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Ken Larson
12-20-2007, 07:55 AM
This is a first for me. In a brand new neighborhood all the homes were being constructed with expandable foam spray in the attics. No insulation between the ceiling joists and no visible attic ventilation at the back of the attic. Only ventilation was one gable vent.

I sure don't know of any waivers in the IRC that exempts this material from standard building practices. I still wrote them up for lack of insulation and ventilation.

Anyone seen this lately or know about this type of insulation method?

Scott Patterson
12-20-2007, 07:59 AM
That looks like an http://www.icynene.com/ installation. Good stuff if it is done properly. But what is pictured and with your description it does not sound like it was done properly.

By chance did you touch the foam? Was it soft and spongy or did it dent when you pushed on it?

With Icynene you do not insulate the attic floor. The attic is sealed off and should not have any ventilation from the outside. Any gas fired equipment must be provided with outside combustion air.

David Banks
12-20-2007, 08:55 AM
Adding to Scott.
BSD-149: Unvented Roof Assemblies for All Climates — (http://www.buildingscience.com/documents/digests/bsd-149-unvented-roof-assemblies-for-all-climates)

Jerry Peck
12-20-2007, 02:03 PM
Adding to Scott and David ...

From David's link:

Controls Rain Leakage – Closed-cell spray foam has negligible water permeability, minimal water absorption, and excellent adhesion allowing it to act as a secondary rainwater barrier to limit damage when primary roof assembly rainwater control membranes leak. Rainwater migration is severely limited due to the low water transmission and high adhesion (“waterproofing”) characteristics of the foam and damage is limited to the area immediately adjacent the hole in the primary rainwater control membrane. This tends to contain the damage, making it easier to identify the source and preventing it from spreading throughout the assembly and to interior finishes which can be costly to repair.

Yep. Just what some of us have been saying, but were told differently in the past ... at least now they are being honest about it.

"limit damage when primary roof assembly"

"Rainwater migration is severely limited"

"and damage is limited to the area immediately adjacent the hole"

Means that you will never see the leak from inside, and, of course, you will not see the leak outside, thus, one day, someone will be on the roof and the rotted roof decking will fall in ... because the leak has been "contained" right up against the roof sheathing.

"This tends to contain the damage, making it easier to identify the source and preventing it from spreading throughout the assembly and to interior finishes which can be costly to repair."

Huh? "making it easier to identify the source"? Ain't no way you are going to see the leak ... oh, I get it ... when the person steps through the roof sheathing it will be "easier to identify the source" by looking for the hole they stepped through - OH! I GET IT NOW! :p

Yeah, right.

That, however, seems to be the only major drawback to this stuff.

Scott,

"But what is pictured and with your description it does not sound like it was done properly."

What am I missing, other than Ken saying "Only ventilation was one gable vent.", which, if that part of the attic is also Icynene, there should not be any ventilation.

Scott Patterson
12-20-2007, 04:13 PM
Scott,

"But what is pictured and with your description it does not sound like it was done properly."

What am I missing, other than Ken saying "Only ventilation was one gable vent.", which, if that part of the attic is also Icynene, there should not be any ventilation.

The ventilation is one and the other would be the depth of the foam. It does not look like it has been sprayed deep enough, you can see the rafters and the collar ties transmitting though the foam. You should not be able to see them.

Jerry Peck
12-20-2007, 05:49 PM
It does not look like it has been sprayed deep enough, you can see the rafters and the collar ties transmitting though the foam. You should not be able to see them.

Wouldn't that depend on what R-value is required? If that is only an R-19 area, wouldn't that be sufficient?

Scott Patterson
12-20-2007, 07:11 PM
Wouldn't that depend on what R-value is required? If that is only an R-19 area, wouldn't that be sufficient?
I don't know. That would be logical, but then that stuff does not do real good on my logic meter! :D

Jim Luttrall
12-20-2007, 07:29 PM
R value is measured per inch just like anything else.
Sloppy work though.
I agree there should be NO ventilation, the conditioned envelope is moved from the attic floor to the roof just like a cathedral ceiling.
I still have problems with the exposed foam and covering it or not.
It is separated from the living area by the ceiling drywall, but does that meet the requirements of the IRC?
I have seen this in a few model homes and one retro-fit of an older home (which was a total mess), but never anything that has passed muster with a local AHJ.
I would be interested in the take on the applicable codes.

Jerry Peck
12-20-2007, 07:42 PM
I would be interested in the take on the applicable codes.

It is allowed.

