CC Sprayfoam Roof Deck Inspector Wants More Insulation - 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!

Like Tree1Likes
  • 1 Post By Bud9051
Reply
 
Thread Tools
Display Modes
Old 11-14-2018, 08:39 PM   #1
Dco
Newbie
 
Join Date: Oct 2018
Location: Ontario, Canada
Posts: 7
Rewards Points: 4
Default

CC Sprayfoam Roof Deck inspector wants more insulation


Hello DIYers


Hopefully someone can chime in here.


Location: Toronto, Canada, Climate Zone 6


Project: knock down wall between living room and kitchen and raise ceiling


House :a bungalow

I have raised the ceiling and opened the space between living room and kitchen. Permits are approved.


We have insulated the roof deck with 2lbs closed cell spray foam (R32 Code) and planned to install the ceiling drywall after inspection.

Problem: Inspector wants to see insulation (blown in) in the ceiling joists where the "new attic" is (see photo). Specifically he wanted to a vapour barrier and additional insulation however I am told there is no point by 2 insulation experts that adding extra insulation may cause issues with moisture. His arguement was that the space between ceiling and roof deck is too "large", its not. One can barely crawl around there if you wanted to. Secondly, the spray foam is closed cell and should act as a airtight vapour barrier itself

The inspector doesn't seem to confident but he isnt budging on his decisions. I am ok with doing what is asked but insulation experts are countering and saying it might do more harm than good.


Any information or direction on how to educate the inspector, I am siding with the experts here.

sources; https://cufca.ca/docs/CUFCA_SPF_GUID...erox_Press.pdf


https://greenappleinsulation.com/rem...on-spray-foam/






I've done a little research and removal of floor/ceiling insulation is recommended when adding in closed cell sprayfoam.


Ive done a little drawing to help illustrate the issue. There maybe 2ft of height space if that, the Red area is what he wants to see blown in.....


Thank you!
Attached Thumbnails
CC Sprayfoam Roof Deck inspector wants more insulation-insulation-q.jpg  
Dco is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 11-14-2018, 08:53 PM   #2
Member
 
Join Date: Oct 2008
Location: Ontario
Posts: 5,061
Rewards Points: 9,040
Default

Re: CC Sprayfoam Roof Deck inspector wants more insulation


How could that cause a moisture issue?
SPS-1 is online now   Reply With Quote
Sponsored Links
Advertisement
 
Old 11-14-2018, 09:53 PM   #3
Member
 
Join Date: Nov 2015
Location: Maine
Posts: 8,842
Rewards Points: 7,812
Default

Re: CC Sprayfoam Roof Deck inspector wants more insulation


I reviewed your links, basically familiar with them anyway and they contain all of the information you need. But getting your local inspector to accept them and omit the need for added ceiling insulation will depend upon him. Has he read those articles?

I have a couple of questions. R-32 seems low, but none of my business. I'm in zone 6 to your east and on my side of the boarder and our minimum ceiling insulation is R-49.
Also, didn't see an ignition barrier shown. Drywall or a intumescent paint are sometimes required.
@SPS-1 a winter issue for moisture would be diffusion or air leakage transporting moisture into that space with no way for it to get out. And with insulation above and below the resulting temp in there could drop below the dew point. The space actually needs access to some heat and some eir exchange, aka conditioning.

Bud
__________________
I volunteer my help and opinions, but you are responsible for what YOU choose to do with that information.
Bud9051 is online now   Reply With Quote
Sponsored Links
Advertisement
 
Old 11-14-2018, 09:54 PM   #4
Dco
Newbie
 
Join Date: Oct 2018
Location: Ontario, Canada
Posts: 7
Rewards Points: 4
Default

Re: CC Sprayfoam Roof Deck inspector wants more insulation


yes my research tells me the same! Again I am not an expert, anymore info (ammo) would be greatly appreciate to educate this inspector.


