the only concern I have at this point, is the guy at the stove store and the guy doing the tile BOTH tell me that putting a sheet of hardyback or duroc (spelling?) and then laying the tile over that will be sufficient for the 1.5 R requirement however.... I did some research and even went down to the local hardware store.... I have found that either board they use under tile only comes to at most .24 on the R scale.... and the tile way less than that I dont understand how they get the 1.5 from those numbers..... How can that be right??? all of you with the Englander 30 can anyone tell me that is how they built their pad??? Thanks again everyone for all your help.....
Amusing. Durock, Hardibacker, and Wonderboard are all types of cement or mortar board commonly used for tile backing on floors and walls; I prefer Durock myself. I was planning on using tile over Durock around my existing raised hearth to get the required extension needed for the Englander over the old Earth Stove here. However, as you point out, they are all rather low in R value. Sweeps has a list of R values for many common types of backer boards and brick and tile. 1/2 inch Micore 160 board has an R value of 1.27, the best of the 1/2 inch backer boards. Tile is only R 0.02, though, so you need more than Micore 160 and tile to get to R 1.5.
(broken link removed to http://chimneysweeponline.com/horvalue.htm)
Mike.... thanks for the phone call today.... Ended up getting the 30..... they are delivering it to the stove store here and they will bring it out when they come to install... turns out my neighbor's son in law does tile work.... so I called him and he is going to come over this weekend.... and get the job done.... the only concern I have at this point, is the guy at the stove store and the guy doing the tile BOTH tell me that putting a sheet of hardyback or duroc (spelling?) and then laying the tile over that will be sufficient for the 1.5 R requirement however.... I did some research and even went down to the local hardware store.... I have found that either board they use under tile only comes to at most .24 on the R scale.... and the tile way less than that I dont understand how they get the 1.5 from those numbers..... How can that be right??? all of you with the Englander 30 can anyone tell me that is how they built their pad??? Thanks again everyone for all your help.....
OK, take a deep breath. You are not getting correct info. A single sheet of hardibacker or durock are not going to make the required R value. This is pretty straight forward. Durock Next Gen has an R value of .78 per inch of material. If you want to use that product it will take 2" (4 - 1/2" sheets)of Durock NextGen under the tile layer to meet Englander's requirement for the 30NC. Hardibacker has less insulative value and the sheets are thinner. Figure about R =.5 for one inch of material, or 3" to meet the requirement. You can reduce this requirement by introducing a bottom layer of 1/2" Micore 300. That would have an R value of 1.03. Add a layer of 1/2" Durock Next Gen on top and the tile and you are close enough.
It is regionally available. I haven't tried to buy it so I will have to rely on others that have searched for it. This question comes up annually so I will refer you to past discussions.
https://www.hearth.com/talk/threads/where-can-i-buy-some-micore.72058/
Another material that can be used is Fibrefrax Duraboard:
http://www.fiberfrax.com/
Micore 230 is $37.50 a 20"x72" sheet with free shipping at this site:
(broken link removed to http://www.mantelcraft.com/fireplace-facing-systems/micore-board-cv230/)
It has a rated R value of 1.16 per 1/2 inch of thickness (k = 0.43). You could get 2 sheets and butt them up for the 40 inch width and cut them to the required 53 inches or 60 inches in depth (36 x 60 is not wide enough). Then put Durock Next Gen down over it with an R rating of 0.39, and tile it for 0.02 for a total of an R of 1.57. You will have a one inch plus tile height hearth. You can cover the rest of the non-heat proof raised tile area in 2 layers of Durock, or even with a 1/2 inch plywood or OSB and a layer of 1/2 inch Durock over that. Durock comes in 3x5 foot sheets for about $10 a sheet here. 1/2" OSB is ridiculous at $15.50 a sheet now. Still cheaper than Durock at .48 cents a sq ft vs. .67 for Durock. You screw Durock to the subfloor with special wide screws and tile right over it with thinset mortar. Durock is easy to cut and work with, and does not crumble or crack like Wonderboard.
StihlHead...... I had to laugh after reading your post.... I have smoked my brain so much in the last 24 hours trying to figure this thing out that my brain started to change the numbers in my head... thanks for slapping me and bringing me around... when I found that micore board..... somehow I changed the width requirements from 39 to 34".... I cant
believe that the people who would be held responsible if something went wrong, are telling me it is ok with the one sheet of durock and the tile and the person who does not know
anything is the one who is saying to hold on for a sec.... (me) of course, it would be MY family who burns up so I have extra incentive I guess....
