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Lbear
Veteran Member
Posts:2740
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| 22 Mar 2012 02:39 AM |
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Posted By robinnc on 21 Mar 2012 11:17 PM
Texas....what type of roof are on those houses with a sealed attic? I had my shingles replaced about 12 yrs ago and the roofer(several I talked to) said I did not have enough venting is why I needed to replace the shingles(they were in bad shape). They told me if I had a sealed attic(I asked about this) the shingles would probably only last half of the years expected from them.
I read the same about roof materials. I believe what happens is that the roof is subjected to higher heat loads vs. a vented attic/roof. Asphalt shingles are the "least expensive" form of roofing material. Tile roofing would last a lot longer but they are heavy. The best option is a standing seam metal roof. While upfront costs are more, those roofs will last 50+ years. They are lightweight but extremely strong. |
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TexasICF
Advanced Member
Posts:622
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| 22 Mar 2012 06:06 AM |
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Robinnc, if you had this discussion 12 years ago you were way ahead of the rest of the county. Many builders around here using foam still see this as innovative. However, I've heard of the problem you mention but have never experienced it or seen it firsthand. My house is concrete tile.
If you are interested I will email you a design I came up with a couple of years ago that adds ventilation and a radiant barrier to a sealed foamed roof. Regards. |
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Lbear
Veteran Member
Posts:2740
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| 22 Mar 2012 05:17 PM |
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Out here in Phoenix homes mostly have vented attics but even so, homes with asphalt shingle roofs have about 1/2 the life of an asphalt shingle roof in a more moderate climate. The sun/heat destroys the shingles very quickly. A better option is tile/concrete roofs, which account for about 60% of the roofs in Phoenix.
The reason WHY builders use asphalt shingle roofs is that they are inexpensive and fast to install but must be replaced in 10 years out here in Phoenix. A concrete tile roof will get 20 years out here before the underlayment needs to be replaced. The tile can still be reused but the waterproof underlayment is what breaks down. Lastly, a standing seam metal roof, which is more common further north, but they will last at least 50+ years.
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robinnc
Advanced Member
Posts:586
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| 22 Mar 2012 07:12 PM |
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I'd like to see that design Texas. |
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TexasICF
Advanced Member
Posts:622
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| 22 Mar 2012 09:10 PM |
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Send me a PM and I'll send it to you.
Regards |
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Dana1
Senior Member
Posts:6991
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| 23 Mar 2012 06:35 PM |
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Posted By Lbear on 22 Mar 2012 05:17 PM
Out here in Phoenix homes mostly have vented attics but even so, homes with asphalt shingle roofs have about 1/2 the life of an asphalt shingle roof in a more moderate climate. The sun/heat destroys the shingles very quickly. A better option is tile/concrete roofs, which account for about 60% of the roofs in Phoenix.
The reason WHY builders use asphalt shingle roofs is that they are inexpensive and fast to install but must be replaced in 10 years out here in Phoenix. A concrete tile roof will get 20 years out here before the underlayment needs to be replaced. The tile can still be reused but the waterproof underlayment is what breaks down. Lastly, a standing seam metal roof, which is more common further north, but they will last at least 50+ years.
True-dat! The notion that venting is a solution for extending shingle life has been largely debunked- sounds great in theory, but doesn't measure up so well when monitored carefully in side-by-side roof/attic experiments. With ~ R1 of underlayment & roof decking between the hot shingles and the vented space below the roof deck that vented space has to be to be VERY cool to make a signficiant difference on peak and average shingle temps. Shingles always cool PRIMARILY by re-radiating the heat back at the sky, with convection on the exterior being a strong secondary factor. Vented roof decking is a fairly weak secondary factor. Steeper roof angles (for better convection), and low solar gain/high-emissivity colors (for better radiatioal cooling) make a far bigger difference in roofing material temperatures than is possible with attic venting. Concrete roofs have a significant inherent cooling energy reduction benefit due to their thermal mass, and being highly emissive in the deep infra-red, they radiation-cool quite well. Between the radiant cooling and the built-in delay in temperature at the roof deck due to the thermal mass of the concrete, both peak and average cooling loads are reduced. |
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kelhuck
New Member
Posts:9
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| 16 Apr 2012 01:06 PM |
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Just wanted to say I appreciate the folks who recently completed their ICF houses checking back in and giving their updates. We're close to starting an ICF build, and it helps to see true life experiences! |
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MikeSolar
Basic Member
Posts:376
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| 06 May 2012 05:31 PM |
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I've been doing solar and low energy construction for nearly 30 years. Many years ago a client wanted to use EPS on the outside of the walls due to the embodied energy and i didn't agree with him. I said to go with SM even though it takes more energy to make.