From the 2006 IRC.


R806.4 Conditioned attic assemblies.Unvented conditioned attic assemblies (spaces between the ceiling joists of the top story and the roof rafters) are permitted under the following conditions:
- 1. No interior vapor retarders are installed on the ceiling side (attic floor) of the unvented attic assembly.
- 2. An air-impermeable insulation is applied in direct contact to the underside/interior of the structural roof deck. “Air-impermeable” shall be defined by ASTM E 283.
- - Exception:
- - - In Zones 2B and 3B, insulation is not required to be air impermeable.
- 3. In the warm humid locations as defined in Section N1101.2.1:
- - 3.1. For asphalt roofing shingles: A 1-perm (5.7 × 10 -11 kg/s ⋅ m2 ⋅ Pa) or less vapor retarder (determined using Procedure B of ASTM E 96) is placed to the exterior of the structural roof deck; that is, just above the roof structural sheathing.
- - 3.2. For wood shingles and shakes: a minimum continuous 1/4-inch (6 mm) vented air space separates the shingles/shakes and the roofing felt placed over the structural sheathing.
- 4. In Zones 3 through 8 as defined in Section N1101.2, sufficient insulation is installed to maintain the monthly average temperature of the condensing surface above 45°F (7°C). The condensing surface is defined as either the structural roof deck or the interior surface of an air-impermeable insulation applied in direct contact with the underside/interior of the structural roof deck. “Air-impermeable” is quantitatively defined by ASTM E 283. For calculation purposes, an interior temperature of 68°F (20°C) is assumed. The exterior temperature is assumed to be the monthly average outside temperature.

Matt Fellman
12-20-2007, 07:45 PM
That stuff looks like a total nightmare.... mainly because of what Jerry says.... until someone steps through the roof deck you'd never know you have a problem..... Do they even put attic access hatches in these houses? If so, why? It's like that old joke about just welding the hoods of the import cars shut.... you just throw them away when there's a problem.

Jerry Peck
12-20-2007, 07:48 PM
Do they even put attic access hatches in these houses? If so, why?

Does not compute ... one has nothing to do with the other??? :confused:

Jim Luttrall
12-20-2007, 10:14 PM
Jerry, Thanks for the 2006 IRC language, that is not in the 2003 that I have. Is the language fro R314.1.2 and R314.14.2.3 changed? Seems you brought it up in the past that foam had to be covered. When I read it, it seems a little ambiguous as to where the covering has to be. As I understand R314.2.3 Attics and crawlspaces, All foam plastics have to be protected from ignition, and the attic pictured would not fly. Any thoughts?

Matt Fellman
12-20-2007, 10:46 PM
Does not compute ... one has nothing to do with the other??? :confused:

I'm just joking around.... I can't imagine trying to do any work to anything in the attic after that gunk is sprayed all over the place.... So, what would be the point of getting in there.... hence the 'welded shut hood analogy' - I suppose if it needed this much explanation the joke was lost......

Eric Shuman
12-21-2007, 07:56 AM
Ken,

I guess this is starting to catch on in this area as I inspected a newly built home this week with the same stuff (probably the same installer as it is so uncommon). I was initially was alarmed when I was on the roof and did not observe any exhaust venting. It does require that no attic ventilation be present, presumably to keep the moisture out. I wrote it up as unconventional but allowed when properly installed and mentioned the lack of ventilation . I then of course stated that I was not qualified to properly evaluate the installation due to my unfamiliarity with the material and application.

This house also had a geothermal HVAC system, another uncommon thing in our area. Of course no one told me any of this when they scheduled the appointment even though they were aware. Would have been nice to do some research before I went.

I didn't like the fact that I could not see the framing connections of the roof structure. I listed the missing weather seal at the small constructed door between the garage attic space an the sealed attic area. I did write up the fact that they had encased the water heater b-vent in the stuff (see photo).

If anyone has any good install info on this stuff I would like to see it. The icycnene web site has some info.

Eric

brian schmitt
12-21-2007, 02:12 PM
one problem with this stuff is composition shingle manufacturer's may not honor their warranty with this methodology.i think elk brand may be one of the only companies to approve of this method. i guess heat build up damages some comp.

Jerry Peck
12-21-2007, 04:53 PM
I'm just joking around.... I can't imagine trying to do any work to anything in the attic after that gunk is sprayed all over the place....

Matt,

Actually, it is much easier to work on everything in the attic (of course, referring to what is below the insulation on the roof sheathing) - no insulation to get in the way and have to be moved around to work on whatever.

