Floor Vents

[CT Burner93]

Hello!

So this is my second winter heating with wood in my raised/split-level ranch using my Regency I3100. I absolutely love it but I do have a rather hard time with heat circulation. The insert is located in the fireplace in the lower level family room of my 1750 sqft raised ranch. The stove can keep the lower level at 80-82 fairly easily but I am having a very hard time getting the air up the open staircase to the 2nd level. The heat must move down a narrow hallway towards the garage and then turn and go up the main staircase with main doorway/entry landing. I have tried multiple fans on the floor on the top of the stairs the landing and even the bottom hallway to try and circulate the heat but the best I can ever get is around 70 at the thermostat in the hallway right on top of the stairs.

I have read every single possible post I could on here for putting in floor registers. I feel this is my best bet for getting a more even temperature in the upstairs living room/kitchen/dining room. According to all the post i've seen it seems recommended to install a fire damper within the register. Despite all the posts i've read I haven't actually "seen" a picture of how this would look or even how it is done. Does anyone have any pictures showing an actual installation of a fire damper for a register between floors? Does the damper float inside the metal duct sleeve or is it attached in the middle or how does this work? I am not an HVAC professional and will most likely try to hire someone if need be but would like to be able to explain to them what i'd need and make sure it's done correctly. Would I need a metal "duct/sleeve" to fit in the hole and then attach the damper in the middle? I was looking at the one's at either

Atlanta Supply Co:

AtlantaSupply

Atlanta Supply is now JEDCO Supply

www.atlantasupply.com

or

Grainger:

https://www.grainger.com/product/DAYTON-Fire-Damper-2TGF5

Would either of these work for a register through the floor/ceiling? Any help or examples from someone who has previously done something like this would be greatly appreciated!

I have attached a layout of my floorplan and possible locations for the registers as well.

 

[kennyp2339]

I personally wouldn't bother with fusible registers, there to small for actual cold air return properties, plus in all honesty, the smoke will get you before the flames if a fire were to occur (you have an open stairwell), your not guaranteed that the damper will work either, it all depends on were the fire originates from in relation to the fused grate, now I would never suggest cutting in registers into a bedroom floor, thats unsafe (in fact the bedroom doors should be shut at night when someone is sleeping in that room, but cutting in registers between floors in common spaces like the living room, kitchen, dinning room, what ever common room is over the stove room would work.
Now onto the theory of floor registers, the simple 6x10 registers you see at home depot of forced air systems are not going to cut it, what you need is to establish natural convective loops. One of the best ways to do this is to make a cold air return cutting out a section floor - joist wide x 16" minimum long, located near an outside wall, then frame in a cold air boot at the bottom that protrudes into the ceiling of the room below by 18" this allows the cold air to drain down without mixing with the warmer air at the ceiling level, the air that draining down will be replaced by warmer less dense air there for the area your trying to warm up will get warmer, in your case the open stair well will facilitate a path for the warmer basement air to travel.

 

[CT Burner93]

I personally wouldn't bother with fusible registers, there to small for actual cold air return properties, plus in all honesty, the smoke will get you before the flames if a fire were to occur (you have an open stairwell), your not guaranteed that the damper will work either, it all depends on were the fire originates from in relation to the fused grate, now I would never suggest cutting in registers into a bedroom floor, thats unsafe (in fact the bedroom doors should be shut at night when someone is sleeping in that room, but cutting in registers between floors in common spaces like the living room, kitchen, dinning room, what ever common room is over the stove room would work.
Now onto the theory of floor registers, the simple 6x10 registers you see at home depot of forced air systems are not going to cut it, what you need is to establish natural convective loops. One of the best ways to do this is to make a cold air return cutting out a section floor - joist wide x 16" minimum long, located near an outside wall, then frame in a cold air boot at the bottom that protrudes into the ceiling of the room below by 18" this allows the cold air to drain down without mixing with the warmer air at the ceiling level, the air that draining down will be replaced by warmer less dense air there for the area your trying to warm up will get warmer, in your case the open stair well will facilitate a path for the warmer basement air to travel.

That was kind of my line of thinking but saw dampers were supposedly "safer"...I have a wide open stairway in middle of house and also have plenty of holes cut in soffits with access panels on them and even a wide open area above dryer where the exhaust is routed between the floors and out the side of the house. The vent would just be another connection to the common areas above (i'd line it with metal ducting) with the bedrooms on the complete opposite side of the house above the garage. If fire was going to spread through the floors it would have multiple opportunities to do so given the current home layout. Of course logic isn't always taken into account with codes or inspectors. I don't think I would want something obtrusive sticking down a foot or so from the ceiling though. I'd rather a flush ceiling vent, similar to like an AC return vent in white to match the ceiling. If I made it flush couldn't the staircase just be the cold air return (it has the front door there and is on exterior wall of the home so plenty of colder air there) and use a vent or two to send warmer air up into the above living room/dining room?

