Yet another insulation thread! Promise this one is different!

[RustnGrease]

I'll try and make this as easy and painless as possible. So we're buying a house very soon, and alas in december, not the summer/fall as we would've liked. Either way the house has what i would call a 3 season attic, no heat plumbed. Also only some insulation in certain areas between the 2nd floor and attic. Currently fiberglass batts. There's a floor pretty much through the entire attic with some access points. And 0 insulation on the attic ceiling/roof.

My question is, what's my best route to insulate between the 2nd floor ceiling and attic floor? 2x6's for joists IIRC. No vapor barrier currently present either. With how it currently is i can see money going right out the door for heating the 2nd floor living space.

I could potentially remove some of the floorboards and install fiberglass batts, but that would be a pain, also considering doing DIY blown in insulation. Would hate to remove all of the floorboards. I know it won't be the R-49/R-60 thats recommended for around here but something has to be better than nothing.

Also to raise the entire floor to have enough depth of insulation for R-49/60 is somewhat out of the question.

 

[Off-Street Parking]

What are your eventual plans for the attic?

Yes, there is heat transfer through the second floor ceiling, but that heat isn't completely lost... It's heating your attic.

If you insulate below the attic floor, your un-heated attic is going to be a lot colder in the winter. If you want the attic to be more moderate temperatures year-round, you might consider insulating the underside of the roof instead.

 

[RustnGrease]

We eventually plan on finishing off part of the attic to make into a master bedroom, probably wont be for 5-10 years or so. At this point we're looking to let the attic be cold. As it has 0 insulation in the wall or roof. Also to insulate the roof it's going to take some ingenuity to insulate the attic/roof due to construction.

 

[DC73]

A good choice for your situation is to create an un-vented attic by using spray foam on the bottom side of the roof deck.

DC

 

[Denwood]

+1 on spray foam the attic ceiling. With older construction, balloon framing etc, doing a decent air seal on the 2nd floor ceiling will be very difficult. Spray foam the attic ceiling, making sure you seal up the top of exterior walls, and you're done. If you do add insulation to the 2nd floor ceiling, but still have a lot of air leakage to the attic, the colder space may result in frost problems, and spring leaks.

 

[RustnGrease]

Thanks guys, its obviously an older home, 1930's construction, originally a barn converted into a house back in the 60's i believe. I would consider it timber framed, with stud walls added to make rooms. Also the attic is completely open, except for the beam framing. We'd like to keep at least some of the original framing visible for asthetics(?) from the attic ceiling to where the roof angles is approx 6 feet then the peak is approx 12' up from that. So it's huge, approx 30x60. That's alot of dead air space, especially without having heat plumbed up there as of yet. I should've mentioned this previously SORRY!