Floor registers, dampers and insulation

[burlsube]

I am thinking of installing some floor registers in my house to encourage air movement. I have an old (1800's) Cape style house with a PE Vista insert installed on the first floor. I am looking to install a vent on the far side of the house to get some air movement to the master bedroom. The master bedroom is on the top floor and it gets pretty breezy in the winter... it dips down into the 40s. There is no heat in that room.

I'm going to use the original holes got the vent. My question is at some point a previous home owner insulated between the first and second floor. If I simply put a vent in between floors I will be exposing both rooms to the fiberglass insulation.

How can I minimize the exposure to insulation. I get particularly itchy when around insulation and I dont like the idea of just a hole surrounded by loose insulation. I was thinking of using a fire damper between the floors, but the floors are deeper then all of the dampers made. What are my options?

 

[begreen]

A metal sleeve (basically a short metal duct) could be installed between the floors.

I'm wondering if this plan will work? The insulation between the floors was a bad move from the sounds of it. It's going to take a lot of convection to get around this problem. We need to know more about the house floorplan to make a good suggestion. Would it be possible to post a plan of both floors or at least a sketch of them?

 

[KB007]

Check you local building codes carefully. It sounds like you are going through the main floor cieling which is an enclosed space. To do this you most likely require a full metal duct and in many areas a fusible damper that will close in the event of a fire. I'd alos suggest you look at more than 1 register, you need 1 to let the cold air drop and one to let the hot air rise.

Pics, or a floor plan would be helpful

 

[burlsube]

Thanks. I'm not too concerned with the codes. The house is old and has other code violations I'm sure -- a tree trunk is currently holding up the first floor. I am absolutely going to install duct with fusible link. I'll work on trying to sketch out layout.

Would the 2nd register need to be in the same room as the first or just on the same floor?

 

[pen]

When considering registers remember what goes up must come down.

If you want hot air to rise cold air need to sink somewhere to take it's place. W/out a cold air return it just won't rise.

Glad to see you are going to use fused dampers if you decide to do this.

pen

 

[burlsube]

Can a fusible damper be placed within a metal duct? Also, are there any resources to make/purchase ducts. The big box stores around me dont have anything with the correct height...

 

[michaelreinard]

FWIW I was looking at fire dampers for my project, and found these:
http://www.grainger.com/Grainger/DAYTON-Rectangular-Fire-Damper-2TGD3

I believe they are designed to be place inside duct work. There are several other size dampers available on the site - just note that they come in two varieties, vertical and horizontal, and can be classified as static or dynamic and you probably want the static ones for a project like this.

Can someone tell me - if you are using one of these dampers, are you allowed to have your vent within 10 ft of the stove? Anybody know how they measure that, that is, is it 10 ft horizontal (so I can't count the 5-6 vertical ft above the ceiling)? I have asked this before, but haven't gotten anyone to opine.

Thanks,
Mike.R

 

[VCBurner]

Hello burlsube,

I'm no hvac expert, but as a union carpenter, we end up working closely with the hvac guys on most jobsites. I agree with what pen said. HVAC systems work with a supply and return. This means that a register may not necessarily work as a supply of warm air to the upstairs but a return of colder air to the downstairs. Which does not mean that they won't make a difference or work in getting the heat upstairs quicker. If the stove is near the stairs that lead up to the second floor, they will most likely be the main supply of warm air to the upstairs. Leaving the doors open to the cold bedroom upstairs will be essential. The register should be in the opposite side of that room's door. The cold air in that room will then be sucked down to the stove room through the register thus pulling in the warm air from the hallway upstairs. As far as the insulation, it is a good thing. It just means that you won't be loosing as much heat between the floors. Covering the register "duct" openning with sheetmetal to cover the insulation will do the job or even sheetrock (though sheetmetal is probably the correct material to use.) Wear long sleeves when doing the job and coat your arms with baby powder to prevent any fiberglass from entering your skin pores. There are also tyvek suits that can be purchassed if you're really serious about protecting yourself. They are simple and very commonly used by painters and insullators. IMO the fire damper idea is a good one, there is nothing better than being safe when dealing with fire prevention. This is another issue we deal with on a day to day basis in commercial construction. The residential end of construction is a bit slower to convert to the strick fire codes we see in commercial buildings. How often do you see fire sprinklers in people's homes? I believe lots of lives would be saved if we had at least one sprinkler in each floor. Main hallways or stairwells would be a good start. Currently the only sprinkler you see in people's homes are in front of a furnace. They are pretty simple to install and could save lives.

 

[burlsube]

@VCBurner thanks for the good information. Any idea where I can get a square duct or are they easily made?

 

[begreen]

Usually they are fabricated with a 1/2" flange on one end and raw on the other for the final fitting. But if you just have one it could be fabricated on site if you have some sheetmetal skills and some tin snips.

 

[VCBurner]

@VCBurner thanks for the good information. Any idea where I can get a square duct or are they easily made?

Like BeGreen said, you may be able to find them pre made at the big box stores. You can also get in touch with a local sheetmetal shop and see if they have something that'll work for you, they usually have a bunch of stuff already made you may walk out with a piece of duct. The third option is to make one yourself, just make sure you use red snips, otherwise you'll end up injured :gulp:.

BTW, welcome to Hearth.com!

 

[michaelreinard]

I didn't realize you were asking about the duct and not the firedamper.

This might be helpful to you, as they have several sizes (great site to buy off the beaten path materials, but from my experience they'll nail you on the shipping).
http://www.mcmaster.com/#additional-ductwork/=e8dy6i

Can I ask where you are getting your fire damper burlsube? Are the prices similar to those in the Grainger link that I provided earlier?

Thanks,
Mike.R

 

[burlsube]

I was planning on getting it from Grainger. They had the best prices. I'll check out McMaster now...

 

[michaelreinard]

I just noticed on McMaster that they had fire dampers on there too. Let us know how it goes!

Mike.R

 

[burlsube]

Will do. Looks like the hardest part will be getting the duct.

 

[pen]

If there is a metal shop around or a buddy with a break it wouldn't be hard to have one fabricated if you can't find the duct you are looking for.

pen

 

[DiscoInferno]

I have a single duct w/ damper almost directly above my Napoleon, which serves to heat my office above. The "return" in this case is the house's main stairwell. Circulation is excellent, so much so that I never bother to install the second damper I had bought. I got my damper and registers at http://www.atlantasupply.com/. I built the short rectangular duct/sleeve from home depot sheet metal. Note that the damper instructions call for a much thicker gauge than is available at HD or is workable with snips. I tried to follow the spirit of the damper install instructions, which call for the damper to "float" in the ductwork by using brackets to clamp around the surrounding fireproof wall/ceiling. But since in a residential ceiling this just means 1/2" drywall, it's not really sensible. For me it's a safety rather than a code issue, as the code inspector himself suggested I cut a hole for this purpose and said he wouldn't even bother with the damper. I have a smoke alarm and CO alarm directly above the register in my office, so hopefully that would go off even before a fire got to the point of tripping the damper.

Link to my original thread and some pics: https://www.hearth.com/econtent/index.php/forums/viewthread/43470/