Insert extending on to hearth?

[qwerty]

I've notice that some inserts are designed to extend beyond the opening of the fireplace itself and onto the hearth. Does this provide significantly better heat distribution into the room? It stands to reason that the more of an insert there is out in the room, the less chance there is for the heat to be lost to the chimney. Or is it that a blower remediates this issue well enough that efficiency is not a consideration.

The some of the flush-fitting inserts are quite attractive and seem to reduce the chance of a child or pet being burned. However, I kind of ruled them out on the basis of efficiency concerns. Was I being too hasty?

 

[carpniels]

HI qwerty,

Yes, you were too hasty. The blower provides the air to bring the heat from the stove (insert is a stove in a fireplace) to the room it is located in. Most are designed sticking out because most fireplaces are not deep enough.

Look around again. Lopi declaration and similar models are great and safer for kids.

carpniels

 

[TresK3]

Qwerty-

I had just the same question a few weeks back. Here's another consideration: clearance to combustibles. We wanted a Hearthstone Clydesdale, but because it sits out into the room a bit you have to have greater clearance to your lowest piece of combustible material (mantel or trim, etc). With an insert that sits flush to the fireplace you can usually have combustibles lower down the wall. We ended up with the Fireplace Xtrordinair FPX-33 Elite for this reason. It was installed about 1-1/2 weeks ago and looks great. Seems well made, but we've only built a very small fire 'cause temps are still in the upper 80's to 90 around here.

(Side note: Wow, some asked a question that I actually have some experience with! I must be learning something around here)

 

[MrGriz]

I do think that there is an increased amount of radiant heat gained from an insert that protrudes from the fireplace versus one that is flush. That being said, I don't think the increase is a night and day difference.

One of the reasons I chose the Osburn 2200i with the bay design is because it protrudes from the fireplace. The bay design provides an incredible view of the fire, especially when sitting at an angle to the unit. I am sure that it also radiates heat into the room better than a flush mount when the blower is not on, or is on at very low speed.

IMO, having a distribution blower in any insert is a must, they do a great job of getting the heat out into the room. I would make my decision based more heavily on the look that you like better, rather than any benefit gained from an insert that extends onto your hearth. TresK3 makes a great point also, the clearance to combustibles may also become an issue with an insert that sticks farther out of the fireplace.

 

[Dunadan]

My Lopi Revere extends out onto the hearth. I had been looking at the Avalon Ranier (same manufacturer) which didn't stick out, but chose the Revere for two main reasons -

1. I wanted a cook-top surface so in the event of a power outage I could always heat up something to eat.
2. The extra heating capability that comes with more exposed stove surface area.
3. I liked the look of the insert coming out onto the hearth.

I'm not saying a flush mount insert with a blower won't work, but I have a blower too, and I'll bet my Revere with blower will put out more heat than a flush mount stove with blower (all things being equal). How much more heat? I have no idea, but I know it has to be a bit more. Also, when I'm not looking for quite as much heat, I can turn my blower off.

On the other hand, there are a couple of downsides. My Revere pretty much comes out to the edge of my hearth so I put a couple large pieces of slate down over the wood floor to protect it. This year because my 9-month old is crawling, we're putting up a Hearth Gate for protection (my older kids - 9 & 11 know not to touch or play near the stove). The only difference having an insert that extends out onto hearth is that we need to allow a bit more room (I believe the insert extends 9" onto hearth) when positioning the gate.

Bottom line, I think there are pros to both, and depending on what's most important to you will determine what way to go.

 

[TresK3]

Looking at the pictures, I think it's the Avalon Perfect Fit that sits flush; the Ranier seems to stick out. Basically the Perfect Fit, the Lopi Declaration and the Xtrordinaire FPX-33 Elite are the same stove from the same manufacture with different front facing options. We liked the "Classic Black" from FPX, so went with that one.

 

[Dunadan]

The Avalon Ranier sticks out maybe an inch or two. It's not one of the new true "flush mount" units like the Declaration, but I would not consider it by any means a unit that really extends out onto the hearth.

 

[Rhone]

My $0.02, Inserts that sit out on the hearth slightly will fit in more fireplaces as already mentioned. In my opinion, they are slightly more efficient than those flush but trust me not that much more as mentioned the blowers are probably like 95% of what gets the heat out and distributed. With it slightly out means you can use what they call the "cooking" surface for food. Those "cooking" surfaces are usually insulated so they're more like warming surfaces. My insert has a 5" cooking surface as it sticks out slightly on the hearth and it's insulated so I'm lucky if it ever reaches much over 200-300F, I don't have a thermometer to say the exacts but did put a frozen thin-crust pizza on it and after an hour the cheese was slightly melted. I know the Osburns "cooking" surface has air blowing underneath it so it's unlikely to get too hot either. The Pacific Energy Summit inserts have their cooking surface insulated as well.