I can only find small snippets from installer websites. He's being very difficult.
Dco is offline   Reply With Quote
Old 11-14-2018, 11:19 PM   #5
Dco
Newbie
 
Join Date: Oct 2018
Location: Ontario, Canada
Posts: 7
Rewards Points: 4
Default


Thanks for the reply, r31 is the min code here . 5/8 Sheetrock will be applied On ceiling joists. Never heard about itumscent paint being needed. Maybe you have tougher codes.

I’m installing pot lights and since drywall isn’t much of a vapour barrier

The inspector also called for a poly vapour barrier in additon to the blown in insulation ? Meaning the I would have two vapour barriers, the cc spray foam and the poly.

P.s I am not adding any HVAC to this space ...not adding in insulation to the ceiling allow enough air exchange ? I’m adding in these flat led IC rated pot lights and I anticipate air leakage
Dco is offline   Reply With Quote
Old 11-15-2018, 12:32 AM   #6
Member
 
Join Date: Nov 2015
Location: Maine
Posts: 8,842
Rewards Points: 7,812
Default

Re: CC Sprayfoam Roof Deck inspector wants more insulation


Check out Joseph Lstiburek who Hails from Toronto so he is definitely familiar with code requirements on your side of the border and I suspect some of his articles or others from GBA (Green Building Advisors) or BSC (Building Science Corporation) will be sufficient to sway your inspector. If you do not find what you want you can ask them directly through related links. Choose some key words and add GBA to see more of what they have written.

"I
ntumescent" paint would be an alternative to the drywall if local authority would accept it albeit expensive. 5/8" drywall would be fine without the special paint.

Leakage around pot lights would not be sufficient to qualify as air flow. IMO, you should plan on an active fan flow between that space and the living space below. Obviously, that conflicts with adding blow-in insulation to the ceiling.

His suggestion to add a plastic vapor barrier illustrates he has not be attending the education seminars. I usually meet my local code officer at every event I attend. Note adding that would be in addition to the vapor retarding characteristics of the paint you use. One VB is often questionable, 2 is bad, 3 is definitely a problem. BTW, VBs have fallen out of favor and been replaced by air sealing. Diffusion moves so little moisture.

Bud
firehawkmph likes this.
__________________
I volunteer my help and opinions, but you are responsible for what YOU choose to do with that information.
Bud9051 is online now   Reply With Quote
Old 11-15-2018, 09:33 AM   #7
Dco
Newbie
 
Join Date: Oct 2018
Location: Ontario, Canada
Posts: 7
Rewards Points: 4
Default


Thanks again Bud

Much appreciate you sharing your knowledge
Dco is offline   Reply With Quote
Old 11-29-2018, 12:47 AM   #8
Dco
Newbie
 
Join Date: Oct 2018
Location: Ontario, Canada
Posts: 7
Rewards Points: 4
Default


Hi all

Just want to Bump, still talking this one over with the city.

I am stuck, city inspector wants more insulation and with a vapour barrier because of the airspace in between. ... I don’t get it . The space is not even big enough to crawl through.

they want me add venting to the roof, cutting through my spray foam....

Or add additional HVAC system

I am at a loss....

Everywhere I look I see the same application I have done .unvented attic space with close cell spray foam... am I missing something.
Dco is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply


Thread Tools
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
Roof repair versus reroof and which contractor to believe? miamicuse Roofing/Siding 42 01-12-2015 10:05 AM
Is it safe to build a roof over my Hawai'i deck? ModelM2HB Building & Construction 11 07-03-2012 07:22 PM
Install a deck on top of a EPDM flat roof. -Pjackso Roofing/Siding 16 08-02-2010 04:35 PM
Blown Insulation - Flat roof AndrewF Roofing/Siding 1 12-31-2009 07:41 PM
Insulation on top of old roof deck??? ubie42 General DIY Discussions 6 01-05-2009 07:22 PM




Top of Page | View New Posts