 

[peakbagger]

Talk to any fire pro and they will advise you against skipping them. If you have normal joist spacing they just go in between the joists with a floor grille above it. Yes it requires some basic tin knocking skills or someone to do it for you.

 

[CT Burner93]

Talk to any fire pro and they will advise you against skipping them. If you have normal joist spacing they just go in between the joists with a floor grille above it. Yes it requires some basic tin knocking skills or someone to do it for you.

Do you happen to have a picture of how it is done with the dampers? I just could not find anything anywhere no matter how hard I tried that showed them in use in a residential setting between wooden floor joists. Hoping someone here will have an example or does everyone just talk about how great it would be but never actually does it? It makes sense that it would be an "improvement" but logically doesn't seem like much as I would think the 1/2in drywall ceiling would burn up way before any sort of fire would spread from one end of my house all the way to the other where the bedrooms are located and by that point would already have gotten to where there are numerous other openings that are not sealed/fire blocked.

 

[peakbagger]

Do you happen to have a picture of how it is done with the dampers? I just could not find anything anywhere no matter how hard I tried that showed them in use in a residential setting between wooden floor joists. Hoping someone here will have an example or does everyone just talk about how great it would be but never actually does it? It makes sense that it would be an "improvement" but logically doesn't seem like much as I would think the 1/2in drywall ceiling would burn up way before any sort of fire would spread from one end of my house all the way to the other where the bedrooms are located and by that point would already have gotten to where there are numerous other openings that are not sealed/fire blocked.

No I do not have picture. All of the fire dampers I have installed are in commercial air handling systems where they are required by code.

 

[begreen]

Don't skip the fusible link damper. Atlanta Supply has what you need. I would try the one central register first. Make it a decent size, try something like a 24" x 12" to start with. Get an appropriate unrestrictive floor register with it.

AtlantaSupply

Atlanta Supply is now JEDCO Supply

www.atlantasupply.com

The stairwell will act like a cool air return so leave it open. FWIW, I doubt this will heat the far bedrooms much at all, but it should make a notable difference in the living room/DR/kitchen core.

 

[CT Burner93]

Don't skip the fusible link damper. Atlanta Supply has what you need. I would try the one central register first. Make it a decent size, try something like a 24" x 12" to start with. Get an appropriate unrestrictive floor register with it.

AtlantaSupply

Atlanta Supply is now JEDCO Supply

www.atlantasupply.com

The stairwell will act like a cool air return so leave it open. FWIW, I doubt this will heat the far bedrooms much at all, but it should make a notable difference in the living room/DR/kitchen core.

The stairway is wide open it's a split level ranch so it has a landing when you walk in from door and then down to lower level and up to main level. I'm not worried at all about heating the bedrooms (Personally like it cold when sleeping and would actually prefer if it didn't heat them). I would just like to be able to even out the heat a bit in the living/family room spaces so that it's not so unbearable downstairs and a bit warmer upstairs for anyone wanting to sit in the living room. Which location do you suggest in the floorplan I attached the one above the stove or the one towards the middle of the room closer to the stairs? I could also put a register instead in the corner of the dining room like in the attached image below? I've attached a picture of the current stove room/family room as well showing the 3 possible locations and also what the open staircase looks like. I've tried 2-3 fans blowing all the way down along the floors towards the stove but couldn't do better than 70 upstairs with 80-82 in family room.

 

[Simonkenton]

I have a log cabin 16 x 30 with an upstairs the same size. Conventional stairs going up.
My bedroom upstairs was too cold. I installed a register in the floor/ceiling right near the heater. A conventional 6 inch by 14 inch register.

It did not affect the cold bedroom at all.

Obviously, if you put in a big enough register the heat will go upstairs, but it has to be a whole lot bigger than 6x14.

 

[CT Burner93]

I have a log cabin 16 x 30 with an upstairs the same size. Conventional stairs going up.
My bedroom upstairs was too cold. I installed a register in the floor/ceiling right near the heater. A conventional 6 inch by 14 inch register.

It did not affect the cold bedroom at all.

Obviously, if you put in a big enough register the heat will go upstairs, but it has to be a whole lot bigger than 6x14.

