[lper100km]

CD: - your website reference is an IT company!

[Crazy_Dad]

CD: - your website reference is an IT company!

Sorry - Fixed now

[SpringCreekFarm]

I heat my 854 sqft house with a single woodstove in the basement. I'd like to finish the basement ceiling to cut down on the noise. I want to use rock-based 'safe and sound' inslation in the ceiling but I'm afraid it will screw up the heating balance of the house by containing too much heat downstairs and prevent it from moving through the floors to the upper level of the house.

In this case I'm hoping the thermal quality of this sound insulation is bad.

Anyone have any input on this?

[lper100km]

Slightly OT maybe, but I think is relevant.

A lot of thought and effort goes into air sealing and insulating the structural frame, but in older houses at least, the chimneys are a huge source of heat loss. When unlit, the cold outside air can move down into the house and when lit, the house air is drawn up the flue, requiring cold outside air as a replacement. The solution to both problems is to install a sealed gas or wood burner that uses outside air as combustion air and cycles the inside air through a heat exchanger. Some percentage of inside air has to be replaced in any case to maintain air ‘freshness’. Of course this relies on a fan and electricity, though a smaller house may be OK with a radiant/convection system.

[Pops]

Anyone have any input on this?

I don't know about that type of insulation but what you could do is use "Z-Bar" to install drywall on the ceiling. The drywall adds mass for thermal storage and the z-bar is a hinge that also lets the drywall mass deaden sound.

Here's a pic, one flange is screwed to the joist or stud and drywall is screwed to the other.


http://www.justaskjon.com/jons-fixit-da ... brief-tour

[Ludi]

I heat my 854 sqft house with a single woodstove in the basement. I'd like to finish the basement ceiling to cut down on the noise. I want to use rock-based 'safe and sound' inslation in the ceiling but I'm afraid it will screw up the heating balance of the house by containing too much heat downstairs and prevent it from moving through the floors to the upper level of the house.

In this case I'm hoping the thermal quality of this sound insulation is bad.

Anyone have any input on this?

Personally, I think you'd need to put some registers through from the basement to the first floor to make sure warm air can rise into the main house. These could have covers for when you don't want air to mix from the two spaces. But of course sound will move through the registers as well as warmth.

[SpringCreekFarm]

Pops and Ludi;

Thanks for the suggestions.

I use the old oil furnace and existing ductwork to channel the warm air from the basement to the upper floor on really cold days. I blocked the cold air return ( source air for old non-functional furnace ) upstairs and diverted it to suck up the warm air from downstairs and force it through the vents. So far, my air return is the basement stairs.

I'm going to just go ahead and try it out and see. The folks at the lumber store tell me that using the rock-based sound insulation is NOT good for thermal insulation so I guess that is my answer. Thanks again.

[davep]

SCF, you may find that rock-based insulation between the basement and the house could be very good thermal mass, slowly radiating heat into the ground floor. But I'd need to know more about what you intend using. Something based on clay would be ideal for retaining heat. You certainly shouldn't need any kind of heat insulation between the two, given your heat source is below ground.

[SpringCreekFarm]

Hi Dave...the stuff is called Safe N Sound here in Canada. I think you make a good point regarding the thermal mass of this stuff. Here is what I found...

http://www.kentinternational.ca/brochur ... d_tech.pdf

"General Product Information:
ROXUL® products are mineral wool fibre insulations
made from basalt rock and slag. This combination
results in a non-combustible product with a melting
point of approximately 2150°F (1177°C), which gives it
excellent fire resistance properties. ROXUL mineral
wool is a water repellent yet vapour permeable
material."

[greenspree]

SCF, you may find that rock-based insulation between the basement and the house could be very good thermal mass, slowly radiating heat into the ground floor. But I'd need to know more about what you intend using. Something based on clay would be ideal for retaining heat. You certainly shouldn't need any kind of heat insulation between the two, given your heat source is below ground.

Mineral wool (or rockwool, common brand name Roxul) is mostly air, as are all batt insulations and will provide very little thermal mass. Thermal mass also has no effect on heating costs if you are paying for your heat source, only if the mass is collecting free heat (i.e. solar heat) and releasing it when needed.

Heating an unused basement is very wasteful and I would recommend insulating between living and non-living spaces.

[greenspree]

I'm going to just go ahead and try it out and see. The folks at the lumber store tell me that using the rock-based sound insulation is NOT good for thermal insulation so I guess that is my answer. Thanks again.

Roxul (I believe that is what you are referring to) has a listed R-value (resistance to conductive heat transfer) of 25 for a 140mm batt based on CCMC (Canadian Construction Materials Centre) testing compared to 22 for a 140mm batt of Owens Corning Fibreglass Pink.

So the folks at the lumber store don't know what they are talking about (and frequently don't when it comes to a lot of building materials, especially insulations).

[greenspree]

I just read the first post SCF wrote where he heats with a woodstove, not a furnace in the basement.

You certainly wouldn't want to insulate the floor if you heat with a woodstove but I would insulate the basement walls, or move the woodstove upstairs.