Directon of faced insulation over bathroom?

Reply

  #1  
Old 02-09-19, 04:05 PM
Member
Thread Starter
Join Date: Nov 2013
Posts: 101
Directon of faced insulation over bathroom?

Hello - I need to install insulation in the attic over a full bath that has an exterior wall. It's my understanding I should use faced insulation for a vapor barrior since there is no previous insulation laid down. Does the "faced" side go down toward the ceiling/house or up facing the roof? I heard it varies based on your region but I am in the Northeast where we do get cold winters but it also can get fairly hot in the summer.
 
Sponsored Links
  #2  
Old 02-09-19, 04:09 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 21,358
Faced side to the interior.
 
  #3  
Old 02-09-19, 07:42 PM
Member
Thread Starter
Join Date: Nov 2013
Posts: 101
If I need more R-value, can I stack unfaced rolled insulation or blown in insulation on top of the base layer of the faced insulation? Does it matter what type?
 
  #4  
Old 02-09-19, 07:45 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 21,358
Yes you can. And no it doesnt. If you do more batts put them perpendicular.
 
  #5  
Old 02-09-19, 09:29 PM
Member
Thread Starter
Join Date: Nov 2013
Posts: 101
Thanks for your help. Eventually I want to better insulation the rest of the attic. I have a lot of areas with blown-in insulation already there but it's not enough. Would you still recommend laying unfaced insulation over it perpendicular even though it could probably stack on top of what's already there?
 
  #6  
Old 02-09-19, 10:13 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 21,358
The whole point of laying it perpendicular is so that there are no gaps. If it fits between the joists you have a 1 1/2" gap everywhere. If you lay it on top of the joists you can push it tight. If you have blow in, I would forget the vapor barrier and blow more in.
 
  #7  
Old 02-10-19, 03:01 AM
Group Moderator
Join Date: Oct 2004
Location: WI/MN
Posts: 18,892
I'm with X in that I would add more blown in rather than batts.
 
  #8  
Old 02-10-19, 10:48 AM
Member
Thread Starter
Join Date: Nov 2013
Posts: 101
That makes sense, for any other area (aside from above this bathroom) - I could just have more blown in.

Unfortunately above this bathroom I had only installed unfaced insulation (all the blown in got lost when the ceiling got replaced). I get moisture from the shower on the ceiling all the time when it's cold so that's why I am planning to install R-38 Faced Insulation Batts above that area. Hopefully that will take care of the moisture issue.
 
  #9  
Old 02-10-19, 10:52 AM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 21,358
A vapor barrier won't have anything to do with whether or not the ceiling gets wet. It gets wet because it's a cold surface and the dewpoint is highest at the ceiling.

If you don't have an exhaust fan yet now is the time.
 
  #10  
Old 02-10-19, 04:58 PM
Member
Thread Starter
Join Date: Nov 2013
Posts: 101
Unfortunately I way over-calculated insulation in a past home project so I have a lot of faced R-38 batts sitting around to use.

Here is a picture of the bathroom in question where I get moisture on the ceiling when it gets cold. It does have an exhaust fan that seems to run just fine. I removed the R-13 insulation that was there and replaced it with faced R-38 as pictured. I still don't know if this will fix the issue though but I think the insulation that was there previously wasn't enough (plus it was unfaced). I made sure to use ventilation channels as shown in the 2nd picture.

Since I have so much of these R-38 batts, I would still like to lay them perpendicular over the blown insulation in other areas of the attic. I know you said it would be best to just blow in more insulation but since I have these R-38 batts I might as well use them. It's been easy to remove the paper from them so that shouldn't be an issue. Assuming I install ventilation channels can I just lay down the batts perpendicular as shown in my 3rd picture? The 4th picture is a reference of what my current situation is in regard to the blown in insulation.

Thanks again for all the quick replies. I sure need the help, obviously!

Name:  f1.jpg
Views: 16
Size:  21.3 KB

Name:  f2.jpg
Views: 15
Size:  31.0 KB

Name:  f3.jpg
Views: 15
Size:  24.1 KB

Name:  f4.jpg
Views: 16
Size:  49.3 KB
 

Last edited by PJmax; 02-11-19 at 09:44 AM. Reason: resized pictures
  #11  
Old 02-10-19, 05:13 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 21,358
Yes, as long as you don't block the soffit ventilation. You should also lay a lot of insulation over your bath fan. That cold metal could drip water in the winter otherwise.
 
  #12  
Old 02-11-19, 07:02 AM
Member
Join Date: Jan 2008
Location: usa
Posts: 143
Is that the bath fan vent stack in the attic? Looks like it just dumps into the attic. Or, does it terminate outside?
 
  #13  
Old 02-11-19, 05:52 PM
Member
Thread Starter
Join Date: Nov 2013
Posts: 101
Thanks for the tip, I will insulation over the fan. Yes it is connected to a stack vent(?) in the roof. I did find that the flexible duct is leaking though so maybe it got a hole in it somehow. I will have to replace it.

I did have another question on the soffit ventilation. I am trying to install plastic vent chutes but I am finding I can't reach far enough down to staple them for the length of the chute. Even doing an army crawl, it's physically impossible to reach far enough down to staple the bottom.

Is it OK to just have 3-4 staples at the top to hold it in place or will I run into issues later? I figure the insulation batts will even further hold them in place. I wanted to ask before installing all of these though as I have atleast 100 to do. See pictures for detail on what I am talking about. Thanks again.
 
Attached Images    
  #14  
Old 02-11-19, 06:06 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 21,358
Yes, stuffing insulation snugly underneath them will hold them up.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes