Is this Micore????.....Close-up picture of Micore 300??...

[Intheswamp]

Thank You MicoreGuy. I just got off the phone with the homasote company (makers of NCFR) and Kozy Heat (maker of Fireplace). Bottom line is my install is ok. There should not be a next time, but if there was I'd use micore. Bottom line is w/ a ZC fireplace I could even put this thing right on wood and be ok. The issue is right in front of fireplace. I won't be having any fires in front and if I did I imagine the wood trim or flooring would ignite long before the NCFS which that is under 1.25 inches of solid granite and has fire retardant properties.

I'm glad to hear that you've gotten an "all clear". I would imagine that the fireplace company gave the best comfort with it's negligible clearance requirements while Homasote probably didn't give much.

Best wishes,
Ed

 

[Arc_Dad]

You nailed it Ed.

 

[Riegel]

Thanks to the MicoreGuy! If you are looking for Micore he will take care of you. I couldn't find anyone in my area that carried it. One supplier in Reading, PA had it but you had to be a licensed contractor to purchase it. Very frustrating!

Now I can start my hearth extension project.

 

[Intheswamp]

Ok, anybody want to ID this micor for me. This is what I picked up today. Does it look like micor that you've worked with???

Thanks! Ed

 

[billbaehr]

Looks like you have an accoustical panel made of Micore 300... typically used for sound insulation / absorption in offices, sound rooms, theatres etc.. Same stuff, just with dimples.

 

[greythorn3]

can you tile micore like cement board? and whats its benefits over cement board for a hearth?

 

[billbaehr]

1/2" Micore 300 has a higher R-value (1.02) for radiant heat protection than four 1/2" thick pieces of cement board. It does compress under weight, so a 1/4" or 1/2" cement board overlay is highly recommended if you are going to tile over it. Its semi-rigid and cuts easily with a box cutter. Non-fortified thin set mortar is the preferred adhesive, but you can get away with mastic.

To answer your specific questions, Micore costs about the same as four pieces of cement board, if you can find it locally. If not, it might cost a bit more because of shipping. It provides for a lower profile (only a 3/4" rise compared to 2" with cement board), is much lighter than cement board and is easier to work with. Aside from those things, they both perform the same function and both can be installed like tiles, as long as the edges don't have gaps.

Hope this helps!

 

[G-rott]

Just a note on using mastic on your hearth, it's not non-combustible. I'd hate to see someone go through all the trouble to get micore then use mastic and fail at inspection time.

Garett

 

[billbaehr]

Garret is partially correct. Not all mastic is non-combustible. Same goes for thinset mortar and cement board.

Some types of thinset, mastic and cement board contain fortifiers and/or binders that are definitely combustible. Some mastic, such as roofing and some tile, use solvents that are combustible when wet, but not when cured. However, to say that ALL mastic is either combustible, or non-combustible for that matter, would be incorrect.

I think the point here is to ALWAYS check the manufacturer spec sheet to verify that the product you are using is non-combustible. When in doubt, ask... or move on to another product that is safe without question.

Please also note that "fire resistant" is not the same as non-combustible.

 

[Intheswamp]

can you tile micore like cement board? and whats its benefits over cement board for a hearth?

greythorn2, micore has very little structural strength. Use it only as an insulation layer. Once layered between your floor/plywood and some cement board it will help to "level" things out between the other layers. In some situations where a higher R-factor is required you may need to use more than one layer of micore. Most recommendations are for *not* using any adhesive between it and it's neighboring layers. Cement board screws are simply screwed through the cement board, micore, and into the base material (floor, plywood, whatever). The screws are normally considered small enough not to conduct enough heat to be a problem. An un-modified thin-set is used to attach the finish tile/stone to the cement board.

Cement board for structural (and a small amount of R-factor benefit) and micore for insulation.

Hope I wasn't too confusing.

The reason I was wanting to get a positive ID on the "micore" is that I bought this from a place over the phone. In conversation with them at their place of business and then again on the phone, the conversation was about "micore". They are closed on Saturday so they left it under their back shed for me. The trick is that I had to drive 125 miles one way for it. The invoice that they left for me was hand written and stated "microboard". I'll be calling them today to verify what I have here.

Thanks,
Ed

 

[billbaehr]

can you tile micore like cement board? and whats its benefits over cement board for a hearth?

Cement board screws are simply screwed through the cement board, micore, and into the base material (floor, plywood, whatever). The screws are normally considered small enough not to conduct enough heat to be a problem.

I've been told by both the local building inspectors as well as an insurance inspector that any metal screws that can radiate heat through the micore and into a combustible material will not pass inspection and will need to be removed. That leaves adhesives as the only viable option.

