Vent in ceiling

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Bushels20

Feeling the Heat
May 20, 2018
421
OH
My split level home (in the stove room) has a square cut out between the floor joists with a register cover on both sides. This in theory allows warm air to funnel up to the bedrooms. It is located in a mutual foyer outside all 3 bedroom doors of the upstairs.

The heat does rise up from the stove room through the floor register, naturally. However i would like to try and push more air warm upstairs somehow; ideally though the floor hole/register.

I know that it is better to push cold air to the stove room. However, the house tends to naturally loop pretty well. If I could get more warm air upstairs via the floor register, I would be pushing the upstairs cold air back down (as a result).

I have some ideas:

1. There is electric nearby (within the floor vent) attached to a switch, downstairs. Install an attic fan/bathroom vent and draw warm air up from the stove room and blow it up through the floor vent upstairs? Or am I thinking incorrectly and I should reverse that and blow cold air from upstairs down into the stove room and allow the warm air to push up the hallway/stairs (see photos).

2. Install a small door way fan and push the could air back down the hallway/stairs (see attached photo) thus resulting in more rising heat up through the floor vent?

3. Our girls are discussing knocking out a wall between their two bedrooms. If I did this (it’s easy) I could cut another vent hole into the floor (where the wall used to be) and this would be directly above the stove room. But, no reason to do so if it’s not going to work.

Please send some other ideas if you have them. Anyone have any luck with these floor vent holes? This house was set up this way when we moved in. I did not cut the hole/install the register myself. When we moved in, you could tell there was at one point in time, a wood heater of some kind that was removed prior to us moving in. I suspect the floor vent was original to the house. Circa 1979.
 
The biggest concern with this type of setup is the spread of fire. A second concern would be smoke. Does the register duct have a fusible-link damper installed? If not, it should. I think a fan can not be installed in the duct between floor registers. That would be too much like a return air duct which needs to be at least 10 ft away from the stove.

(ps: no pics attached)
 
The biggest concern with this type of setup is the spread of fire. A second concern would be smoke. Does the register duct have a fusible-link damper installed? If not, it should. I think a fan can not be installed in the duct between floor registers. That would be too much like a return air duct which needs to be at least 10 ft away from the stove.

(ps: no pics attached)

Sorry, forgot the pics. I have attached them.

The setup is literally a cut out in the subfloor, between the floor joist and then through the stove room ceiling drywall. Then capped on each side with registers covers. The register upstairs can be opened and closed (completely) if that is what you mean by “fusible-link damper”. Aside from that you aren’t speaking my language.

There is no “duct work” involved here. Simply a pass-through between floors to (in theory) allow airflow from lower to upper.

I was thinking I could install the attic fan/bathroom vent in between the two vent covers. Either suck warm air up or push cold down...?

Photo 3 (taken from the stove room looking up to the upstairs) maybe help a little better and also show the electrical that passes through for what would be easy connection. Photo 1 is from the upstairs looking at the hole/register from the upstairs. Photo 2 is the hallway leading downstairs to the kitchen, living and dining rooms (which are one level above the stove room). House is a 3 level split for heating purposes and the insert is on level 1. Bedrooms on level 3.

Thoughts?
 

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The limiting factor for heat getting upstairs is the size of the register.

A fusible-link damper is sometimes called a fire-damper. The damper is spring-loaded to close in the event that fire melts the fusible link. There are also smoke and fire dampers that interconnect with a smoke detector that triggers it to close.

In this case something like a 12AH fire-damper should work.
http://www.atlantasupply.com/swscripts/NLNETUPD.OBJ?CO_ID=AS\&&REQR_TYPE=O&REQR_ID=NEW+CUSTOMER&AUTH_ID=+&&LOC_NO=001&NL_ORDER_NO=@VAR_NL_ORDER_NO_@&PROD_CAT_NM=Fire+Dampers&PC=A&SC=FD&REQUEST_ID=CCATSEL_AS2
 
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The limiting factor for heat getting upstairs is the size of the register.

A fusible-link damper is sometimes called a fire-damper. The damper is spring-loaded to close in the event that fire melts the fusible link. There are also smoke and fire dampers that interconnect with a smoke detector that triggers it to close.

In this case something like a 12AH fire-damper should work.
http://www.atlantasupply.com/swscripts/NLNETUPD.OBJ?CO_ID=AS\&&REQR_TYPE=O&REQR_ID=NEW+CUSTOMER&AUTH_ID=+&&LOC_NO=001&NL_ORDER_NO=@VAR_NL_ORDER_NO_@&PROD_CAT_NM=Fire+Dampers&PC=A&SC=FD&REQUEST_ID=CCATSEL_AS2


Seems simple enough to install and also a very smart idea.

So.....am I pi$$ing into the wind? Try and move air upstairs another way? Ultimately, it’s not like it’s cold up there. I can easily maintain 70s in the main living spaces and 60s upstairs. But if I could crank it up and get 68-70 up there in the coldest of days, the wife and girls would love it.
 
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Just a thought..... would a small computer fan mounted to the underside of the vent be of any consequence?

