Insulating ceiling

[Ramper]

When we built our new home last year we insulated the wall of the garage but not the ceiling. We were planning on DIY later and it is now later. The ceiling is sheetrocked. We live in southern MN

A have a couple of question as I am not very knowledgable in this area:

Can I assume with the house being only 1 year old and the ceiling sheetrocked there is the proper venting in the ceiling? If not what should I be looking for?

Do I need to install insulation with facing and if so does the facing go towards the roof or towards the floor?

Is roll-out better than blown-in?

It is an L-shape with two cars deep on one side and two cars wide in the front. I do not know the exact dimension but wil update this when I measure.

The plan is to get a 60,000 or 75,000 BTU vented propane heater.


THANKS

 

[PaulR]

When we built our new home last year we insulated the wall of the garage but not the ceiling. We were planning on DIY later and it is now later. The ceiling is sheetrocked. We live in southern MN

A have a couple of question as I am not very knowledgable in this area:

Can I assume with the house being only 1 year old and the ceiling sheetrocked there is the proper venting in the ceiling? If not what should I be looking for?

Do I need to install insulation with facing and if so does the facing go towards the roof or towards the floor?

Is roll-out better than blown-in?

It is an L-shape with two cars deep on one side and two cars wide in the front. I do not know the exact dimension but wil update this when I measure.

The plan is to get a 60,000 or 75,000 BTU vented propane heater.


THANKS

I'm just a hack homeowner but I will take a stab at a few of these before the pro's arrive:

To my knowledge, ceilings aren't usually vented, roofs are. If your ceiling is sheetrocked you will want to use open face insulation. The paper face would have gone up against the drywall but there's no real proper way to get it in there now that the ceiling is up. Roll out versus blown in is a debate like Chevy versus Ford, it depends on who you ask. Roll out will stay nice and fluffy, not compact, but may leave gaps if not installed properly. Blown in will blanket everything with no gaps, but will compress and potentially lose its R value over time. If you are insulating your ceiling and the roof is up above you (as opposed to a bedroom or something), you might want to do some research on proper roof ventilation. You don't want to pack the ceiling tight up against the roof-line. Roofs need to breathe.

 

[trythis]

I always vote blown cellulose, its recycled, and doesn't itch, wont mold if it gets wet, bugs cant live in it, and I hate fiberglass.

 

[Falcon67]

Can I assume with the house being only 1 year old and the ceiling sheetrocked there is the proper venting in the ceiling? If not what should I be looking for?

No. We're buying a house built in 2001 and there are no roof top vents at all. Check your eves - make sure you have plenty of eve venting - and look on the roof for vents near the roof peak(s). When adding insulation, you will want to keep the area by the eves clear so air can travel up over the insulation. There are trays available to staple under the roof deck to make sure insulation doesn't block air movement.

Is roll-out better than blown-in?

For a small area (like our 22x22) roll is a bit easier, but blown in is much cheaper. Both work. With your seemingly large area, I'd rent a blower. If you go to sites like the Owens Corning AttiCat http://insulation.owenscorning.com/homeowners/insulation-products/atticat.aspx
they will tell you how much you need for the area and you can figure your cost from there. Locally, that particular blower is free with a $500 deposit and no minimum insulation buy at our McCoys.

 

[EdT]

After you price out all the stuff for doing it yourself, have a couple of quotes done. I did and I was surprised to find that I could have it done for the same money as doing it myself. Not a tough choice for me.

 

[jklingel]

Roll out versus blown in is a debate like Chevy versus Ford.... •• Not really. It is more a Chevy vs Porsche deal. FG batt insulation is THE WORST insulation material on the planet, esp when lain open like in a ceiling. There WILL be gaps, and it WILL have air passing through it. That will be minimal w/ cellulose. Too, FG looses its R value as the temp drops, ironically.

Blown in will blanket everything with no gaps, but will compress and potentially lose its R value over time. •• Better research that. Actually, the gravity-induced compression of loose blown cellulose has a minimal effect on its R value, and dense packed into a wall it will NOT settle. It should be dense packed at about 3.2 lb/cf, and blown loose it settles to about 2.5 lb/cf.