And, how often do you work on 'the roof sheathing' as compared to working on the wiring, ducts, recessed lights, etc.? Never?

Those attics are a breeze to inspect and you can see many things 'done wrong', with fire stopping, framing, you name it - simply because you can now see it out in the open.

Jerry Peck
12-21-2007, 05:17 PM
Is the language fro R314.1.2 and R314.14.2.3 changed?

Jim,

It has all changed.


SECTION R314
- FOAM PLASTIC
- - R314.1 General.
The provisions of this section shall govern the materials, design, application, construction and installation of foam plastic materials.
- - R314.2 Labeling and identification. Packages and containers of foam plastic insulation and foam plastic insulation components delivered to the job site shall bear the label of an approved agency showing the manufacturer’s name, the product listing, product identification and information sufficient to determine that the end use will comply with the requirements.
- - R314.3 Surface burning characteristics. Unless otherwise allowed in Section R314.5 or R314.6, all foam plastic or foam plastic cores used as a component in manufactured assemblies used in building construction shall have a flame spread index of not more than 75 and shall have a smoke-developed index of not more than 450 when tested in the maximum thickness of 4 inches (102 mm), provided the end use is approved in accordance with Section R314.6 using the thickness and density intended for use.
- - - Exception: Foam plastic insulation more than 4 inches thick shall have a maximum flame spread index of 75 and a smoke-developed index of 450 where tested at a minimum thickness of 4 inches, provided the end use is approved in accordance with Section R314.6 using the thickness and density intended for use.
- - R314.4 Thermal barrier. Unless otherwise allowed in Section R314.5 or Section R314.6, foam plastic shall be separated from the interior of a building by an approved thermal barrier of minimum 0.5 inch (12.7 mm) gypsum wallboard or an approved finish material equivalent to a thermal barrier material that will limit the average temperature rise of the unexposed surface to no more than 250°F (139°C) after 15 minutes of fire exposure complying with the ASTM E 119 standard time temperature curve. The thermal barrier shall be installed in such a manner that it will remain in place for 15 minutes based on NFPA 286 with the acceptance criteria of Section R315.4, FM 4880, UL 1040 or UL 1715.
- - R314.5 Specific requirements. The following requirements shall apply to these uses of foam plastic unless specifically approved in accordance with Section R314.6 or by other sections of the code or the requirements of Sections R314.2 through R314.4 have been met.
- - - R314.5.1 Masonry or concrete construction. The thermal barrier specified in Section R314.4 is not required in a masonry or concrete wall, floor or roof when the foam plastic insulation is separated from the interior of the building by a minimum 1-inch (25 mm) thickness of masonry or concrete.
- - - R314.5.2 Roofing.The thermal barrier specified in Section R314.4 is not required when the foam plastic in a roof assembly or under a roof covering is installed in accordance with the code and the manufacturer’s installation instructions and is separated from the interior of the building by tongue-and-groove wood planks or wood structural panel sheathing in accordance with Section R803, not less than 15/32 inch (11.9 mm) thick bonded with exterior glue and identified as Exposure 1, with edges supported by blocking or tongue-and-groove joints or an equivalent material. The smoke-developed index for roof applications shall not be limited.
- - - R314.5.3 Attics. The thermal barrier specified in Section 314.4 is not required where attic access is required by Section R807.1 and where the space is entered only for service of utilities and when the foam plastic insulation is protected against ignition using one of the following ignition barrier materials:
- - - - 1. 1.5-inch-thick (38 mm) mineral fiber insulation;
- - - - 2. 0.25-inch-thick (6.4 mm) wood structural panels;
- - - - 3. 0.375-inch (9.5 mm) particleboard;
- - - - 4. 0.25-inch (6.4 mm) hardboard;
- - - - 5. 0.375-inch (9.5 mm) gypsum board; or
- - - - 6. Corrosion-resistant steel having a base metal thickness of 0.016 inch (0.406 mm).
- - - - The above ignition barrier is not required where the foam plastic insulation has been tested in accordance with Section R314.6.
- - - R314.5.4 Crawl spaces. The thermal barrier specified in Section R314.4 is not required where crawlspace access is required by Section R408.3 and where entry is made only for service of utilities and the foam plastic insulation is protected against ignition using one of the following ignition barrier materials:
- - - - 1. 1.5-inch-thick (38 mm) mineral fiber insulation;
- - - - 2. 0.25-inch-thick (6.4 mm) wood structural panels;
- - - - 3. 0.375-inch (9.5 mm) particleboard;
- - - - 4. 0.25-inch (6.4 mm) hardboard;
- - - - 5. 0.375-inch (9.5 mm) gypsum board; or
- - - - 6. Corrosion-resistant steel having a base metal thickness of 0.016 inch (0.41 mm).
- - - - The above ignition barrier is not required where the foam plastic insulation has been tested in accordance with Section R314.6.
- - - R314.5.5 Foam-filled exterior doors. Foam-filled exterior doors are exempt from the requirements of Sections R314.3 and R314.4.
- - - R314.5.6 Foam-filled garage doors. Foam-filled garage doors in attached or detached garages are exempt from the requirements of Sections R314.3 and R314.4.
- - - R314.5.7 Foam backer board. The thermal barrier specified in Section R314.4 is not required where siding backer board foam plastic insulation has a maximum thickness of 0.5 inch (12.7 mm) and a potential heat of not more than 2000 Btu per square foot (22 720 kJ/m2) when tested in accordance with NFPA 259 provided that:
- - - - 1. The foam plastic insulation is separated from the interior of the building by not less than 2 inches (51 mm) of mineral fiber insulation or
- - - - 2. The foam plastic insulation is installed over existing exterior wall finish in conjunction with re-siding or
- - - - 3. The foam plastic insulation has been tested in accordance with Section R314.6.
- - - R314.5.8 Re-siding.
The thermal barrier specified in Section R314.4 is not required where the foam plastic insulation is installed over existing exterior wall finish in conjunction with re-siding provided the foam plastic has a maximum thickness of 0.5 inch (12.7 mm) and a potential heat of not more than 2000 Btu per square foot (22 720 kJ/m2) when tested in accordance with NFPA 259.
- - - R314.5.9 Interior trim. The thermal barrier specified in Section R314.4 is not required for exposed foam plastic interior trim, provided all of the following are met:
- - - - 1. The minimum density is 20 pounds per cubic foot (320 kg/m3).
- - - - 2. The maximum thickness of the trim is 0.5 inch (12.7 mm) and the maximum width is 8 inches (204 mm).
- - - - 3. The interior trim shall not constitute more than 10 percent of the aggregate wall and ceiling area of any room or space.
- - - - 4. The flame spread index does not exceed 75 when tested per ASTM E84. The smoke-developed index is not limited.
- - - R314.5.10 Interior finish. Foam plastics shall be permitted as interior finish where approved in accordance with R314.6. Foam plastics that are used as interior finish shall also meet the flame spread and smoke-developed requirements of Section R315.
- - - R314.5.11 Sill plates and headers. Foam plastic shall be permitted to be spray applied to a sill plate and header without the thermal barrier specified in Section R314.4 subject to all of the following:
- - - - 1. The maximum thickness of the foam plastic shall be 31/4 inches (83 mm).
- - - - 2. The density of the foam plastic shall be in the range of 1.5 to 2.0 pounds per cubic foot (24 to 32 kg/m3).
- - - - 3. The foam plastic shall have a flame spread index of 25 or less and an accompanying smoke developed index of 450 or less when tested in accordance with ASTM E 84.
- - - R314.5.12 Sheathing. Foam plastic insulation used as sheathing shall comply with Section R314.3 and Section R314.4. Where the foam plastic sheathing is exposed to the attic space at a gable or knee wall, the provisions of Section R314.5.3 shall apply.
- - R314.6 Specific approval. Foam plastic not meeting the requirements of Sections R314.3 through R314.5 shall be specifically approved on the basis of one of the following approved tests: NFPA 286 with the acceptance criteria of Section R315.4, FM 4880, UL 1040 or UL 1715, or fire tests related to actual end-use configurations. The specific approval shall be based on the actual end use configuration and shall be performed on the finished foam plastic assembly in the maximum thickness intended for use. Assemblies tested shall include seams, joints and other typical details used in the installation of the assembly and shall be tested in the manner intended for use.
- - R314.7 Termite damage. The use of foam plastics in areas of “very heavy” termite infestation probability shall be in accordance with Section R320.4.


Seems you brought it up in the past that foam had to be covered.

Only if the foam does not meet the fire spread and smoke developed ratings, and most of that stuff does (I think).


When I read it, it seems a little ambiguous as to where the covering has to be.

Does not state where the gypsum board or equivalent needs to be, only that it need to separate (be between) the foam and the living space.

