insulation between floors?

[Scott Schultz]

Did an inspection today on a 2 story house in which the space above the first floor (kitchen, living room, etc...) had no insulation. The attic upstairs had R-30 cellulose. What's the consensus on insulation between the first and second floor?

[Larry D. Kage]

Originally Posted by Scott Schultz

Did an inspection today on a 2 story house in which the space above the first floor (kitchen, living room, etc...) had no insulation. The attic upstairs had R-30 cellulose. What's the consensus on insulation between the first and second floor?

It is not needed. That area is not part of the building envelope.

I suppose, for sound deadening, a case could be made.

[James F. McKee]

as Larry said only used for sound as in the case of rental unit separation....

[Marcel R. Cyr]

Agreed and as Jim pointed out for rental units, sometimes it is also wise to insulate the second floor to retain the heat on the first floor unit when the two apartments have seperate heating units, and responsible for their own heat.
One would be surprised at the heat loss from the first floor to the second.

Other than that, not required.

[Joe Funderburk, CMI]

Should there be insulation between interior walls?

[cboyd]

"One would be surprised at the heat loss from the first floor to the second."

You got that right Marcel, we actually don't heat our second floor in my 140 year old farm house, it just sucks up the heat from the first floor and stays quite comfortable for the most part. I have to replace the heat on the first floor on a pretty regular basis though $$$

[Nick Gromicko]

In a home I built for myself, not only did I not insulate between the first and second floor, I didn't have any heating on the second floor at all. The second floor relied solely on the heat from the first floor rising.

[rspermo]

While I agree you do not need to insulate between the floors you do need to have an air barrier and insulation at the end of the joists (rim board) to prevent air flow between the 2 floors.

[Marcel R. Cyr]

That is correct and seldom done in older homes. IR camera is about the only way to find out.
In the winter time, you could use an IR Thermometer also and shoot the ceiling perimeters and the field of the ceiling and walls for comparison.

[Joe Funderburk, CMI]

Originally Posted by gromicko

In a home I built for myself, not only did I not insulate between the first and second floor, I didn't have any heating on the second floor at all. The second floor relied solely on the heat from the first floor rising.

What kind of rooms did you have on the 2nd floor. By c^de, all habitable rooms are supposed to have a source of heat.

[Marcel R. Cyr]

Joe, it did, just not like you see it today. It had radiant floor heating.

He also probably had floor registers to radiate heat in the space like I had in my Fathers home back in the 50's till the mid 60's when it got changed to oil heat.
Met code back then. If there was one.

[Nick Gromicko]

I had all bedrooms upstairs. It violated code but I didn't care. It worked great.

[Roy D. Cooke, Sr]

Originally Posted by mcyr

Joe, it did, just not like you see it today. It had radiant floor heating.

He also probably had floor registers to radiate heat in the space like I had in my Fathers home back in the 50's till the mid 60's when it got changed to oil heat.
Met code back then. If there was one.

Floor register to let the heat Up ???????
.
I thought these where so the Kids could lay on the floor and hear what mom ,dad and their friends where saying .

This was great place to hear all the stories they talked about .

[Marcel R. Cyr]

Originally Posted by rcooke

Floor register to let the heat Up ???????
.
I thought these where so the Kids could lay on the floor and hear what mom ,dad and their friends where saying .

This was great place to hear all the stories they talked about .

Yeah, you could hear if having to get a twitch in the woods was in the forecast for something you might have done wrong.
Worked great for heat too!, all the way from the wood furnance in the basement.
I got to be a pilot because of that wood furnance at a very young age.

[Kenton H. Shepard, CMI]

Originally Posted by lkage

...I suppose, for sound deadening, a case could be made.

Sound travels through framing. Insulating walls and ceilings makes very little difference in lowering sound transfer. A long time ago I once recommended insulating between ceiling joists to lower sound levels. It made almost no difference and they were not happy with me.

Often when we framed library and sometimes bedroom walls, in each wall we used 2x6 top and bottom plates and two sets of 2x4 studs, each set held flush to opposite sides of the plates and each set offset from each other.