We put a piece of SM and a piece of EPS on the ground and the next day the EPS had soaked up 4 times it weight in water. The SM didn't. If someone can prove to me that an ICF house will always be completely water free, below grade especially, for 40 years I might use it but NO built up membrane is completely liquid tight. EPS rots when left in the water over the years, SM doesn't.
Extruded (SM) or PU is the only real way to go, always on the exterior of the foundation with no insulation on the interior. That's my 2 cents. |
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| www.BossSolar.com |
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Lbear
Veteran Member
Posts:2740
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| 06 May 2012 06:23 PM |
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Posted By MikeSolar on 06 May 2012 05:31 PM
I've been doing solar and low energy construction for nearly 30 years. Many years ago a client wanted to use EPS on the outside of the walls due to the embodied energy and i didn't agree with him. I said to go with SM even though it takes more energy to make.
We put a piece of SM and a piece of EPS on the ground and the next day the EPS had soaked up 4 times it weight in water. The SM didn't. If someone can prove to me that an ICF house will always be completely water free, below grade especially, for 40 years I might use it but NO built up membrane is completely liquid tight. EPS rots when left in the water over the years, SM doesn't.
Extruded (SM) or PU is the only real way to go, always on the exterior of the foundation with no insulation on the interior. That's my 2 cents.
Doesn't PU lose its R-Value over time and off-gas for years after manufacturing? I know that with ICF homes, they do NOT put a water barrier over the above ground ICF/EPS forms. The 2006 & 2009 IRC does not require a water barrier for EPS. On a wood framed home, the water/moisture barrier (Tyvek) is applied to the OSB shear walls and then EPS foam is applied on top of this and then the stucco coat is applied. The EPS gets wet A LOT as stucco is not waterproof and the Tyvek is behind the EPS, not before it. From what you are saying, we will start to see homes that used EPS to start experiencing "EPS rot"? |
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jeepster
Basic Member
Posts:153
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| 06 May 2012 08:18 PM |
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We put a piece of SM and a piece of EPS on the ground and the next day the EPS had soaked up 4 times it weight in water. I feel sorry for the guys that have beer coolers that are made of EPS . . . . or the poor soul that bought that McDonald's Soda . . . or heaven forbide, that poor guy who bought a sail boat with EPS core for floatation or hell, the safety floatation device itself. Sense the sarcasim? EPS doesn't take on water. You obviously don't work with the stuff, or you would know that. |
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MikeSolar
Basic Member
Posts:376
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| 06 May 2012 10:08 PM |
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Pick up a sheet that has been left out in the rain or dew on the lawn. I'll bet the r-value of that is not very good. You make a good point about the flotation devices but we are talking about something that hopefully will be good as new in 50+ years. No one expects flotation devices to be around that long (although I do know some pretty old ones) and making a foam cup is not the same process. I expect the bonds between the beads to break down over time, not the bead itself.
And yes, I do work with it, even though I don't like it. Have you pulled it off a 20 year old building? |
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| www.BossSolar.com |
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Lbear
Veteran Member
Posts:2740
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| 06 May 2012 11:07 PM |
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Posted By MikeSolar on 06 May 2012 10:08 PM
Pick up a sheet that has been left out in the rain or dew on the lawn. I'll bet the r-value of that is not very good. You make a good point about the flotation devices but we are talking about something that hopefully will be good as new in 50+ years. No one expects flotation devices to be around that long (although I do know some pretty old ones) and making a foam cup is not the same process. I expect the bonds between the beads to break down over time, not the bead itself.