These fans move air efficiently and can be hooked up to a 12 volt wall wart. They are quiet and may not upset the overall air scheme in a house.

Probably too small to make a different but I don't think I've heard or read about them here yet.
 
A simple baseboard heater or oil-filled radiator might be more effective for those coldest days.
 
M
Just a thought..... would a small computer fan mounted to the underside of the vent be of any consequence?

These fans move air efficiently and can be hooked up to a 12 volt wall wart. They are quiet and may not upset the overall air scheme in a house.

Probably too small to make a different but I don't think I've heard or read about them here yet.

Maybe. But if the idea being that the overall size of the opening is ineffective to begin with, probably not worth it. Maybe actually better to close the opening, retain the heat and move it another way.
 
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A simple baseboard heater or oil-filled radiator might be more effective for those coldest days.

True. Just hate to start shelling out the Benjamin’s.

I remember as a kid we used kerosene heaters. They were great. We had a smoke event once as a kid and I am in the insurance industry as well, I’ve seen my share of incidents as an adult as well.
 
A happy wife and family is a good investment.
 
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We used to heat our rambler from an insert in the walkout basement. After a couple of seasons when we got more dedicated to wood heating, we cut vents from our upstairs to our downstairs. Two were near the stove alongside a ceiling beam where the hottest air got trapped. One was in the opposite corner of the room near an external wall to act as an additional cold air return. (The primary path for cold air was a big open staircase to the basement).

Our vents really improved the warmth in the upstairs living area, but that was because they freed air that was trapped by that huge beam in the basement. Our vents were near walls and outlets, and on occasion we experimented with putting doorway fans in them. I think our best set up ended up being running our downstairs ceiling fan near the stove on reverse. It helped push air up. Then we ran the small fan inside the return vent pushing cold air down.

Your vent appears to be in the middle of a walking path, so having a cord coming out would not be workable. (Ours was right beside the vent and behind an armchair.). What is downstairs under the vent? I’m wondering if you could put a fan that is capable of pointing straight up if you have one already, or if that would simply be in the way of another major walking route.

I wouldn’t give up on the vent without playing a bit with resources you have on hand (if any). You’re not going to get it to act like a furnace, but you know it does something, and I bet you could help it out pretty easily.
 
We used to heat our rambler from an insert in the walkout basement. After a couple of seasons when we got more dedicated to wood heating, we cut vents from our upstairs to our downstairs. Two were near the stove alongside a ceiling beam where the hottest air got trapped. One was in the opposite corner of the room near an external wall to act as an additional cold air return. (The primary path for cold air was a big open staircase to the basement).

Our vents really improved the warmth in the upstairs living area, but that was because they freed air that was trapped by that huge beam in the basement. Our vents were near walls and outlets, and on occasion we experimented with putting doorway fans in them. I think our best set up ended up being running our downstairs ceiling fan near the stove on reverse. It helped push air up. Then we ran the small fan inside the return vent pushing cold air down.

Your vent appears to be in the middle of a walking path, so having a cord coming out would not be workable. (Ours was right beside the vent and behind an armchair.). What is downstairs under the vent? I’m wondering if you could put a fan that is capable of pointing straight up if you have one already, or if that would simply be in the way of another major walking route.

I wouldn’t give up on the vent without playing a bit with resources you have on hand (if any). You’re not going to get it to act like a furnace, but you know it does something, and I bet you could help it out pretty easily.


Underneath the vent down stairs it is right along the wall. No walking space. Would not be in the way like upstairs.
 
We have a similar grated floor vent. It is in the stove room and goes up to our bedroom. I have played with a small 10 inch circular fan that can be tilted to blow down or straight up. I set it on the grate in the bedroom and let it suck the heat up. Then I tried blowing down. Setting the fan to suck the heat up seemed to have the most advantage. My vent is roughly one foot by one foot. Rather small. FWIW
 
We have a similar grated floor vent. It is in the stove room and goes up to our bedroom. I have played with a small 10 inch circular fan that can be tilted to blow down or straight up. I set it on the grate in the bedroom and let it suck the heat up. Then I tried blowing down. Setting the fan to suck the heat up seemed to have the most advantage. My vent is roughly one foot by one foot. Rather small. FWIW


Mine too is about 12” X 12”.
 
Sounds like grabbing a cheap little fan to play with may be worth your effort. I really only use it when it gets down to zero or less.
 
Cold air returns along the perimeter will help with natural convection
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The hot air will normally rise up from the stove to the ceiling, then up through the grate/vent. It continues rising and then falls down the staircase and eventually returns to the stove room. To verify the path when the stove is going hold a cigarette or freshly blown out candle (smoking is bad, don't start just for this test) near the vent and see what way the smoke moves. I would put a desk fan between the two grates pointing the direction of air movement (likely up). Control it with a air conditioning line voltage thermostat so that it will turn off when the stove is not producing enough heat.

As to the fused vent closure. Everything said is true. A fire can travel up and through an open vent. Fire can and will also pass up and through an open stairway, open vaulted second floor area and etc. Keep all the paths in mind as you evaluate the path a fire or smoke can travel through your home.