Attic Insulation Help Needed-What type, etc

HandyFrank

Need some guidance on insulating my attic. Here are the details:
-Currently there is no insulation
-The house is built with 2X4 Joists that sit on sill beams at the front and back of the house
-I have recessed lighting cans installed in 2nd floor bedrooms, the cans are rated IC to contact insulation
-I live in the NorthEast where it gets cold in the winter, and hot in the summer
-The house is old (1920's)so there isn't really any insulation so I don't expect a leak proof house, just want to get lots of insulation into the attic to help keep the 2nd floor warmer, and keep the heat from escaping easily.


What type of insulation should I use?
Fiberglass Type
If I go with the rolls/batts, I've researched that I definitely should use a faced insulation and put the faced side downward leaving just the the fiberglass facing upward. I read that you could even install sheets of foam insulation over the rolls/bats in the joists to help even further but I've never seen that done.

Blown In
I've considered the blown stuff but even though that seems to be more efficient it seems like more of a mess in the long run?
I have 14 recessed light cans installed on the 2nd floor and those are protruding well above tte 2X4 Joists. Lowes rents the machine for $20 a day so that isn't bad, I've just never done this nor has anyone I talked too.

Rating?
Seems like most people say R-30 but I also read on an energy stat type site that R-38 to R-60 could be used if I go with Fiberglass type.

What To Do?
Was thinking of just buying fiberglass rolls in Either R-30 or R-38 or R-60 and putting it in the joist bays and calling it a day.
OR
I have access to unfaced R-30 so I was thinking I could put down faced insulation first between the joists, and then put the R-30 unfaced running perpendicular to the joists on top of that for 2 solid layers of insulation.
OR
Consider blowing it in.

Any tips appreciated!

Octopus

Sounds to me anything is going to help. Lots of void air space with batts. I say blow it in. With blown in, R 38 is about 10 inches deep. Please be sure your cans are IC rated. If not, can covers will be required prior to ANY insulation being added to the attic

HandyFrank

Thanks for the insight. Yes, the Cans are IC rated, made sure they were prior to the installation since I knew I would be insulating eventually.

The house is old so anything is better than nothing I figure, and even with an attic insulated perfectly the rest of the house won't be, so I'm looking to do a good job, but I'm not shooting for a green award

I've never done the blowing, seems messy? I know that cutting fiberglass isn't fun either, but with a respirator it isn't too bad. Any specifics on the blow in process will be helpful, but I'm still leaning towards the pink rolls I think.

If I plan to go with just 1 roll in each joist bay, think R-30 faced or R-38 will be decent?

mrgins

Blown in. Even tho you have an older house which allows moisture out in many places (I'm sure!), the cellulose will allow moisture to pass thru. Before you insulate, it's a good time to plug any penetration thru the ceiling to prevent excessive heat loss (pipe and wire penetrations).

operagost

Since your house was built in the 1920s, it may still have knob-and-tube electrical wiring. Are you sure that none exists where you intend to install insulation? K&T needs airflow, so a complete weatherization requires an upgrade.

HandyFrank

Any down sides to blown in other than that it is messy? Does it settle with time and then requires more to be added later? Does it use the same type of materials or do they loose quality over time?


Was all BX wiring added after the original build, but has been upgraded to 14-2 and 12-2 romex now so that isn't an issue.

Any other feedback on insulation is welcome.

mrgins

It will settle slightly and needs someone with experience to put it in correctly.

TTony

What about spray foam insulation. Open cell in the attic. I have an older home in Galveston and intend to used closed cell sprayed under the floor ( pier and beam).

jklingel

Whatever you do, do impeccable air sealing before you install any insulation. Blown in cellulose is easy to diy, cheap, bug/rodent/fire retardant, and good R.

M3 Pete

Yep. Buy yourself a case of expanding foam and go to town. Seal the tops of all the walls to the top plate (both interior and exterior walls), all pipe penetrations, any HVAC ducts where they enter the walls or ceiling, electric boxes and wiring holes, etc. You want to stop all airflow between the walls/ceiling and the attic.

Also seal those recessed lights if they are not air-tight. You can buy air tight trim, but it really needs a gasket, which is not included.
http://www.amazon.com/Halo-30WATH-6-...3977668&sr=8-6

http://www.homedepot.com/buy/lightin...kit-51301.html

Alternatively, you can seal the cans from above using foil flue tape on all the openings
http://www.amazon.com/3M-2113NA-High.../dp/B00004Z4DS
or hi-temp foil duct tape like Nashua 324A (good to 325F). You can seal the bottom of the cans to the ceiling with expanding foam, since that area does not get that hot (because the baffle is between the light and the can, the bulb is usually well above the bottom of the can, and heat rises).

Remember to keep insulation of any kind away from furnace or water heater chimneys.

And while you are in the attic, you should seal up and insulate all HVAC ducts if you have not already. For sealing, use either HVAC mastic or FOIL tape (not cloth "duct" tape)
http://rcdmastics.com/
http://www.findtape.com/category47/a...foil-tape.aspx

Here is a quick primer on mastic sealing
http://rcdmastics.com/images/stories...aling_peae.pdf