I wouldn't want to heat the bedrooms just even out the temperature in living room/dining room/kitchen area with the lower level family room. Just would want to help air circulation as it seems air gets a bit "trapped" in the lower level and isn't able to circulate upstairs easily.

 

[begreen]

My first inkling is to try the more central location, toward the stairs. I just gave an example size. If however, the floor joists run parallel to the short walls and are 16" on center, you might choose a different configuration to fit between the joists like a 14x20.

 

[CT Burner93]

My first inkling is to try the more central location, toward the stairs. I just gave an example size. If however, the floor joists run parallel to the short walls and are 16" on center, you might choose a different configuration to fit between the joists like a 14x20.

The joists run parallel to the stairs so the shorter walls of the house so not sure if a large register would fit would probably have to go smaller like you suggest if do it in the middle. You don't happen to have any sort of pictures or know of anyone that posted any showing a register with the fire damper inside? Just trying to get a general idea of how it looks/is done.

 

[peakbagger]

I will not guess where to put them. My experience with friends is they cut a hole in the coldest corner of the room and pump the air out with a fan to lower level. If you depressurize a room with a fan, the hot air will flow to it. Heat only rises if cold air can drop. Fans move more mass of air when cold so you get biggest bang for your buck moving cold air around.

The fire damper is mounted under the floor between the joists making sure the linkage is free is the fusible link burns. The sheetmetal part is what you will need to fab up. its a very short length of duct preferably with a fixed flange on one end and slide on flange on the other end. A hole is cut through the floor to fit the duct and the duct is slid down through the hole. any gaps are fire caulked. The duct is held in place by the upper flange. The grate gets screwed down over the duct opening. Then the other end of the duct is attached to the fire damper. Unless you have a finished ceiling below you are done but otherwise you need to make another short piece of duct to go through the lower ceiling and finish off with ceiling grate.

Attached is my crude sketch

 

[CT Burner93]

I will not guess where to put them. My experience with friends is they cut a hole in the coldest corner of the room and pump the air out with a fan to lower level. If you depressurize a room with a fan, the hot air will flow to it. Heat only rises if cold air can drop. Fans move more mass of air when cold so you get biggest bang for your buck moving cold air around.

The fire damper is mounted under the floor between the joists making sure the linkage is free is the fusible link burns. The sheetmetal part is what you will need to fab up. its a very short length of duct preferably with a fixed flange on one end and slide on flange on the other end. A hole is cut through the floor to fit the duct and the duct is slid down through the hole. any gaps are fire caulked. The duct is held in place by the upper flange. The grate gets screwed down over the duct opening. Then the other end of the duct is attached to the fire damper. Unless you have a finished ceiling below you are done but otherwise you need to make another short piece of duct to go through the lower ceiling and finish off with ceiling grate.

Attached is my crude sketch

So the fire damper is just attached to two pieces of fab duct on each side and basically "floats" in place? Or is the fire damper screwed/nailed into the joists at all? When you say its held in place by the upper flange is this going to be tacked into the floor above or how exactly does this hold everything in place? I would want a flush wood grate with my wooden floors and wouldn't want anything sticking up/ontop of the floor above. Is this possible with a fire damper? Videos I was able to find of people installing floor registers they just slid in piece of duct and then nailed it to the sides of the joist inside the hole. Would that work or it needs to have a flange outside of the hole to hold everything from falling down the hole?

 

[Shrewboy]

Do you happen to have a picture of how it is done with the dampers? I just could not find anything anywhere no matter how hard I tried that showed them in use in a residential setting between wooden floor joists. Hoping someone here will have an example or does everyone just talk about how great it would be but never actually does it? It makes sense that it would be an "improvement" but logically doesn't seem like much as I would think the 1/2in drywall ceiling would burn up way before any sort of fire would spread from one end of my house all the way to the other where the bedrooms are located and by that point would already have gotten to where there are numerous other openings that are not sealed/fire blocked.

The reason I read about why the automatic fire damper is important is because the open register hole allows air to rapidly and directly move from the lower floor to the upper one.

so if there is a fire, the smoke and very hot air will rush through the register, feeding the fire oxygen and helping it to spread quicker.

(In my personal and unprofessional opinion it seems counter intuitive because if this was such a concern, shouldn't open floor plans and open balcony staircases be a big safety concern? lol)

I was thinking of putting one of these registers in myself with a fire damper. If I do it, I will include it in my post about my new wood stove / custom hearth and backer build.

 

[peakbagger]

The intent was to show you a concept not give you an architectural detail.

