2 story, do you insulate in between or no?

[Husky79]

It's going to be a 40x88x17 Shouse, the shell will be built first, then build the 40x26 living space with 2nd floor that is more of a entertainment/guest room rather than daily uses. I am wondering if it would be worth it to put blown insulation in between the floor trusses before installing the floor on 2nd floor? The 1st floor will be slab heating, 2nd floor will be forced air heating.

 

[kj_mustang]

If using radiant on first floor, I would not insulate between floors. You can check my build thread but my place has two floors in half the building. No heat at all on the second floor and it averages only about 3-4 degrees cooler than the first floor. Exterior wall and roof insulation is key to that though.

 

[cannuck]

You might get away with no heating on second floor in VA but I sure wouldn't try that in MN!!!!

Insulation between floors would only be beneficial thermally if you wanted to maintain two different temperature zones - which might well be the case for occasional use. It will also help deaden sound, but not by very much as the floor joists can make a pretty good sound bridge.

 

[yeldogt]

Always insulate all interior walls/ceilings with simple batt insulation -- makes for a much quieter building and space.

 

[acer66]

Always insulate all interior walls/ceilings with simple batt insulation -- makes for a much quieter building and space.

This.

 

[FJ 432]

Always insulate all interior walls/ceilings with simple batt insulation -- makes for a much quieter building and space.

Totally agree for noise if you can afford it.

 

[duneslider]

I was going to say the same thing, insulate for the sound isolation.

 

[jack stand]

Not necessary between the floors of the "house" within the shell.
Definitely a noise reduction benefit in the interior separating walls if that's a concern.

 

[yeldogt]

If you add interior walls and ceilings to the insulation contract at build time it is surprising how cheap the upcharge .. Fiberglass insulation is cheap and the pros can put it up so fast -- no reason not to fully insulate for sound. When you price out the product -- it's surprising how little it costs to have it done. They buy the product at a lower cost and it's a pain to transport --- well worth paying for install.

 

[Dig Doug]

Yes insulate everything!

all walls interior and exterior, ceilings & floors ! Cool during summer and warm in winter! not to say anything about the sound improvements

 

[kj_mustang]

You might get away with no heating on second floor in VA but I sure wouldn't try that in MN!!!!

My winter temperatures consistently average in the low 30's down to single digits at times. No issues living full time in the place over the winter. Again, I insulated very well.

 

[mikedodge]

I was going to say do it for noise too. It doesn't matter as much for heat. Not many houses have insulation between ground floor and un finished basement.

 

[dogdog]

Yes Insulated in between... the noise travels on the thinner floor and ceiling materials than old lath days.

When I redo mine, just insulating the ceiling is not enough, I still hear occasional stomper. so the flooring now gets a 3mm padding as well on new renovations. Except the price used to be $60 for a roll of 200sqft now $120. Huge differences with just that insulation added.

 

[roblouvasz]

If the ceiling of the first floor is insulated, should it have be the type with the paper vapor barrier or not?

 

[yeldogt]

If the ceiling of the first floor is insulated, should it have be the type with the paper vapor barrier or not?

No need ..... just simple enfaced.