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Robert Alexander
10-17-2008, 08:07 AM
This is first time I have seen batt insulation installed in crawlspace that did NOT have a vapor barrier (paper or foil face) at all. Usually I expect to see this and it is installed toward heated side of home (of course).

Is this Ok?

Jerry Peck
10-17-2008, 08:35 AM
From the 2006 IRC.

- SECTION R318
- - MOISTURE VAPOR RETARDERS

- - - R318.1 Moisture control.

In all framed walls, floors and roof/ceilings comprising elements of the building thermal envelope, a vapor retarder shall be installed on the warm-in-winter side of the insulation.
- - - - Exceptions:
- - - - - 1. In construction where moisture or freezing will not damage the materials.
- - - - - 2. Where the framed cavity or space is ventilated to allow moisture to escape.
- - - - - 3. In counties identified as in climate zones 1 through 4 in Table N1101.2.

I suspect that each of the exceptions above apply to the area you are referring to.

First, you are in Climate Zone 3, which means exception 3 applies.

Second, exceptions 1. and 2. look like they will also apply.

Gunnar Alquist
10-17-2008, 12:31 PM
Unfaced insulation is the standard in my area.

Robert Alexander
10-17-2008, 01:14 PM
Perfect. Thanks Jerry.

John Arnold
10-17-2008, 01:16 PM
Gunnar - The apostrophe troll? First of all, you haven't told us the answer to "What is the circumference of a moose". Or is that a Zen koan, like "what is the sound of one hand clapping"?
Does the apostrophe troll pop up when people write "it's" inappropriately? As in, "I seen this moose the other day, and it's circumference was unmeasurable"?

Sorry, I have nothing useful to add to the actual subject of this thread.

Terry Beck
10-18-2008, 08:32 AM
Robert,

Aside from Jerry Peck's authoritative code answer (thank you), my experience leads me to recommend against faced insulation in vented crawlspaces. You also have to understand that I live in a cold climate with moderate levels of seasonal humidity.

Specifically for the insulation installed at the rim joists. I have inspected countless number of crawlspaces that may look fine initially, but I have learned to always pull the fiberglass batting away from the rim joists for an extra look. Many, many homes will have at least some discoloration from condensation trapped against the rim joists by insulation with vapor barrier, and sometimes the beginning (or worst) of wood rot. Even with unfaced fiberglass batting, it still appears, but to a lesser extent. I saw one house with a 4-yr old addition where the rim joists were completely rotted out (there were muliple problems there though).

I don't find as many problems with insulation installed on the underside of the sub floor, but still do find it sometimes. Plus, about 99% of the people that do install fiberglass batting on the underside of the sub floor, like to install it upside down with the vapor barrier facing the crawlspace, not the floor.

I have begun leaning toward recommending some sort of rigid foam board sealed with caulking at the rim moist, or spray on foam insulation, to prevent the intrusion of moisture ladder air against the joists. But even there, the jury is out. These effects of course will vary based on local climate.

Gunnar Alquist
10-18-2008, 10:05 AM
Gunnar - The apostrophe troll? First of all, you haven't told us the answer to "What is the circumference of a moose". Or is that a Zen koan, like "what is the sound of one hand clapping"?
Does the apostrophe troll pop up when people write "it's" inappropriately? As in, "I seen this moose the other day, and it's circumference was unmeasurable"?

Sorry, I have nothing useful to add to the actual subject of this thread.

John,

Someday I will have a good answer for the moose circumference.

Yes, I have started whining about improper use of the apostrophe and might start pointing out improper word usage again. I think Billy Stephens labeled me "the apostrophe troll" in the "cool room" thread, and I gleefully adopted it.

Things like their/there and your/you're drive me nuts.

I know, I should probably get a life, watch some football and mellow.

Jerry Peck
10-18-2008, 10:16 AM
Things like their/there and your/you're drive me nuts.


I don't know, Gunnar, those things, along with hear/here, site/cite/sight, and all the other drive me nuts too (as well as to/too/two). One would think that HIs would have, and us, a spell checker, being as proper grammar in their reports is typically indicative of their professionalism (or at least taken as representing their professionalism by their readers).

