hearth Room - Wood Stoves and Fireplaces
begreen
begreen
R
Woodstove pipe wall insulation
Replies
3
Views
1K
The Hearth Room - Wood Stoves and Fireplaces
bholler
B
Top Bottom
Back