And yes, I do work with it, even though I don't like it. Have you pulled it off a 20 year old building?
You have to realize that what you are saying goes against the International Residential Code, engineers, studies, ASTM C578 and countless of other research. If EPS is completely unstable and will "rot" and fall apart, millions of homes, including commercial applications, are now at risk of complete failure of their EPS. Energy Materials Testing Lab (EMTL) has shown that EPS insulation does not absorb appreciable moisture, even under conditions characteristic of prolonged, cold, damp winters. The small amount of moisture absorbed (an average of 0.2% by weight) has little or no effect on the compressive or flexural strength and the EPS insulation retains between 95% and 97% of its thermal efficiency. Do you have any studies backing up your claim??? |
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MikeSolar
Basic Member
Posts:376
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| 07 May 2012 06:55 AM |
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Posted By Lbear on 06 May 2012 11:07 PM
Posted By MikeSolar on 06 May 2012 10:08 PM
Pick up a sheet that has been left out in the rain or dew on the lawn. I'll bet the r-value of that is not very good. You make a good point about the flotation devices but we are talking about something that hopefully will be good as new in 50+ years. No one expects flotation devices to be around that long (although I do know some pretty old ones) and making a foam cup is not the same process. I expect the bonds between the beads to break down over time, not the bead itself.
And yes, I do work with it, even though I don't like it. Have you pulled it off a 20 year old building?
You have to realize that what you are saying goes against the International Residential Code, engineers, studies, ASTM C578 and countless of other research. If EPS is completely unstable and will "rot" and fall apart, millions of homes, including commercial applications, are now at risk of complete failure of their EPS.
Energy Materials Testing Lab (EMTL) has shown that EPS insulation does not absorb appreciable moisture, even under conditions characteristic of prolonged, cold, damp winters. The small amount of moisture absorbed (an average of 0.2% by weight) has little or no effect on the compressive or flexural strength and the EPS insulation retains between 95%
and 97% of its thermal efficiency.
Do you have any studies backing up your claim???
(somehow it didn't separate our comments)
Admittedly, I don't have published data, only my own experience, which is varied and ranges from having my own products formed out of EPS to doing renovations on 15+ year old ICF houses where we removed the covering below grade and showed EPS cohesion degradation where hydrostatic pressure pushed water past the membrane.
I will start to look for others with similar observations. I do think it is rare to comment on this kind of thing because, my impression is that most people who build with ICF have done their homework and aren't going to do a lot of major structural renos. I will post back if I find something more official.
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| www.BossSolar.com |
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teslastones
New Member
Posts:53
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| 07 May 2012 07:59 AM |
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The real issue is not absorption--which is relatively low and thus is all the industry wants to talk about.
The issue is that it never de-sorbs.
That aspect is why float logs will eventually become waterlogged and sink |
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ICFHybrid
Veteran Member
Posts:3039
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| 07 May 2012 09:10 AM |
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That aspect is why float logs will eventually become waterlogged and sink I hope you are talking about wooden float logs. Nothing lasts forever, but float "logs" made out of EPS foam are effectively lifetime floaters. Some of the things Mike describes having seen - "rotting" and waterlogging of EPS building materials can happen as a result of poor quality EPS engineering and production. Quality (mainstream) ICF blocks are going to last a very, very long time. |
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teslastones
New Member
Posts:53
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| 07 May 2012 09:23 AM |
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No, sorry, I meant exactly what I said. This is from a midwestern state but this kind of information is available worldwide as the issue is just as I have pointed out.
Dock Foam Issue Still Afloat
6/2006
PUB002041
In 1995, AmerenUE (formerly Union Electric) banned the use of unencapsulated Expanded
Polystyrene (EPS) as flotation material for boat docks on the Lake of the Ozarks. This resulted in
a noticeable generation of expanded polystyrene solid waste on shore, in the woods and in area
landfills. Similar problems with EPS have been reported on other Missouri lakes where boat
docks are prevalent.
The breakup of these foam floats due to passing boat traffic or seasonal rising and lowering of
the water level due to routine hydro electrical generation practices prompted the ban. The
floating foam pieces are considered a hazard to boat traffic and blight along the shore, especially
noticeable during the annual winter and early spring drawdown.