I'm not an English Major, and in fact hated English so much that I found away around taking it seriously in high school, but still, we should know how to write, being as writing is so much of what we do (and add ad/add and do/due to that list of things).

:)

Billy Stephens
10-18-2008, 04:32 PM
.
I think Billy Stephens labeled me "the apostrophe troll"
.
.
Somebody Must Have Been messing around on my System ( Again ! ) :D
*better get on the phone with tech support.
.

Gunnar Alquist
10-19-2008, 02:31 PM
JP,

Thanks for that. I agree with your comments regarding professionalism as well. I realize that someone's knowledge of construction and the various systems is not necessarily related to his/her ability to write, but I do feel that knowledge of the proper word (to/too/two), grammar and spelling is important as it does reflect on that individual's care and dedication to her/his profession as well as the profession as a whole.

Billy Stephens
10-19-2008, 02:55 PM
JP,

Thanks for that. I agree with your comments regarding professionalism as well. I realize that someone's knowledge of construction and the various systems is not necessarily related to his/her ability to write, but I do feel that knowledge of the proper word (to/too/two), grammar and spelling is important as it does reflect on that individual's care and dedication to her/his profession as well as the profession as a whole.
.
New Avatar for your new signature. :)
.

Brandon Chew
10-20-2008, 05:27 AM
I don't know, Gunnar, those things, along with hear/here, site/cite/sight, and all the other drive me nuts too (as well as to/too/two). One would think that HIs would have, and us, a spell checker, being as proper grammar in their reports is typically indicative of their professionalism (or at least taken as representing their professionalism by their readers).

I'm not an English Major, and in fact hated English so much that I found away around taking it seriously in high school, but still, we should know how to write, being as writing is so much of what we do (and add ad/add and do/due to that list of things).

(my bold) ;)


JP,

Thanks for that. I agree with your comments regarding professionalism as well. I realize that someone's knowledge of construction and the various systems is not necessarily related to his/her ability to write, but I do feel that knowledge of the proper word (to/too/two), grammar and spelling is important as it does reflect on that individual's care and dedication to her/his profession as well as the profession as a whole.


Eye halve a spelling checker
It came with my pea sea
It plainly marques for my revue
Miss steaks eye kin knot sea.

Eye strike a key and type a word
And weight four it to say
Weather eye am wrong oar write
It shows me strait a weigh.

As soon as a mist ache is maid
It nose bee fore two long
And eye can put the error rite
It's rare lea ever wrong.

Eye have run this poem threw it
Eye am shore your pleased two no
It's letter perfect awl the weigh
My checker tolled me sew.

Jim Zborowski
10-20-2008, 01:28 PM
maybe we should just type in the psycho abreviations that teens do in their I-M's...................4 = for, waddup = whats up, kind of like that.

Gunnar Alquist
10-20-2008, 02:15 PM
Brandon

Gud won.

Billy Stephens
10-20-2008, 05:07 PM
.
...............4 = for, waddup = whats up, kind of like that.
.
Or even less typing . :D
.

Mike Schulz
10-26-2008, 05:21 PM
Gunnar, Hola, no ablo english. No hablo mucho español. So please correct me when I am wrong. Gracias por su ayuda.

Gunnar Alquist
10-26-2008, 05:27 PM
Gunnar, Hola, no ablo english. No hablo mucho español. So please correct me when I am wrong. Gracias por su ayuda.


'Choo becha!

bruce m graham III
10-27-2008, 04:19 AM
My father inlaw was a big stickler for grammer and such, I would always get with "irregardless" . You could just see the fire in his eyes sometimes.:)
I miss that old boy

Jerry Peck
10-27-2008, 07:10 AM
I would always get with "irregardless".

"irregardless" is like a double negative.

"ain't got no", which actually means "you got some".

"irregardless" means without without regard, or, with regard. :D

irregardless

One entry found.
Main Entry: ir·re·gard·less
Pronunciation: \ˌir-i-ˈgärd-ləs\
Function: adverb
Etymology: probably blend of irrespective and regardless
Date: circa 1912
nonstandard : regardless (http://www.merriam-webster.com/dictionary/regardless)
usage Irregardless originated in dialectal American speech in the early 20th century. Its fairly widespread use in speech called it to the attention of usage commentators as early as 1927. The most frequently repeated remark about it is that “there is no such word.” There is such a word, however. It is still used primarily in speech, although it can be found from time to time in edited prose. Its reputation has not risen over the years, and it is still a long way from general acceptance. Use regardless instead.