Now, as for those that sit out need more clearance to mantel, I believe it's the opposite. Those that sit flush need more clearance to mantel than those that stick out. Any flames that are coming out the insert, if it's installed flush the flames will have a chance of hitting your mantel directly, or the hottest air in direct contact. If your insert is sticking out 6" if flames are coming out the front your mantel above is likely to be behind the direct contact or hottest part of said flames. To back up my idea, Jotul Kennebec insert manual page 8 shows if your mantel sticks out only 3 1/2", you need 37 1/2" from floor to make clearance. If your mantel sticks out 12" you need more clearnace 43 1/2" from floor. It's a stepped picture. That would imply, if your insert sticks out 6" and your mantel sticks out 9 1/2" with an insert that sticks out 6" you only need 37 1/2" from floor. If your insert is flush the mantel needs to be 42" above. But, as mentioned although one that sticks out may reduce your clearances to combustibles above it increases how big your hearth has to be as you need 16" or 18" usually in front of the loading door and, having it out 6" will mean your hearth needs to be 6" longer than one installed flush.

 

[karl]

How do you define sticks out? I just put my Summit insert in the fireplace and it sticks out 6 or 8 inches. I always kinda thought of it as a flush mount, because i have seen other ones that appear to stick out more. How far to the longest ones stick out? Also are there any that don't stick out at all?

 

[Dunadan]

For the record, the Lopi Revere stove top is definitely not insulated.

 

[Gooserider]

My $0.02, Inserts that sit out on the hearth slightly will fit in more fireplaces as already mentioned. In my opinion, they are slightly more efficient than those flush but trust me not that much more as mentioned the blowers are probably like 95% of what gets the heat out and distributed. With it slightly out means you can use what they call the "cooking" surface for food. Those "cooking" surfaces are usually insulated so they're more like warming surfaces. My insert has a 5" cooking surface as it sticks out slightly on the hearth and it's insulated so I'm lucky if it ever reaches much over 200-300F, I don't have a thermometer to say the exacts but did put a frozen thin-crust pizza on it and after an hour the cheese was slightly melted. I know the Osburns "cooking" surface has air blowing underneath it so it's unlikely to get too hot either. The Pacific Energy Summit inserts have their cooking surface insulated as well.

Now, as for those that sit out need more clearance to mantel, I believe it's the opposite. Those that sit flush need more clearance to mantel than those that stick out. Any flames that are coming out the insert, if it's installed flush the flames will have a chance of hitting your mantel directly, or the hottest air in direct contact. If your insert is sticking out 6" if flames are coming out the front your mantel above is likely to be behind the direct contact or hottest part of said flames. To back up my idea, Jotul Kennebec insert manual page 8 shows if your mantel sticks out only 3 1/2", you need 37 1/2" from floor to make clearance. If your mantel sticks out 12" you need more clearnace 43 1/2" from floor. It's a stepped picture. That would imply, if your insert sticks out 6" and your mantel sticks out 9 1/2" with an insert that sticks out 6" you only need 37 1/2" from floor. If your insert is flush the mantel needs to be 42" above. But, as mentioned although one that sticks out may reduce your clearances to combustibles above it increases how big your hearth has to be as you need 16" or 18" usually in front of the loading door and, having it out 6" will mean your hearth needs to be 6" longer than one installed flush.

I have to disagree RM... The idea on the clearances is not to prevent flames from hitting the wood, but to prevent the wood from getting to hot due to radiant heat exposure when the stove is operating normally (door closed, etc) The reason for the increased clearance requirement on trim that sticks out further is that it is more exposed to radiant heating energy

I will admit that I haven't done comparisons of clearance requirements on inserts, but I know they vary from unit to unit, and I think the earlier posters may be right when they say the inserts that are flush with the fireplace front would have lower clearances than ones that stick out - If you have less surface area to radiate, you should get less heat exposure... It may also be a function of the unit's size - I suspect the flush fit units will tend to have smaller fireboxes. For instance I know the Hearthstone Clydesdale has huge clearances, but it is also a monster class firebox...

Gooserider

 

[TresK3]

Some stoves are truly almost flush to the wall. The surround kit for FPX 33-Elite (and it's twin siblings) comes off the wall about 1". Nothing extends beyond that (I'll try to post a picture of mine over the weekend).

As for clearance to combustibles, you have to read the manuals carefully (always a good idea) to see from where they are measuring. For the Ranier, they measure 31-1/2 inches from the top of the stove, which is 21-1/8" inches tall. That means your total clearance from the hearth is about 52-5/8" inches. For the Perfect Fit (aka FPX 33-elite), they measure directly from the hearth and the clearance reads 41"

Goose makes a good point about firebox size, but interestingly the Perfect Fit has a 2.9 cu-ft box, compared to 1.8 for the Ranier, yet the Perfect Fit has a lower clearance. I guess those few inches sticking out from the wall make a difference.