AmerenUE works closely with area dock builders through an association which sets construction and materials standards for new docks being built along the 1,500 or so miles of shoreline.
As old docks are dismantled, the waterlogged foam is taken away. Unfortunately, do-it-yourself
floatation replacement projects or commercial services seeking to avoid disposal costs have
continued to abandon white EPS, orange and blue floatation foam at the back of remote coves or
the material is pushed out into the lake.
In 1992 an organized effort to clean up 50 years accumulation of trash and floating foam from the
shoreline emerged as the Adopt the Shoreline program. This, linked to the annual spring Shoreline Beautification Project, has gathered EPS at on-shore collection sites for proper disposal.
Other deposits of dock foam can be found in isolated dumps near marinas, at the end of coves,
stacked near old boat yards and a few established by commercial solid waste handling firms.
For the most part, foam picked up by these commercial entities is delivered to area landfills for
burial. However, due to their waterlogged condition, the foam pieces are very heavy and therefore
costly as landfill tipping fees are applied.
A review of solid waste publications and plastics industry newsletters, as well as Internet information sites reveals no commercial market for polystyrene dock foam. However, some interest
has been expressed in recycling clean foam as packing material or soiled foam as gravel
supplement in septic tank drain fields. Used foam is also being used in some places as fill along
side concrete construction or as interior material for concrete landscaping walls.
AmerenUE officials had tried mixing ground up foam with paper to use as a waste-to-energy fuel
in the corporation’s electrical generation system, but the correct mixture has not yet been found.
A firm, which had hoped to grind the foam for use in potting soil, has rejected the proposal due to
the saturation of the material with waterborne petroleum products. The foam soaks up the spilled
gasoline and oils left by heavy boat traffic and retain the smell. The effectiveness of the foam as
a petroleum-filtering medium has apparently not been fully investigated.
Virgil Flanigan at the Center for Environmental Science and Technology at University of Missouri
– Rolla is a leader in present research into the dock foam solid waste issue. For five years he |
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ICFHybrid
Veteran Member
Posts:3039
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| 07 May 2012 09:55 AM |
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The article touches on a number of characteristics of EPS foam, most notably that it lasts nearly forever and it doesn't "rot". Mechanical action is the biggest problem with dock foam. If you haven't adequately secured the foam floatation it will wear away due to the action of wind and wave, causing it's own form of pollution. We used to replace float docks periodically as the wooden logs would get waterlogged, exposing the upper structure to water and wave action. The current floats were installed nearly 25 years ago and show no sign of waterlogging. There is a drive now towards encapsulating the floats in polymer, but that is more of an environmental issue than durability. All this discussion is a red herring with respect to the use of EPS foam in ICF block and the like. If your ICF blocks are sitting exposed to 100% water, you have other problems. |
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Dana1
Senior Member
Posts:6991
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| 07 May 2012 11:18 AM |
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EPS has a better closed cell structure than most other insulating foams, and does not become waterlogged even when buried.
If fully submerged in liquid water it takes on ~7% water into the interstitial spaces between beads over time (weeks/months) losing about 10% of it's total R-value, but it gives that water back up when allowed to dry, regaining it's original insulating value. |
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teslastones
New Member
Posts:53
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| 08 May 2012 05:07 AM |
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I,of course, defer to you superior powers of deduction and would in no way imply they are influenced in the least bit by pre-disposition.
What threw me was probably the following excepts from the State of Missouri official statement as delineated in the bulletin.
Examples----
the waterlogged foam is taken away.
However, due to their waterlogged condition, the foam pieces are very heavy and therefore
costly as landfill tipping fees are applied.
There is more but I only copied the first page.
Enquiring minds will look up this and similar position statements by regulatory bodies.
I personally have been conducting tests on waterlogged EPS floats. So far they are still not giving up the absorbtion. It has only been 7 years in the Nevada desert, however. |
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arkie6
Veteran Member
Posts:1453
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| 08 May 2012 07:21 AM |
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What density is the EPS foam in question? |
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