Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Roofing/Siding

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 02-27-2009, 01:44 PM   #1
Newbie
 
Join Date: Feb 2009
Posts: 7
Rewards Points: 0
Share |
Default

Insulation Question(s)


Hey all,

I've a question I could not find answered in prevous posts..

I'm in North Carolina (eastern) I've an unfinished Attic that had blowin throughout, and i plan to create a media room (with help).

The current insulation (blow in) needs to be compacted down to the rafters (2x6's) to be able to add a subfloor, this reduce the R value and made the less resiliant to sound. So I plan on placing R30 down over the blow in to make up the insulation as well as help increase density and assist reducing sound between floors.

- Question is this ok to do rather than remove the blown in?
- Does a Vapor barrier need to be inplace between two floors that are heated/cooled - couldn't find anything to say that is does.
- Behind Knee walls the insulation WILL NEED a vapor barrier facing inwards to the warm room is that correct?

Thanks for you time.

POLO

POLOMiNT is offline   Reply With Quote
Old 02-27-2009, 02:13 PM   #2
Remodeling Contractor
 
Join Date: Dec 2008
Location: Sandy Hook, CT
Posts: 3,590
Rewards Points: 0
Default

Insulation Question(s)


making the insulation denser will make it less effective and less sound deadening. No vapor barrier between floors. Vapor barrier is not needed a vapor retarder is. Use kraft faced insulation facing inside on the knee walls.

Bob Mariani is offline   Reply With Quote
Old 02-27-2009, 02:20 PM   #3
Newbie
 
Join Date: Feb 2009
Posts: 7
Rewards Points: 0
Default

Insulation Question(s)


Thanks bob for answering.

I have to reduce the density to be able to add the subfloor to the joists, so i guess with your answer is remove the blowing and replace with fiberglass batts to botain the R-Value required.

I've also read that fiberglass batts are better than blowin as a sound suppressant due to the tighter density which goes inline with sound suppressing materials this isn't to say it's the soul soundprooing i'll be using but will help.

But the main question can I reinforce the Blow in insulation with Fiberglass over the top and then obviously subflooring etc..

cheers.

POLO

Last edited by POLOMiNT; 02-27-2009 at 02:25 PM.
POLOMiNT is offline   Reply With Quote
Old 02-27-2009, 02:30 PM   #4
Remodeling Contractor
 
Join Date: Dec 2008
Location: Sandy Hook, CT
Posts: 3,590
Rewards Points: 0
Default

Insulation Question(s)


you could, just do not pack it tightly. Also look into sound attenuation batts instead.
Bob Mariani is offline   Reply With Quote
Old 02-27-2009, 02:32 PM   #5
Member
 
Join Date: Dec 2007
Location: Baltimore, MD
Posts: 1,802
Rewards Points: 0
Default

Insulation Question(s)


Quote:
Originally Posted by Bob Mariani View Post
making the insulation denser will make it less effective and less sound deadening. No vapor barrier between floors. Vapor barrier is not needed a vapor retarder is. Use kraft faced insulation facing inside on the knee walls.
Why would you put a vapor retarder between conditioned floors? While I agree compacting the insulation will hurt the thermal efficiency, I don't think it will hut the sound attenuation of it. Sound blocking material is usually very dense. The mass of the material is what helps absorb the sound enerygy.

Last edited by jerryh3; 02-27-2009 at 02:34 PM.
jerryh3 is offline   Reply With Quote
Old 02-27-2009, 02:35 PM   #6
Remodeling Contractor
 
Join Date: Dec 2008
Location: Sandy Hook, CT
Posts: 3,590
Rewards Points: 0
Default

Insulation Question(s)


I would not.. I said nothing in the floor only the knee walls. Maybe it was a run-on sentence. Sorry for the confusion. Answer was in general that code specifies a vapor retarder, not vapor barrier thus the faced insulation on the outside walls faced to the warm side.
Bob Mariani is offline   Reply With Quote
Old 02-27-2009, 02:35 PM   #7
Member
 
Join Date: Dec 2007
Location: Baltimore, MD
Posts: 1,802
Rewards Points: 0
Default

Insulation Question(s)


Are you saying you are going to use the 2x6's as the floor of the new room?
jerryh3 is offline   Reply With Quote
Old 02-27-2009, 02:37 PM   #8
Member
 
Join Date: Dec 2007
Location: Baltimore, MD
Posts: 1,802
Rewards Points: 0
Default

Insulation Question(s)


Quote:
Originally Posted by Bob Mariani View Post
I would not.. I said nothing in the floor only the knee walls. Maybe it was a run-on sentence. Sorry for the confusion. Answer was in general that code specifies a vapor retarder, not vapor barrier thus the faced insulation on the outside walls faced to the warm side.
Gotcha.
jerryh3 is offline   Reply With Quote
Old 02-27-2009, 02:38 PM   #9
Newbie
 
Join Date: Feb 2009
Posts: 7
Rewards Points: 0
Default

Insulation Question(s)


Thank you Jerry, Thank you Bob,

You both have clear this up for me, just wanted to ensure that it was ok. but behind the knee wall I did think a vapor retarder would be required so thank you both on you replies.