I do not know what size and thickness grate you are planning to buy or what type and thickness of flooring and subflooring. If I put one in my living room floor I would want a flush grate. I have 3/4" hardwood strip flooring so I would carefully figure out if there are any hidden flooring nails through the plywood subflooring and then using my router I would put in recessed stepped lip in the flooring for the edge of grate and the upper flange of the duct work. After I got the recesses routed and the corners chiseled out, I would ease the upper edge of the recess with small radius cutter to "ease" the upper edge. The grate would obviously be larger than the flange on the duct. That would give me the subfloor to drill down into to run some screws to hold everything tight. I would then cut a hole the size of the duct down through the remaining hardwood and the sub floor. Then as you surmised the duct would be slid down the hole and the flange secured to the remaining hardwood and underlying subfloor. Unless you cut things real tight, fire caulking can be used to fill the gaps and tighten things up. The grate is then dropped down on top of it into the larger recess and its screwed down. The duct is now hanging down under the floor. I dont have a fire damper in hand so you wll have to fill in the detail on how it connects to the new short piece of duct. It may be flanged or it may be butt strip joint. Heck a sliding fit and pop rivets may be the easiest and with fire caulk if you have gaps they are easy to fill. It doesnt weigh much and I expect the duct flange screwed to the flooring and subfloor above will hold its weight or you can easily run some steel strapping to the joists.

Be aware that once you cut in grate its there forever as its PITA to patch the floor if you ever remove it. I might suggest starting with the least obvious one to get your technique down.

 

[CT Burner93]

The reason I read about why the automatic fire damper is important is because the open register hole allows air to rapidly and directly move from the lower floor to the upper one.

so if there is a fire, the smoke and very hot air will rush through the register, feeding the fire oxygen and helping it to spread quicker.

(In my personal and unprofessional opinion it seems counter intuitive because if this was such a concern, shouldn't open floor plans and open balcony staircases be a big safety concern? lol)

I was thinking of putting one of these registers in myself with a fire damper. If I do it, I will include it in my post about my new wood stove / custom hearth and backer build.

Yeah I personally don't see the big issue with it especially in a residential setting. I can see if you were cutting an open hole above your stove/heating appliance directly into your bedroom but people have entire open concept floors like you said. If you do decide to do it please post any pictures as i've yet to actually see one where someone did put in a fire damper.

 

[DuaeGuttae]

Our former home was a raised ranch, and we had a fireplace insert in the basement family room. After a few years we did end up cutting three vents in our upstairs open dining area/living room, and it did help with heat circulation. We had an open staircase from the basement to a foyer, but in our case there was a beam that bisected the house, and it created a barrier that kept the very hottest air trapped on the far side of the basement ceiling. We cut two vents by the side of that beam and one at the far end of the room. We did hire someone to do the cutting of our ceiling/hardwood floors and the fitting of sheet metal. We also chose places that were quite unobtrusive--behind a chair in the corner of the living room and along a wall flanking a passageway from the kitchen to the dining room. All three grates were 6" by 14", and we normally let them work just naturally. In really cold spells we put a fan blowing down in the far grate and perhaps one blowing up in one of the near ones.

I've read that a lot of people don't have success with grates, so I would take my time in making the decision. We spent a lot of time studying the airflow in our house (taping up tissues, walking around with them, pointing an infrared thermometer at the ceiling to see where the hottest air was) before deciding. In our case it worked, but I think it was in large part because we had so much hot air trapped by that lowered part of the basement ceiling.

Our insert extended about ten inches from the front of our fireplace, and while there was a lot of heat directly above it, we deliberately avoided putting a grate in that spot. We had young children and never wanted one to drop something through the registers onto a hot stove. (To my knowledge they never dropped anything through the registers at any time, but we didn't want to take the chance.)

 

[begreen]

Yeah I personally don't see the big issue with it especially in a residential setting. I can see if you were cutting an open hole above your stove/heating appliance directly into your bedroom but people have entire open concept floors like you said. If you do decide to do it please post any pictures as i've yet to actually see one where someone did put in a fire damper.

I think the intent is not to stop the fire, but to buy the occupants time. A minute or two can make a very big difference in getting out of a burning house.

 

[CT Burner93]

I think the intent is not to stop the fire, but to buy the occupants time. A minute or two can make a very big difference in getting out of a burning house.