DenverDan.... thanks for the response... and maybe you were not too late... I am going to spend the day trying to find it local anyway that I can... if that doesnt work then I will have
to hold up the project and order it online.... now the guy who is doing the tile wants to start friday (tomorrow) instead of sat...... so If I cant find it local..... things are just going to have to slow down until the shipment gets here... Now at least I know why he is in a rush.... He leaves Monday for disneyland with his family..... LOL..... will check in later and let
you guys know what I found....
hey russ,
talked to your tile guy today. seems like he has a good head on his shoulders i think he's got this thing figured out.
really nice dude BTW
Mike... thanks for everything.... I spoke to him shortly after he spoke to you... he said the same about you.... I think he understands more now... He didnt understand
the whole R value thing.... he thought I was being paranoid.... but he has a better understanding of it now... I just wish I could have gotten my hands on some 3/4" micore....
there would have been no issues and the wife could have one flat area tiled instead of raising it up..... that has been the biggest issue with this thing... keeping my family safe
at the same time trying hard to give her what SHE wants.... and what she DIDNT want was for any part of it to be higher than the other for anyone to trip on.... my youngest is
just about to turn three... so didnt want any accidents.... the other part is, the tile guy is hell bent on getting this done THIS weekend as I believe he is going on vacation but that didnt leave me any time to educate myself and get the right materials for achieving the 1.5 R value.... I wish I would have just dug into it a little more and realized the whole R value thing BEFORE I called him.... the stove people cant install until the 19th anyways.... so I thought I had time.... when we decided to go with doing the tile instead of the pre fab monster sized hearth... it was the only choice to call him as he is a good family friend.... with all the phone calls I have made in the last 48 hours, I have come to the realization that the stove people at least around here our ignorant when it comes to the Englander.... NONE of them even knew a thing about them.... INCLUDING the guy who Home Depot farms out the installations too! That one blew me away.... I asked him how in the world he could not know anything about the Englander when Home Depot sends all its customers to YOU for the install? All I got was silence... LOL...... but I think we have it all worked out and I am done.... Was I overreacting to the 1.5 R value thing??? EVERYBODY locally told me not to worry about it... but everything everyone here on the forum told me i HAVE to have the 1.5 anyways... Mike... Thank you as well as everyone for all the help and advice... I am so tired of all of this that I am just ready to pack up and move back to the desert... LOL.....
You do not want to tile directly to Micore... not made for that and no string enough material to hold up a heavy stove. Durock is made for tiling, and for being a substrate for flooring.
I found that making my ex happy was simply impossible. So you just have to go with structural and code requirements, and live with her dislikes. Short of redesigning the house there is not much that you can do to make a level hearth. As for the R value thing, if you have home insurance, or are ever inspected by the building dept. for the stove or anything else, or you have a fire and they investigate? All those things require that you have the correct heat insulation in the hearth for the stove. The building dept. here will refer to the Englander requirements.
Everyone says it is no big deal until is becomes one, and then they are all suddenly nowhere to be found. I found that out when I was flagged for my non-permit garage here. Oregon can be a PITA when it comes to code enforcement. Some counties in OR are a real bytch and others are more slack. Code enforcement in my county is a PITA, and there as a big flap over it in the paper here last week here. A guy had some new plumbing inspected on his 70 year old house, and the inspector noticed some non-code work done previously and flagged it. That led to more than a year of remodeling, huge costs and issues with permits and county code enforcement and updates. He has since released a published account of the whole thing and submitted it to the state.
Woo Hoo ! Another 30 Burner Welcome to the fold. I threw mine one top of the ol' basement slab, so can't say I had as many issues as you. But I can say that you'll love your stove just as much as I love mine.
As I type it's chompin' it's way thru a mixed load of dry oak/ash and wet oak. Get to know it and the wife'll be running around in her skivvies in no time...
thanks Stihl......... I just got off phone with tile guy... we will frame in where we are raising with wood.... double layer over the wood with Micore.... then 1/2 inch of durock on top of that so he can tile in......... does that sound right???
Yah, that will get you an total R value of 1.03 + 1.03 + 0.39 + 0.02 = 2.47, more than enough to deal with the heat.
I had the wrong K value for Micore 300 above, it is 0.49 and not 0.458 (corrected above). From the USG web site Micore 300 has a K value of 0.49, and Durock Next Gen has a K value of 1.92.
BTW, where do you live? I used to live with my ex just east of Elkton.
I have been everywhere in Oregon, most places many times over. I know Cave Junction well. I have been there many times, selling sheep in Crescent City and off-roading all over up there, camping at Onion Mtn. as well as kayaking the Rogue and the Illinois, and wine tasting. One of my favorite wineries is Foris Vineyards down there. I even did the cave tour 30 some odd years ago when I went through there on my Motorcycle (wild days of my youth, I had a Suzuki GS 750). I have a few stories to tell about CJ. Bigfoot was sited there many times
As for living out of the city, I know what that is about. I bough an acre out here in the boonies... west slopes of the Cascades, about an hour east of PDX. I live a very low profile life here. I used to be an engineer making 6 figures in the SF Bay Area for some very large computer companies. That nearly killed me. My job was off-shored to China and I sold my house in San Jose and moved in with my then future-ex and I got hooked on living out in the sticks. We split up and I bought this place.
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