Gunnar Alquist
10-27-2008, 03:28 PM
My father inlaw was a big stickler for grammer and such, I would always get with "irregardless" . You could just see the fire in his eyes sometimes.:) I miss that old boy

grammar, not grammer. :cool:

Jerry McCarthy
10-27-2008, 05:04 PM
FWIW "Fowler's Modern English Usage" is my go-to book when I'm not sure if I'm using our language correctly.

Rainer Michelis
01-07-2010, 12:11 PM
Hi,
I am new in this forum and hopefully, I am not boring you all with the "same" question. However, so far I have not found an answer to my problem. I am living in NJ and we bought a house a few weeks ago (finished basement, 1st floor (hardwood), partially 2nd floor (carpet)). After taking out the carpet we realized that the cats had ruinded the subfloor and we will replace a big part of this as well. Because I like to be energy efficient, I was thinking to use the open floor to put in some insulation. On both floors there are 2x10s - 15" apart. There are articles that say don't put insulation into the foor and others that say do it.
The reason is simple: I want the living and family room (and the floor) to be warm and the bedrooms colder. The questions I have are:
- can I use unfaced R-30 (home depot is haveing a good sell ;-) and put it between the 2x10s?
- do I really need a vapor barrier? The temp. difference between the basement, 1st and 2nd floor shouldn't be that much to have condensation?
- JM R-30 is also used for sound proofing- any experience?

It's amazing but you ask 5 people and you get 6 different opinions. All I am looking for is a warmer floor and some soundproofing.
Thank you so much for your help!
Rainer

Gunnar Alquist
01-07-2010, 12:41 PM
Hi,
I am new in this forum and hopefully, I am not boring you all with the "same" question. However, so far I have not found an answer to my problem. I am living in NJ and we bought a house a few weeks ago (finished basement, 1st floor (hardwood), partially 2nd floor (carpet)). After taking out the carpet we realized that the cats had ruinded the subfloor and we will replace a big part of this as well. Because I like to be energy efficient, I was thinking to use the open floor to put in some insulation. On both floors there are 2x10s - 15" apart. There are articles that say don't put insulation into the foor and others that say do it.
The reason is simple: I want the living and family room (and the floor) to be warm and the bedrooms colder. The questions I have are:
- can I use unfaced R-30 (home depot is haveing a good sell ;-) and put it between the 2x10s?
- do I really need a vapor barrier? The temp. difference between the basement, 1st and 2nd floor shouldn't be that much to have condensation?
- JM R-30 is also used for sound proofing- any experience?

It's amazing but you ask 5 people and you get 6 different opinions. All I am looking for is a warmer floor and some soundproofing.
Thank you so much for your help!
Rainer

It's funny, I actually read the entire thread and when I got to the last post, wondered why this individual was posting a question about insulation when it was clearly about grammar & spelling. Had to go back to the beginning to remind myself about the original post.

Rainer,

You will get different opinions here as well. It depends on where you are putting the insulation. If I read your post correctly, it sounds as though you want to put insulation in the floor between the first and second floor. Unfaced insulation should be fine there. However, if you are putting insulation between heated and unheated areas, such as under the first floor, it should be a faced insulation with the vapor barrier toward the living space.

However, the benefit of insulating between the first and second floor will be minimal. There won't really be any significant energy savings because it is all within the building envelope and still will be heated. Yes, fiberglass insulation is used for sound insulation and there might be some benefit there. But, sound isolation is a specialty in itself and typically requires hanging the drywall from special channels to help minimize the sound transfer through the joists.

If you are looking for sound insulation between floors, there might be other sites that would be more helpful.