Totally get that all for more safety, just the more I think about it I don't really see how a fire damper on a floor vent on the opposite end of the house as the bedrooms with a wide open split level staircase in the middle and drywall ceilings is of any real help in buying any time. I feel lining the hole with sheet metal would be what's really protecting the joists from horizontal fire spread which seems the bigger danger. Whenever I do go to cut any vents though i'll certainly put one just to say I have it and for the peace of mind, but from a logical standpoint just seems like more of a feel good thing.

 

[CT Burner93]

Our former home was a raised ranch, and we had a fireplace insert in the basement family room. After a few years we did end up cutting three vents in our upstairs open dining area/living room, and it did help with heat circulation. We had an open staircase from the basement to a foyer, but in our case there was a beam that bisected the house, and it created a barrier that kept the very hottest air trapped on the far side of the basement ceiling. We cut two vents by the side of that beam and one at the far end of the room. We did hire someone to do the cutting of our ceiling/hardwood floors and the fitting of sheet metal. We also chose places that were quite unobtrusive--behind a chair in the corner of the living room and along a wall flanking a passageway from the kitchen to the dining room. All three grates were 6" by 14", and we normally let them work just naturally. In really cold spells we put a fan blowing down in the far grate and perhaps one blowing up in one of the near ones.

I've read that a lot of people don't have success with grates, so I would take my time in making the decision. We spent a lot of time studying the airflow in our house (taping up tissues, walking around with them, pointing an infrared thermometer at the ceiling to see where the hottest air was) before deciding. In our case it worked, but I think it was in large part because we had so much hot air trapped by that lowered part of the basement ceiling.

Our insert extended about ten inches from the front of our fireplace, and while there was a lot of heat directly above it, we deliberately avoided putting a grate in that spot. We had young children and never wanted one to drop something through the registers onto a hot stove. (To my knowledge they never dropped anything through the registers at any time, but we didn't want to take the chance.)

Sounds very similar to my house. What type of company did you have come out to cut the holes/line with sheet metal? Was it a flooring company or HVAC or both? Did you have them install the fire dampers in each of them or no?

 

[kennyp2339]

I think the intent is not to stop the fire, but to buy the occupants time. A minute or two can make a very big difference in getting out of a burning house.

Theoretically your correct in that assumption, but the smoke produced will get you way before any fused damper closes, those fused dampers are great for commercial hvac applications and town home / condo building applications, single family residential, its kind of like peeing in the wind, especially for a static vent (no mechanical fan assist)
Take a look around your own house, see how many things you own are made of plastic, essentially as we are taught in the fire service, all plastic things are like having buckets of gasoline laying around.
The best thing any homeowner can have is a sprinkler system installed (actual building code in some states for new stand alone single family residential structures) the second best thing is good smoke detectors.

 

[begreen]

Most homes do not have sprinkler systems. Agreed that the first line of defense in the average house is good working smoke detectors. The second is slowing down the flame spread.

 

[peakbagger]

FWIW I have met several folks who built homes in rural towns or unorganized townships that were unable to insure their new home/"camp" unless they installed a sprinkler system. These towns and townships do not have fire departments at all or they have minima gear or staffing. In the town where my woodlot it located they have a couple of fire trucks and three active firefighters. The town has mutual aid with adjacent towns but the reality is that by the time they respond to a structure fire its probably too late to save it. Most of the town is old summer homes but all new construction requires sprinklers.

 

[DuaeGuttae]

Sounds very similar to my house. What type of company did you have come out to cut the holes/line with sheet metal? Was it a flooring company or HVAC or both? Did you have them install the fire dampers in each of them or no?

It wasn't either a flooring or HVAC company but a contractor who worked in home repairs and remodeling and did have some experience with both. We had worked with him when we finished out part of an unfinished part of our basement to become an office for my husband, and he seemed like a person who would be willing to work with us on the unusual request.

We did not install fusible link dampers. Before we cut the vents, we talked with the code inspector for our city in our house (he was out completing an inspection for something else--it was the type of place that needed permits for everything), and he said that they were not required or helpful in our setting with a big open staircase in the same room as the woodburning apppliance. He was most concerned about our having working smoke and carbon monoxide detectors, which we did. (It was basically the same explanation that @kennyp2339 has been giving.) I do think that many states have adopted an updated national code in more recent years, and I cannot say what may be required now. I only know what I was told then.

Floor vents worked well enough for us in our old home that we've even considered whether we would want to do something similar in our new home. We haven't committed to it yet, and it's less likely that we will do it here since we've just installed solar panels and expect to have some extra kilowatts during wintertime which will allow more space heating.

If you are thinking about cutting vents, be aware that they also do allow a bit of noise to travel. It was not ever a problem for us, but it's just something to think about.