Hearthstone Heritage Installation- steel studs, ceramic, OAK

Now that I have this thing in and burning I want to post up my experiences so that all may benefit. Thanks to everyone who helped with my sometimes silly questions and concerns. Excuse the darkness of some images, I didn't have the time to lighten themup but certainly am willing to if it would halp anyone. Actually, please let me know if I can offer any clarification on this install. It was permitted and inspected.

This last Xmas I moved into a house built in 1963 with a masonry fireplace containing a Lopi Freedom Bay insert. Nice sandstone hearth with a short chimney that I had lined with a Homesaver liner right away as a safety item which was a waste of money since I tore it down the following Spring. The masonry was cracked in the rear among other things. The Lopi was certified but about 15 years old and was sold to a new home. Photoa1

The removed fireplace left a big hole in the floor, the wall, and the ceiling. I framed and the floor in with substantial extra support and several layers of plywood to make up the 2 inch floor thickness. Tongue and groove subfloor. Two extra 4x6 beams under there too. Once I was at grade in the house I built the wall and sheetrocked the holes. I then tried to find micore. Nope not going to happen. So I went with the steel studs and built a platform for the stove. I placed the studwork very close together for strength since this platform would support about 300 lbs of durock, a 500 lb stove, tile, mud, firewood, and the guys installing the stove. The studs feel flimsy but as in teh end the platform worked fine. I used slf tapping scers to attach the studs together and cut them with my steel cutting 14" chopsaw. You've got to size the platform right if you plan to use tile and you don't want to cut it. Biggest mental challenge was that. When putting tile on the top front and sides of the platform everything has to be just right. Even consider how far the tile will squish down into the thinset. Steel studs for platform, photo 1. Last dark photo.

The outside air is REQUIRED to be hooked up by my building inspector. The Hearthstone manual calls out a 3" duct which may be flexible almuminum. The old chimney foundation prevented me from dropping the duct vertically into the crawlspace so I utilized the space within the platform to route my duct. This one platform void is less protected than the others so I lined it with sheet steel. Don't crush the duct it cant' be replaced. Seal the penetration with fireblock.Photo2

2 layers of durock on top of the studs and one on the side. Each layer is seam sealed with the proper mesh tape and mudded with thinset. Also the layers of durock are glued together with a full layer of thinset. I measured and transfered the stud locations to the durock surface to be sure that all of the screws hit the platform studs. The second durock layer was screwed with no attention paid to the studs or the first set of screws. I cut durock with a circular saw easily. Don't crush the duct! Photo3

Now I set tile. This was new for me and I used ceramic floor tiles from Lowes. I liked slate but it is harder and the slate can be tracked. HD had a dark tile that was good but the inner clay was terra cotta and any chip would reveal orange. So Lowes had a slightly lighter tile with a dark core. Here they are all cut and set in place but not grouted yet. Caulk against the wall. The front corners required a three way stroke of luck. I used a minimum 1/4" gap but then eyeballed a little extra because I needed to. It worked fine. Photo 4

Grouted with sanded grout as dark as I could find without choosing the black grout. Then sealed just the joints with a little roller tool. Photo 5

Here is where the pros come in. I hired out the venting. The guys I chose had to be called back since the class A in the attic was less than 2" from wood and the chimney not plumb. They fixed those things but I understand that it is hard to get it perfect. photo 6

Here it is in place. There is a single telescoping piece of double wall between the stove and the ceiling which is just about 5 feet. Then there is 8 feet of class A Simpson straight out the roof extending 4 feet above the roof and about 3 above the ridge. Nothing attaches the double wall to the stove's collar. Nothing but the twistlok attaches it to the ceiling support. 3 screws hold it in the telescoped position. The installers were certain that this was proper and so was the inspector. I did have the two 4 foot pieces of Class A screwed together in the attic in addition to twistloking them. Photo7

Another view set back and showing the room better. I added the ceiling fan earlier this year. Photo 8

One of several break in fires.Photo9

So my first impressions. The horizontal nipple of the outside air kit is very nice since it allows some flexibility in plumbing. Slides right inside the 3" duct and ALL combustion air enters this nipple so those folks wanting to add a valve could do it here. The inspector would have failed me had this not been hooked up.

The stove drafts fine even on a 70 degree day which I chose for a break in fire. I ran the stove up to 150 with no odors or really anything but that was per the manual. Supposedly I could then go full temp but I chose to have another fire to 300 which did kick off the fumes but not so much burning paint as much as a hot cast iron pan smell. Reminded me of pancakes. Must be the vermont thing.

The final break in fire was last week when the house was 60 inside and the outside temp was about 55. I wanted to run her up to 450 or even 500 as the final break in but found myself cooked out of the room before hitting 350. We got to 400 just barely and finally got some good secondary combustion. Windows open to cool, not to vent stink. the first time past 300 is the end of the stink on this one.

The only funny thing I noticed besides the water either condensing on the inside of the soapstone from the smoke or oozing out of the soapstone was that the cement placed between the stones blistered out with a hollow blister. Once cool the blisters were like eggshells and were knocked off with my fingers to reveal a clean joint beneath. Is this normal?

I have some very dry wood I was using for the break in and since the stove takes so long to warm up it also means that the period of smokey chimney time is longer. It cleared up once I got past 300 stove top temps.

We all like it so far. We really like to look at it which is pretty important. The stove firebox is taller inside which means we see more flame before it hits the top baffle. This is good. The side door is fantastic for adding wood in this relatively shallow firebox.

Thanks again to all that helped me choose and plan this installation. Once I get the tile entry installed (matching the hearth of course) the orange carpet will be replaced with a grey. We like the stone, wood, and iron look. I have about 4000$ into this project not counting the demolition of the old structure.

Oh and on clearances. You will notice the pad is 4' deep by 6 feet wide. I have more than 18" on each side and the front with just about 11 inches to the rear where only 7" is required but the trusses required me to move it forward. The extra 4" will allow me to maybe put up a cool veneer someday.