Best Option To Insulate A Contemporary Home/low Pitch Roof - Insulation - DIY Chatroom Home Improvement Forum
Advertisement


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Insulation

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

Reply
 
Thread Tools Search this Thread
Display Modes
Old 11-12-2013, 10:01 PM   #1
wkd
Member
 
Join Date: May 2013
Location: NJ
Posts: 59
Rewards Points: 106
Default

best option to insulate a contemporary home/low pitch roof


Hi,

I'm looking for some input on how to best go about insulating the roof of my contemporary house. The top floor (where all the bedrooms are) gets unbearably hot in the summer ... it was not uncommon to see temps of 94-96 degrees.

The house has a low pitch roof (2/12) and no attic so the ceilings of the bedrooms just radiate heat and the AC is useless. If I'm lucky, I can get the temp down to the mid 80s.

The house has a lot of faults (thanks previous %*#[email protected]% owner!) that were quickly addressed to get the house sold and I now I get to fix them all.

The ceilings in the bedrooms are coming down to address lighting issues and install wiring for fans and I am hoping to better insulate to help deal with this ridiculous heat.

I'd really like to have someone come in and spray foam but honestly, given everything I've had to fix in the past two years, that is probably out of the budget.

I came across this article: http://www.thisoldhouse.com/toh/arti...5422-6,00.html

"Before switching to spray foam insulation, Tom used to use polyisocyanurate panels that way—he would build a 2x4 wall, insulate between the studs with batting (paper face removed), then cover the whole thing with foil-faced panels and seal them with foil tape before putting up wall board. The combined R-value of the batts and board on the 2x4 wall was more than batts alone on a 2x6 wall, and he would gain a little extra space in the room."

Can this concept be done for the ceiling?

Or what about using this stuff between the insulation and sheetrock ?

http://www.homedepot.com/p/Reach-Bar...2#.UoL0WXCfixk

Searching the forum, I can across a post that mentions 'froth paks' ... is this spray foam a DIYer can use? How would I address venting ? I'm not even sure I could use this as the roof extends down to the 'mid' level (the house is a split level ... walk in at ground level and the stairs going up/down are at the other side of that level) and the ceiling in the mid level (most likely with batt insulation) is not coming down as the central a/c manages to cool that area quickly.

I dont know if I'm explaining it correctly. Basically the mid and upper level share the roof and I'd only be taking down the ceilings in the bedrooms and possibly the hallway but that would mean that the common roof would be half batt insulation (mid level) and half spray foam (bedrooms and hallway) ... would that work or would that just lead to massive problems down the road?

Thanks for reading!
wkd is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 11-14-2013, 08:55 PM   #2
Registered User
 
Join Date: Mar 2009
Posts: 11,730
Rewards Points: 526
Default


The foil radiant won't work without a 3/4 (min.) air space. Better to use that space for fibrous cavity fill and add the PIC to the rafters, first said that here about 4 years ago, lol, when I first joined. With the air space ventilation behind it, faced or unfaced batt wouldn't matter, moisture will not diffuse through a foil-facing.

You could also piece-meal some XPS in the cavities of the sloped ceilings---- at least at the edges where any fiber would touch the air baffles for conduction and be lower R-value than the wall because of the low clearance at exterior wall-line there; http://www.buildingscience.com/docum...n-roof-venting
Just leave 2" clear for ventilation due to low slope, steeper pitch needs only 1".

SPF requires thick enough for your Zone to prevent condensation--- see map in my previous link.

Want to lower the heat coming through the roof, increase the insulation and change the color of roofing to white next re-roof, if not already.
ADA the drywall includes air ceiling the recessed lights; http://www.buildingscience.com/docum...wall-approach/

Gary
__________________
If any ads are present below my answer or words underlined/colored, I do not condone/support/use the product or services listed/linked to, they are there without my consent.
17,000 dryer fires a year, when did you last clean the inside of the dryer near motor or the exhaust ducting?
Gary in WA is offline   Reply With Quote
The Following User Says Thank You to Gary in WA For This Useful Post:
wkd (11-18-2013)
Sponsored Links
Advertisement
 
Old 11-18-2013, 08:20 PM   #3
wkd
Member
 
Join Date: May 2013
Location: NJ
Posts: 59
Rewards Points: 106
Default


Gary - thanks for replying.

So to make sure - you're saying after putting in baffles, put PIC across the rafters (or in between and then drywall directly to the studs?) and then fill the space between the baffle and PIC with fibrous cavity fill? Is that the insulation you blow in ? If the PIC goes across the rafters, would I have to then screw in furring strips then drywall? Not sure how thick the PIC is but Im assuming this would lower my ceiling by at least 2 inches ? If thats the case, it seems like it would be an issue with the windows as the ceiling would come down right to the top of the windows, and I would be able to re-install the (top) trim.

Ideally, I'd like to replace the roof but its only about 3 years old, replaced by the previous owner.
wkd is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 11-18-2013, 11:41 PM   #4
Registered User
 
Join Date: Mar 2009
Posts: 11,730
Rewards Points: 526
Default


This will work also, long as it's vented; http://www.google.com/url?sa=t&rct=j...foKjI2qFXXOoLg

Gary
__________________
If any ads are present below my answer or words underlined/colored, I do not condone/support/use the product or services listed/linked to, they are there without my consent.
17,000 dryer fires a year, when did you last clean the inside of the dryer near motor or the exhaust ducting?
Gary in WA is offline   Reply With Quote
The Following User Says Thank You to Gary in WA For This Useful Post:
wkd (11-19-2013)
Sponsored Links
Advertisement
 
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
Old Roof - Trying to ventilate and insulate Ilinizas Building & Construction 8 08-23-2012 12:24 AM
1930's low pitch roof audiohere Roofing/Siding 15 07-15-2012 07:33 PM
Need opinion on this roof profenx Roofing/Siding 14 10-12-2010 12:56 AM
Changing Pitch over roof. tying into house rafters? EnlightMent Roofing/Siding 3 03-27-2007 12:16 AM
Flat roof - Rolled? - leaks Advice? JJ2001 Roofing/Siding 4 11-19-2006 06:17 AM




Top of Page | View New Posts