Energy Usage, Conservation and Weather Stripping - Conserve Heating Oil with Lower Ceiling?

Im trying to reduce my home heating oil bill. I have a living room that is 12' x 12'. It has a vaulted ceiling, straight up at one end and at a 45° angle at the other. 17' at the high end, 9' at the low end. There are 2 beams the tops of which are also 9' from the floor and 8' from the peak. There is roughly 1150 CFT from the tops of the beams up. Thats a lot of space to let expensive warm air to fill. How effective would it be if I got a roll of heavy poly and just made a 'false ceiling' on top of the beams, wall to wall?

Thank you. Thank you very much.

Hi super, it does get warm up there, I have had to work in areas like yours and sweat bullets. But the actual BTU's lost is another question. What you would be changing would be the heat lost through all upper surfaces that are exposed to the cold outside. If those walls and ceilings have good insulation, then your savings will be minimal (not worth the effort). If you have no insulation, or very little, isolating the heat from that area would reduce the heat loss, but could promote condensation and mold.

Sometimes a fan is installed to circulate that warm air back down to where it can be appreciated, but the resulting draft will feel cooler and the increased air flow will increase the heat loss through the walls and ceiling.

IMO, best to look elsewhere to find some savings. Shrink plastic on windows has proven to work well and be very cost effective. Air sealing in basement and attic can be easy and greatly reduces the air lost from the house.

Lots more suggestions if needed.

Bud

Poly will have no real R-value so it might save you a few dollars for a season. A ceiling fan would help you out more.

Hi super, it does get warm up there, I have had to work in areas like yours and sweat bullets. But the actual BTU's lost is another question. What you would be changing would be the heat lost through all upper surfaces that are exposed to the cold outside. If those walls and ceilings have good insulation, then your savings will be minimal (not worth the effort). If you have no insulation, or very little, isolating the heat from that area would reduce the heat loss, but could promote condensation and mold.

Sometimes a fan is installed to circulate that warm air back down to where it can be appreciated, but the resulting draft will feel cooler and the increased air flow will increase the heat loss through the walls and ceiling.

IMO, best to look elsewhere to find some savings. Shrink plastic on windows has proven to work well and be very cost effective. Air sealing in basement and attic can be easy and greatly reduces the air lost from the house.

Lots more suggestions if needed.

Bud

I keep the thermostat pretty low, the digital thermometer usually reads 60 degrees on that floor in the winter (the floor below that is the above ground basement, not heated except for the furnace itself ) the interior temperature is so low sometimes the pipes freeze (yes theyre too close to the exterior wall, against code) I know the roof has lousy insulation. Yes, the other side of the sheetrock is probably relatively cold. But since the poly wouldnt 'seal' that space, there would still be air exchange so in effect it would only be keeping some of the heat that filled vaulted space down in the living area, reducing the amount of oil burned to keep the temperature in the living area at a constant, no?

I use shrink plastic on the windows, the first time I used it, there was a noticeable difference - I could keep the thermostat lower for the same room temperature. I've sealed the exterior of all the window frames with silicone caulk. The floor of the peaked attic also had old, decrepit R-19 in the bays. I added one layer of R-25, comes in rolls inside a thin plastic wrapper, on top of the R-19 down the length of the floor, perpendicular to the bays. I filled the voids in the 2 door frames from the basemant to the garage with insulating foam sealant (Great Stuff) Also all around the new skylight I put in the bathroom, the new Thermatrue's entryway door frame and any other voids I could find. I also put a double paned storm/screen door on the entryway. The living area is above the small attached garage, when I pull in and close the overhead door, I open the car's hood and put all that residual engine heat to use!


Poly will have no real R-value so it might save you a few dollars for a season. A ceiling fan would help you out more.

Plastic curtains are used to keep cold air from escaping/warm air entering large walk/drive in refrigerated areas, like in warehouses. No R-value, but wouldnt it just prevent heated air from filling that whole space? And part of the problem and the reason for the question is budget is too tight to buy fans, foam insulate the attic or put up vinyl siding with the foam behind it. A fan would be nice, if only I did it a few years ago when I considered it, cant afford the cost now. :( But as Bud said, it might do the opposite.

Yes, the other side of the sheetrock is probably relatively cold.

Where is the sheetrock? The vaulted ceiling is sheetrocked?, and you are refering to the void/minimally insulated area above it, that is likely cold?

But since the poly wouldnt 'seal' that space, there would still be air exchange.....

An air exchange, how? From a partial sheeting job?

.....so in effect it would only be keeping some of the heat that filled vaulted space down in the living area, reducing the amount of oil burned to keep the temperature in the living area at a constant, no?

You aren't going to fully poly sheet the LR? Just partially, some how?

Obviously this would be a rather unique cobble job. It probably would not meet any code standard from having that plastic sheeting exposed, in case of fire. And may null and void an insurance policy. That be my guess anyway. And certain plastics may give off poisonous gas.

I use shrink plastic on the windows, the first time I used it, there was a noticeable difference - I could keep the thermostat lower for the same room temperature.

Materials that are non-conductive and not very dense(the opposite say of highly conductive copper clad cookware) are bound to slow the speed of heat transfer, at least some. And when it does, the extra dead air space it creates, helps.

But one of the primary reasons why the ultra thin shrink wrap has such a noticeable effect is it stops all air infiltration. Even some of the new vinyl windows let air through the different joints. A complaint we have gotten from some tenants. And to think that was the idea why we changed out the old wooden windows for these. It is pretty hard to stop any air from getting in anything with moveable parts, when you have some nights way below 0, with the wind howling 30 or so mph. And they even shrink wrap them.

I conducted an experiment last night. I fairly quickly, steadily, moved my hand toward my electric space heater to feel how hot my hand got. Then, I put my hand inside one of those plastic grocery store bags and tried it. It did not slow the heat transfer hardly at all! Then I put my hand inside 2 bags. Better. Then I ripped off a plastic label from a 2-litre pop bottle and put my hand behind it. That felt like it took the longest, for my hand to get hot.

We do know that certain thin substances act as a heat barrier. Take latex gloves. Ever use them to do dishes with 100% hot water? You can do it. These insulate quite well. Probably microscopic air pockets are entrained in that latex is my guess.

If I were you, I'd do a similar experiment with your poly sheeting, as long as I think your mind is set on doing this. All this experiment will take is a few minutes.

Your question specifically asks how effective would a plastic barrier be in reducing your heating bill.
My opinion is it would have little or no impact on your bill.
In addition to being a waste of time it would be very unsightly and a major fire risk.

There is a certain amount of stratification that occurs in a room like yours but there will also be some natural convection going on as well.
Your plastic would eliminate this and possibly have a negative impact on trying to save money.

You are on the right track in trying to seal up the house and add insulation where ever you can afford.

By the time you purchased 6mil poly and tape you could have purchased a couple of cheap fans.

A ceiling fan would be best. Run it so it blows towards the ceiling to minimize feeling the air blow across your skin. If that is out of the budget, consider a small floor fan and aim at the ceiling to circulate the air that way.