As I understand R314.2.3 Attics and crawlspaces, All foam plastics have to be protected from ignition, and the attic pictured would not fly. Any thoughts?[/quote]

Refer to bold and underlined text above - start at "Attics" and "Crawl spaces". It refers to other sections which refer to other sections which refer to ... :D

Jim Luttrall
12-21-2007, 05:24 PM
Thanks for the post Jerry, definitely changes in the wording.
Jim

Jerry Peck
12-21-2007, 05:37 PM
I did write up the fact that they had encased the water heater b-vent in the stuff (see photo).

Yeah, they tend to miss leaving a 1 inch air space around that, and, to be honest, the first couple of attics I saw with that stuff, I missed catching it too. Wasn't until about my third house in the same sub division where I went 'OOPS! I forgot to write that up on the first two. Oh, well, I'll just include a note on this report referencing *like installations in other homes in the same subdivision need to be corrected also, including blah-blah and blah-blah*.' That worked and the builder had his insulation contractor go back and correct those first two, and go down the street in front of me correcting the rest (under the presumption that I would eventually inspect the other houses in there, and I eventually did inspect them).

Looks like a flexible aluminum vent duct connected to a foil duct at the end on the right. If it is only an 'air duct' (such as from a bath fan), don't know of a prohibition against using that foil duct up there, but the connection between the two different types needs to be done properly. And both need to be properly supported (that flexible one is also bent).

The vertical flexible duct on the left in the photo needs to be supported every 6 feet vertically.

Lots of loose 'everything' in that photo. Pipes, wiring, etc. need to not only be 'supported', but 'secured' as well, at proper intervals. What type of piping is 'not secured or supported' in that black insulation?

Eric Shuman
12-22-2007, 08:09 AM
Jerry,

Yeah, I included those issues im my report. The insulated pipe appeared to be the copper water piping that connects the geothermal system to the gas water heater. The gas had not been connected to the water heater at the time of inspection but the Geothermal system was doing a good job of supplying hot water.

Concerning the b-vent, the builder said something to the effect of the insulation is fire/combustion resistant. I told him that even if true I thought that was irrelevant because among other things, the b-vent has to have the 1 inch air space for heat dissimination.

This new home was in a rural area. You know how it is, it seems that the ones built in rural areas always have more issues since there is rarely a code official inspecting the construction. For the most part though, this house was in good order.

Eric

Jim Luttrall
12-22-2007, 09:02 AM
dissimination

maybe dissipation?

mike huntzinger
12-22-2007, 04:42 PM
I did a simular house where there are no attic vents, and because of the sealed nature of the attic, some of the A/C was filtered into the space

Jerry Peck
12-22-2007, 08:59 PM
I did a simular house where there are no attic vents, and because of the sealed nature of the attic, some of the A/C was filtered into the space

Mike,

Sometimes those attic are referred to as 'conditioned' attics and other times they are referred to as 'semi-conditioned' attics (to me, the latter is more correct as I have yet to see an attic which supply air going into it to "condition" the attic.

If the return air is being drawn in through the above ceiling space via an open (but filtered) return at the air handler and a return air opening in the ceiling somewhere ... that makes that above ceiling space (the entire attic) *a "plenum". That would create all kinds of "plenum" related issues. Man would that create problems.

Eric Shuman
12-25-2007, 09:35 AM
maybe dissipation?


Yup, dissipation - that's what I meant.

Eric

Matthew Skowron
12-27-2007, 06:49 AM
Matt Fellman

"Do they even put attic access hatches in these houses?"


The attics in these houses are conditioned for the most part we have alot of these houses in Kerrville texas. This is unusaly tight const. and has its own set of problems.

The main gripe i hear is keeping the HVAC running long enuff to 1.) replace the air in the house and 2.) to pull moisture out of the house. One fix they used was to introduce outside air into the system via a 4in PVC pipe into the return air side and had a attic inline filter system.(This was an ENG. fix and i dont understand why this worked, but it did)

to answer your question directly

Yes, if there is equipment in the attic they do and most do for access for storage :)

Jerry Peck
12-27-2007, 05:43 PM
Matt Fellman asked: "Do they even put attic access hatches in these houses?"

Matthew Skowron replied: "Yes, if there is equipment in the attic they do and most do for access for storage"

Actually, attic access is required for firefighters when the headroom clearance is at least 30 inches in the attic. That 30 inch minimum headroom shall also be provided at some point above the access opening (I really don't like that wording, but that is what it has evolved to). This is, of course, where there is no mechanical equipment or water heater in the attic.