I look forward to posting more questions in the future.

POLO

Last edited by POLOMiNT; 02-27-2009 at 02:54 PM.
POLOMiNT is offline   Reply With Quote
Old 02-27-2009, 02:53 PM   #10
Newbie
 
Join Date: Feb 2009
Posts: 7
Rewards Points: 0
Default

Insulation Question(s)


Quote:
Originally Posted by jerryh3 View Post
Are you saying you are going to use the 2x6's as the floor of the new room?
It's a little more complex than that, these 2 x 6 run across (8-11ft) into 2 x10 on the lower load bearing walls.

So yes but they not as you would be thinking the only supports of the floors, i've had a survey done and they are load bearing for what i'm planning and should be fine .

does that make sense?

Last edited by POLOMiNT; 02-27-2009 at 03:36 PM.
POLOMiNT is offline   Reply With Quote
Old 02-27-2009, 03:03 PM   #11
Newbie
 
Join Date: Feb 2009
Posts: 2
Rewards Points: 0
Default

Insulation Question(s)


Hey Polo, new to this fourm but been in Construction for 30 years and I have never liked that blown in stuff, so if it was mine I would remove it and make a pillow or bed or something with it (about all its good for).. what is your main purpose for this? Sound proff or heat/cooling retention? Be careful with the insulation between the knee walls/ceilings and roof sheeting to not hinder your air flow out the ridge vents and soffits..(**BIG PROBLEMS THERE BUDDY**)!
StereoJoe is offline   Reply With Quote
Old 02-27-2009, 03:14 PM   #12
Newbie
 
Join Date: Feb 2009
Posts: 7
Rewards Points: 0
Default

Insulation Question(s)


Hey Joe,

Thanks man, I'll take any advise, I’m learning and willing to understand as many points of views as i can so thank you..

the main purpose is turn the Attic into a living space but mainly as a media/entertainment area. I've an engineer coming out next week mainly because of a Gable Dormer that will need reinforcing as it has no header where the laminated beams come together at the ridge.

Because of the raised ceiling below the floor is set at three levels, I’ve checked and there is plenty of room for the regulation 7.5ft (9.5ft actually) living space and total space will be about 8-900ft overall.

First plan to do is insulations between floors at a minimal cost, and then have a framer bring the lower parts of the floor up to the second level maxing out the overall end part of the floor plan, then add sub flooring then a 2x6 knee wall (for extra insulation and increase the space between the front and rear sheet rock.

Obviously there alot more involved but that the general approach I have in mind

Oh and yeah i know exactly what you mean about the soffits, i do plant to add 1 ridge vent/baffle with insulation in to the soffit to reduce the sound coming in from outside but to still maintain the air flow to the ridge vent. Where the angle in the roof is I need the baffels again to transfer the moisture/air from dead space behind the knee walls to the ridge vent as well.. btu good point one i had to read over and over again..

POLO

Last edited by POLOMiNT; 02-27-2009 at 03:21 PM.
POLOMiNT is offline   Reply With Quote
Old 02-27-2009, 03:49 PM   #13
Newbie
 
Join Date: Feb 2009
Posts: 2
Rewards Points: 0
Default

Insulation Question(s)


I think you should be fine with the 2X6's for the floor, POLO. Just as long as you are not planning on having some 300 lb pole dancer with 50 pals jumping and raising hell and blasting lound tunes!
StereoJoe is offline   Reply With Quote
Old 02-27-2009, 03:51 PM   #14
Newbie
 
Join Date: Feb 2009
Posts: 7
Rewards Points: 0
Default

Insulation Question(s)


lmao... i bloody well hope not as well..

thanks Joe.

POLO
POLOMiNT is offline   Reply With Quote
Old 02-27-2009, 03:52 PM   #15
Member
 
Join Date: Dec 2007
Location: Baltimore, MD
Posts: 1,802
Rewards Points: 0
Default

Insulation Question(s)


Quote:
Originally Posted by StereoJoe View Post
I think you should be fine with the 2X6's for the floor, POLO. Just as long as you are not planning on having some 300 lb pole dancer with 50 pals jumping and raising hell and blasting lound tunes!
You make that sound like a bad thing...

jerryh3 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Cape Cod Style House Attic/Crawl Space Insulation Help Danielg Insulation 24 05-21-2012 08:20 AM
Basement Insulation Questions? BobR General DIY Discussions 1 09-30-2008 09:25 PM
Finishing the basement- tons of insulation questions QueenL Building & Construction 2 04-01-2008 01:25 PM
Some Basement Insulation Questions atilla137 Building & Construction 6 10-16-2006 11:57 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.