That said, I understand that the rules change from one inspector to the next, which is quite frustrating. The only important opinions, however, are the ones of your local inspector and your insurance company... so you should contact them prior to starting your project.

 

[Intheswamp]

can you tile micore like cement board? and whats its benefits over cement board for a hearth?

Cement board screws are simply screwed through the cement board, micore, and into the base material (floor, plywood, whatever). The screws are normally considered small enough not to conduct enough heat to be a problem.

I've been told by both the local building inspectors as well as an insurance inspector that any metal screws that can radiate heat through the micore and into a combustible material will not pass inspection and will need to be removed. That leaves adhesives as the only viable option.

That said, I understand that the rules change from one inspector to the next, which is quite frustrating. The only important opinions, however, are the ones of your local inspector and your insurance company... so you should contact them prior to starting your project.

The only important opinions are the ones that keep your family safe...I won't say that the government or insurance companies keep us safe but they are the organizations that we must yield to in these matters...just go a little be further and satisfy to yourself that what they mandate is good enough.

Ed

 

[billbaehr]

[/quote]
The only important opinions are the ones that keep your family safe...I won't say that the government or insurance companies keep us safe but they are the organizations that we must yield to in these matters...just go a little be further and satisfy to yourself that what they mandate is good enough.

Ed[/quote]

I'll give you a "true dat" on that one Ed. Each installation we perform carries the burden of knowing that the difference between a warm, safe home and a family's worst nightmare rests on our ability to gather and apply as much knowledge as possible. This is why I religiously check material information. Its why I learn building code and insurance and manufacturer requirements, and then exceed them. Its why I walk away from a job when a customer insists that I cut corners and compromise safety in order to achieve a certain "look" Its also why I joined this forum.

Would a properly lined wood stove radiate enough heat through a screw in your hearth to catch a sub floor on fire? The thought of it seems ridiculous... and odds are that it would not... but for as long as there is a one professional with some knowledge of the subject who tells me it actually could (there are more than a few), then I'm definitely going to avoid it. Perhaps I am being paranoid, but I very much enjoy sleeping soundly when my head hits the pillow.

 

[raybonz]

The only important opinions are the ones that keep your family safe...I won't say that the government or insurance companies keep us safe but they are the organizations that we must yield to in these matters...just go a little be further and satisfy to yourself that what they mandate is good enough.

Ed[/quote]

I'll give you a "true dat" on that one Ed. Each installation we perform carries the burden of knowing that the difference between a warm, safe home and a family's worst nightmare rests on our ability to gather and apply as much knowledge as possible. This is why I religiously check material information. Its why I learn building code and insurance and manufacturer requirements, and then exceed them. Its why I walk away from a job when a customer insists that I cut corners and compromise safety in order to achieve a certain "look" Its also why I joined this forum.

Would a properly lined wood stove radiate enough heat through a screw in your hearth to catch a sub floor on fire? The thought of it seems ridiculous... and odds are that it would not... but for as long as there is a one professional with some knowledge of the subject who tells me it actually could (there are more than a few), then I'm definitely going to avoid it. Perhaps I am being paranoid, but I very much enjoy sleeping soundly when my head hits the pillow.[/quote]

I like your way of thinking! The code is the least one can do and if you're willingand able to exceed the code then you're providing an extra margin of safety.. An ounce of prevention is indeed worth a pound of cure..

Ray

 

[Intheswamp]

I definitely agree on meeting safety requirements and then some. Not to mention myself and wife, but my grandbabies sleep under this roof, too. I would be hesitant on using screws under the stove and immediately in front of the stove. Using a glue to hold the micore to the subfloor/plywood should be ok because the R protection ends on that side of the sheet of micore. Using a glue between the micore and cement board is another thing, though. The glue has to attach to two very different surfaces. Using a mastic was suggested and then cautioned about...which mastics would be safe to use? I'm going to be building a hearth pad before long and really want to find this stuff out. My intentions earlier was to use the screws around the perimeter and let the center area of the pad lay with the weight of the stove on top.

Not trying to be argumentative here, but if the screws are not good for using on the hearth pad why are they allowed for attaching heat shields to combustible surfaces (such as walls and mantels) when you need to reduce clearances? The screws and copper/ceramic/whatever standoffs are still transmitting heat to the combustibles. ????

Like I said....I really want to know as I want to do this ONE TIME. I've got the micore in hand now and I'm waiting on this rainy spell to stop before trying to haul the plywood home (my fortune tells me if I try now that it'll rain 3 inches on the way home! :shut: ) I'm going to get some cardboard and start making some mock-ups of the pad...I like the idea of a pad with the corners cut off...seems more "toe friendly". I've got a few nooks and crannies to deal with, too, so a template will be good to have.

Ed