Fox re: attic

[Deleted]

OK FoxInFiji, I'm getting up in the attic today and starting to insulate our ceilings.  DH got up there yesterday and talked out a way we think we will approach re-finishing the space, and I wanted to run it by you.  Here's the space again for reference: pandce.proboards.com/thread/114633/spirit-januarys-challenge-bad-pips

After I get all of the plywood ripped up and ceilings insulated, we are planning to re-lay the plywood in this finished area and I'll probably paint the plywood floor.  All the ceilings behind the drywall walls are currently insulated, so we're good to go there.  We do have really thick old joists, so there's room for a decently deep layer of insulation under the plywood I think. 

As far as the roof, we're ripping out all the drywall against the roof and removing the insulation to allow the roof to breathe properly.  We're then thinking about running 1x spacers perpendicular to the rafters and then putting tongue and groove boards up as a ceiling, much like our guesthouse: images2.snapfish.com/232323232%7Ffp54363%3Enu%3D325%3B%3E6%3B2%3E874%3EWSNRCG%3D3848%3A49%3A4832%3Cnu0mrj

We're thinking the 1x spacers would allow the roof to breathe even more under the wood, and the tongue and groove itself would breathe well. 

My suggestion was to just leave the ceiling as rafters and I could just paint it to make it more cheerful, but DH hated that.

We'd be leaving all the drywall walls up, since I really like the existing closet and drawers for storage. 

What are the possible problems with that plan?  I'm most worried about unconditioned moist air being pulled in onto the existing drywall with all the new venting and breathing.  Perhaps I could remove the drywall and replace it with plywood, which I could paint?  I don't know.  I want to do this the easiest way possible but not have it mold or look absolutely terrible, since I do go up there semi-regularly for sorting, filing, exchanging seasonal items, etc.  I don't hate going up there right now.

[FoxInFiji]

Hmm personally I would buy the plastic or foam baffles like these. A video here as well.

Then put the batt insulation and then the drywall or bead board nailed onto the rafters. It will take a up a little more space but you don't really gain a lot of space between the rafters on the ceiling anyway right? If your worried about moisture you can put some painters caulk between the seams of the beadboard (with drywall just mud as usual) before you paint. You would use a faced batt so there is somewhat of a vapor barrier there. It's not a heated or cooled by your furnace so yes it does have a possibility of getting wide temperature and humidity swings. But that shouldn't wreck the drywall.

[Deleted]

  I'm not sure I get it.  It seems like if we went in favor of insulating the roof rather than our living area ceilings, it would be more like conditioned space, since we've be leaking all our heat into the attic.  Anyway, I already started insulating our ceilings (the floor of the attic).  I guess we'll decide about the roof/rafters when we get there.  Two layers of insulation (floor and ceiling of attic) can't be a bad thing I guess.  DH is totally against insulating the roof, believing the air won't circulate well on the bays that don't have venting paths, even with the baffles.  THe roofer cut in 6 soffit vents to vent to the ridge.

ETA: thank you for reading and responding to my neverending roof saga.

[FoxInFiji]

Oh so you want it to be unconditioned. OK well then yeah you can just add drywall or beadboard anywhere as long as you leave a gap of some sort for airflow. The 1x's or 2x's should work fine for that. A bigger airflow gap doesn't hurt anything if you have the space.

I was just treating is as a hobbled together slightly more temperature regulated space. Treating it as another floor basically. You can insulate between floors. It's usually done more for sound than anything but it also helps keep the air that is supplied to the space in. This room wouldn't have that though and since it's just kind of hobbled together (not perfectly sealed and vapor barriered) the insulation in the floor helps keep your house's heat and cooling inside not in the attic space. I live in the cold north though so I insulate everything possible when it's open and accessible.

Does that make sense? You can decide to put more insulation there or not it's up to you. Just make sure to maintain the venting space.

[Deleted]

THat help, thanks! We read over the links you sent, and it seemed like leaving the attic outside the insulation envelope seemed better, but I wasn't sure if that meant I couldn't have any finishing up there. We don't have extremes, but since we do have to get that insulation out of the roof, I want something between us and the sky to keep my heat in. We may not get freezing cold, but it does get nippy!