Jim Luttrall
01-07-2010, 12:57 PM
Hi,
I am new in this forum and hopefully, I am not boring you all with the "same" question. However, so far I have not found an answer to my problem. I am living in NJ and we bought a house a few weeks ago (finished basement, 1st floor (hardwood), partially 2nd floor (carpet)). After taking out the carpet we realized that the cats had ruinded the subfloor and we will replace a big part of this as well. Because I like to be energy efficient, I was thinking to use the open floor to put in some insulation. On both floors there are 2x10s - 15" apart. There are articles that say don't put insulation into the foor and others that say do it.
The reason is simple: I want the living and family room (and the floor) to be warm and the bedrooms colder. The questions I have are:
- can I use unfaced R-30 (home depot is haveing a good sell ;-) and put it between the 2x10s?
- do I really need a vapor barrier? The temp. difference between the basement, 1st and 2nd floor shouldn't be that much to have condensation?
- JM R-30 is also used for sound proofing- any experience?

It's amazing but you ask 5 people and you get 6 different opinions. All I am looking for is a warmer floor and some soundproofing.
Thank you so much for your help!
Rainer

Insulation goes on at the thermal barrier between the inside and outside of the house or between conditioned and unconditioned areas of the house.
If you really wanted different room temperatures and have no openings (like open stairways) between floors then go for it. Un-faced would be the correct choice between the 2nd and 3rd floors since there would be little thermal or moisture drive between interior rooms and you would want it to dry to both sides.

Scott Patterson
01-07-2010, 01:10 PM
I don't see any problem with installing the unfaced insulation. It is done all the time when homes are built and the owners want to reduce the amount of noise that is heard in the rooms. I doubt that you will notice any major difference in the room temperatures just by using batt insulation.

Mike Schulz
01-07-2010, 02:06 PM
I recommend using Insulation designed for noise reduction. Higher end homes will install in bathroom walls adjacent to living room, family room and god forbid the kitchen.

chris mcintyre
01-07-2010, 06:20 PM
Insulating bathroom and laundry room walls has become standard for me, all the feedback I get says it makes a big difference.

The last custom home I built the owners wanted the master bedroom walls insulated. They claimed it was so the TV in the family room didn't interrupt their sleep ;).

Rainer Michelis
01-13-2010, 05:19 PM
Wow ... that went fast. I am amazed how fast I got the responses and best of all, I think they are pretty usable and confirm what I was thinking.
Regarding the vapor barrier - I have checked underneath the subflooring and ... voila, some areas have insulation without any vapor barrier.
Once again thank you all for the fast and competent help!
Rainer

Mike Schulz
01-14-2010, 09:30 AM
Rainer,

In out area I believe if the soil is covered with plastic vapor barrier you can use un-faced Insulation. May be a better solution to cover the ground then replace the Insulation.

gary gramling
01-17-2010, 08:56 AM
Jerry,
I found a way or method to get past those English requirements; but, I was away at the time.

CHARLIE VAN FLEET
01-19-2010, 10:29 AM
hey all
have been following this thread

yesterday came across a new 16 foot kitchen addition-with a crawl access--could not see anything except vapor barrier on insulation hanging out of press board nailed to joists. remember this is 16 feet long and some 25 feet wide. i couldn't even see any center support or what kind of beams were installed {see photo}

so question is--contractor said insulation is double sided vapor retarder--is this right and should it be covered with this wood--city inspector finaled it

what do you think

charlie

Mike Schulz
01-19-2010, 11:35 AM
Picture?

CHARLIE VAN FLEET
01-19-2010, 11:41 AM
senior moment sorry

John Kogel
01-19-2010, 08:43 PM
hey all
have been following this thread

yesterday came across a new 16 foot kitchen addition-with a crawl access--could not see anything except vapor barrier on insulation hanging out of press board nailed to joists. remember this is 16 feet long and some 25 feet wide. i couldn't even see any center support or what kind of beams were installed {see photo}

so question is--contractor said insulation is double sided vapor retarder--is this right and should it be covered with this wood--city inspector finaled it

what do you think

charlieThat would be all wrong where I live. The insulation needs to breath. Moist air or moisture can get trapped on top of the press board. But maybe it won't. :)

I've seen basements or crawls where they had stapled poly under the insulation and everything looked bone dry. I still call it wrong, suggest they monitor for moisture problems.

Maybe they had a rat problem and solved it that way?

The lack of a beam under that floor is a concern, all right. Any spring in the floor?