Roofs need to breathe. •• Roger that. So do walls.

pls see after the bullets above. later. j

 

[vtx531]

Is this even possible? I am in the same sitiation but I figured I can't insulate the ceiling because there is no vapor barrier and the ceiling is already up. I can't just blow in cellulose and call it good, can I?

 

[fastbuick]

Is this even possible? I am in the same sitiation but I figured I can't insulate the ceiling because there is no vapor barrier and the ceiling is already up. I can't just blow in cellulose and call it good, can I?

Looking for the same answer for my garage too. Fully drywalled with no insulation or vapor barrier in ceiling or exterior walls, it couldn't have been that much in savings when the house was built by the previous owner.

Been thinking about doing cellulose blown in the walls and ceiling, but then there is fiberglass?

 

[longboy515]

I don't think you need a vapor barrier for a garage, but I could be mistaken.

As for those with the ceiling already sheetrocked and wanting to insulate: do you have any rooms above the ceiling? or is it just open attic? If it's open attic, then I'd suggest doing blow-in with access via the attic access hole.

If you're ceiling is already sheetrocked and there's rooms/living space above the garage, you probably will have to cut out plug holes and do blown-in that way. I'm not sure how well it can flow sideways, but that might be the only option unless you want to redo the drywall.

 

[jklingel]

Obviously, the ideal way is to take the sheet rock down and re-apply it with the Airtight Drywall Approach, unless you are in zone 7 or 8 (very cold) where a true vapor barrier is suggested (or very hot, humid zones, sometimes, too). Even in Frb, zone 8, they only call for a perm rating of "one or less" (6 mil poly is 0.06), which is what the ADA is. The ADA lets the wall breathe in both directions. Once the 'rock is in, it is less than ideal, no matter what you do above. If the garage is used very little, hence very little water vapor, you'd likely be fine blowing in cellulose, I'D GUESS. Sheet rocking overhead is a PITA, but re-doing it is the safest way to go.

 

[Mario]

After you price out all the stuff for doing it yourself, have a couple of quotes done. I did and I was surprised to find that I could have it done for the same money as doing it myself. Not a tough choice for me.

X2

Having cellulose blown in my house roof was 50$ cheaper than installing fiberglass myself! (850$ vs 800$, a couple of years ago)

Make no mistake, I "love" handling fiberglass but hey, i'm cheap!

 

[Dominico]

What type of insulation would you normally have used if the ceiling wasn't finished? If the answer is rolled faced fiberglass batt's of insulation then why not use it if you can access the ceiling? First install vent baffles between each joist, then just roll it in-between each joist with the vapor barrier (paper) facing down,no need to staple. Make sure the insulation fits snug in each cavity. For the tough to reach areas just use a piece of furring strip to push the insulation in place. I did this on my 24x26 partially heated detached garage in two weekends and it was fairly easy to do.

Make sure you have proper eave and roof vents i.e. ridge or cans. If you need additional eave vents you can just cut the eave and install a vent (Lowe's & Home Depot sells them). They are very easy to install.

Everyone has a preference regarding the various types of insulation, however I will go with Fiberglass batt's any day. I have had, seen and heard of too many bad experiences with blown in insulation. Whatever you do you will see a noticeable improvement in the winter (warmer) and summer (cooler) seasons. It will be well worth the investment. Good luck!

 

[jklingel]

Everyone has a preference regarding the various types of insulation, however I will go with Fiberglass batt's any day. I have had, seen and heard of too many bad experiences with blown in insulation.

Too each his own, but the reality is that fiberglass batt insulation, esp where it is exposed, is PP insulation. (BTW: foil faced would be the worst to use, as it is cut to fit between studs and be fastened to "seal it". Ha ha. Friction fit would be better.) Any problems associated w/ blown-in cellulose are not the fault of the cellulose, but a fault with whoever did not manage their air properly, or allowed solid water in. Dry cellulose will sit for half an eternity, densely stopping convective currents, deterring bugs and rodents (if treated w/ borates), and providing great R values (both because of its ability to resist heat transfer and the fact that it fills gaps). FG is the worst insulation on the planet, P, EOS. No reputable building science organization says anything different. But, FG is cheap, and if it makes you feel good, then use it. It does help, no doubt about it; but, it ain't very good stuff.