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Basement Ceiling Insulation - up or down?

apollosmith

07:23PM | 11/18/02

Basement Ceiling Insulation - up or down?

I have searched all over the place for an answer to this - please help! I am finishing my semi-heated basement and adding a home theater. I am adding R-19 insulation between floor (basement ceiling) joists for sound proofing. For heating and sound-proofing, what direction should the insulation facing go - up or down? Is R-19 the best option? What else would help sound proof the room (beside 5/8" drywall)? Would it make economical sense to insulate the entire basement ceiling - some sites say 'yes' others say 'no'. Thanks!

stpat

03:16PM | 11/19/02

Member Since: 11/16/02
23 lifetime posts

First off, let the joist heigth determine what size (thickness) insulation you use. Chances are you have 6" joists, so R19 is correct. Never cram insulation into an opening (if you took a 2x4 wall which calls for R11, and crammed R19 (6") in the space, you would actually have R13).

As far as a facing goes, insulation that supports a sound rating is not faced at all! It is actually a full size center. If your joists are 16" on center, you would think you need a15" batt, which is what normal insulation is. But sound insulation is a true 16" wide. Don't worry about it falling out, friction will hold it up long enough to put drywall up.

You can also take things a step father by using sound board, and RC1 channel as well. I can explain those to you if you wish.

I would suggest insulating the entire basement if you are going to improve the whole basement.

The above material will not be found in your local "Big Box"(you will confuse the heck out of them), you must go to an actual building material dealer. The company I sell for has been selling these items for offices, condos, ect. for years now.

By the way 5/8" will give you a better rating than 1/2".

stpat

03:24PM | 11/19/02

Member Since: 11/16/02
23 lifetime posts

by the way, you cannot sound-proof your basement....you can create a sound deadening system

WallyV

07:30AM | 11/20/02

Member Since: 01/16/01
71 lifetime posts

Just in case you don't know, if you plan to light the basement with recessed cans be sure to follow instructions when insulating around them. NON-IC cans cannot have insulation contact and IC cans will tolerate contact with insulation.

Chris A

12:00PM | 11/21/02

Member Since: 11/20/02
1 lifetime posts

Oh NO! .... My builder, who has today been finishing boarding my basement ceiling, is putting recess lights in. At last minute today I gave him rockwool to put between the beams, which he did prior to boadring.I have not a clue what kind of cans he is using, but if they do turn out to be Non IC, what effect will this have??? (Worried)

By the way, forgive my ignorance here, but what is IC? Will my builder know what I am talking about???

LDoyle

02:15PM | 11/21/02

Member Since: 06/03/01
324 lifetime posts

The 'IC' designation basically means 'In Contact'. They are rated to have insulation in direct contact with the cans. Non-IC usually require insulation to be a minimum of 6 inches away from the can. These can be a fire hazard if insulation is too close and could affect your insurance coverage in the event of a fire.

stpat

04:59PM | 11/21/02

Member Since: 11/16/02
23 lifetime posts

Sounds like everything is under control....Just curious, where did you get the term "rockwool", that is a nickname that is really no longer used.