I am building a new house and I would like to cut the 4×8 sheets of solid foam insulation to place between the rafters in the attic, instead of using batts. Does solid foam insulation have to be covered on both sides? How fire resistant is it? The purpose of using solid foam is to cut down on dust in the house, since I live in the dusty and hot desert southwest. Spray-in insulation is not an option. Any opinions would be appreciated. Thanks. Bonnie
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soild foam does burn and gives off really bad gas . I guess that the dessert that you are in gets hot .what is wrong with fiber glass?? you could build a double roof whith an air space in between the two surfaces and have ventilation IE. ridgevent and soffit venting.
I live in the desert southwest with massive dust storms. Houses insulated with conventional fiberglass batts have a problem with dust infiltration, even with windows closed. I was thinking of using solid foam insulation (and lots of caulking) to reduce air (and therefore - dust) infiltration.
As I follow-up to your message, I have already built the house and am creating essentially two roof systems; the actual roof itself with soffit vents and solar fans, then insulation at the ceiling level, to keep dust out of the house and expensive air conditioning inside the house. I have finished the exterior and am now ready to start insulating the interior.
Correct me if I am wrong, but I think you provided your own solution. You have built a properly vented roof and now want to insulate the ceiling plane, correct? Reducing air infiltration or exfiltration at the ceiling plane is a function of air tight drywall and sealing all penetrations into the habitable space. Tightly fit solid foam insulation in the joist bays may reduce air movement in either direction but the drywall, vp, and fire stop caulking is much more effective. Dense pack cellulose would be my choice for insulation. It has a higher R value per inch than fiberglass, and reduces air movement to nearly nothing. It is also has a lower flame spread and smoke index than foam.
Dave
Yes, I have built a properly vented roof and do want to insulate the ceiling plane. An insulation subcontractor advised against blown-in insulation in the ceiling because he said small pieces of the blown-in insulation would go into the solar-powered attic fan. He recommended batts instead, but I am not convinced I can stop air infiltration with batts. That is why I was thinking about using solid foam insulation. I am, however, concerned about flammability using solid foam.
A layer of 5/8 firecode drywall between you and any flammable products will do the trick.
Gabe
A layer of drywall over the insulation which I am placing in the attic?
Bonnie,
that is part of a great idea.. but you need to finish it.. Are you familar with SIPS? (structural insulated panels?) that is what they do, but if you use them you can build your whole house with them. Thus saving the cost of all of those 2x4's and plywood etc.. Very strong.. super insulation and simple to build with..
To answer your questions, yes foam is flamable and needs to be covered. Sheet rock is normal but there is a new fire retardant paint available that also fills that requirement.
Yes, I am familiar with SIPS. Such a system is not readily available here. I have actually built and finished the exterior of the house, and am now ready to insulate the interior.
You might want to look at http://www.buildingscience.com
Look it the information for your region. Also checkout the research papers. There are articles about the advantage of making the attic part of the conditioned space. Specially if you have the HVAC ducts in the attic.
I will check out the website. There are no hvac ducts in the attic; I have run them through the floor joists.
I don't want to make the attic part of the conditioned space because I want to create a barrier between the interior, containing very expensive air-conditioned air, and the desert heat outside the roof.
Hiya Miss, I was curious as to what type of roofing material you are using out there?
I am using flat concrete tiles on the roof of the house I am building.
why isn't icynene an option, covered as Gabe suggests for fire protection? It'd be tighter than cutting boards to fit.
I have lived for three years in Lubbock, Texas so I understand the dust problem but it is not through the ceiling SR or insulation that you will see dust getting in. Your best bet is the fibreglas batts and a good job on the sheetrock. The air and dust infiltration will be at your windows and doors. Cutting foam to fit between bays is a tremendous addition of cost in both labor and materials with a nebulous gain. If you wanted to use it still, I will suggest a better way that is a hybrid.
install the fibreglass batts between bays
Place solid foam insulation over the framing and tape all the joints
Then screw your SR on over the foam.
.
Excellence is its own reward!
Out in the wilds of west Texas, where I live, up-to-date construction materials are difficult to find. Any kind of sprayed-in insulation is a bit of a novelty!
Perhaps worth a call...
REYNOLDS FOAM ROOFING & INSULATION
502 E 76TH ST
LUBBOCK, TX 79404
806/745-4850
Given the goals you mentioned, and seeing the benifits of sprayed foam first hand, not much to lose from a phone call...
Hi Cloud.
I'm the one who mentioned Lubbock. She has only said that she is in the desert southwest so she could be a thousand miles away in Tucson.
Be that as it may, you never understand a dust storm until you've lived through a few. I was offering my info to show her that I understood the problem. I agree that if she can find someone to spray urea or icythene foam, she has many problems solved..
Excellence is its own reward!
A little trick I use to seek out air leaks in a finished house is to wait for a good windy day and check around all openeing with a lit incense stick. I turn off the HVAC system and check switchs, plugs, around doors and windows, exhaust fans, dryer vents, and light fixtures, etc. without going to the expense of a blower door test, most of the homes I have tightened up with this method realize anywhere fro 5-15% immediate energy savings.
I guess in a dust storm area you could forego the incense sticks and just look for the dust stains around the leak points :)
Missed that one! But we can triangulate in to a position on her. "Out in the wilds of west Texas, where I live"... At least we know the state! Plus, if there's no one local, I know a travelling foamer. Does domes and flat roofs. Colorado based, but headed to East Texas soon in his 18-wheel shop. Might be passing right near her.
Thanks for the insulation tip. I will call the company.
One of your early questions which you seam to have reworded to Gabe is whether foam has to be covered with sheetrock on both sides.
No.
You need the fire barrior on the living side of the foam, both to prevent fire sources from starting a smoulder in the foam, and to hold off the amt of vapours ypou would breathe if a fire did start in the foam. SR on the opposite side would do little.
Excellence is its own reward!
Thanks for the clarification. Of course, the living side of the insulation would have drywall anway.
I ask this as a layman.
If sand dust infiltration is a concern, should there be a concern for what happens in a vented attic ?
Is it possible, especially if this dust problem is severe enough, that is could blow into the attic during the convective venting process and start accumulating/collecting ?
With Sprayed in Foam, you don't need any ventilation. As a matter of fact in most cases it's a waste of space.
Gabe
It's not only possible. It happens with a vengence!
Doing a roof tearoff out there involves dust masks, especiallly with cedar shingles where very void will be packed tight with fine nasty dust. A roof tear off is almost as bad as removing plaster indoors!
Like I said above, you can't understand it until you have lived through a few. It gets every where. Grit in eyes, ears, pillowcases, shoes, teeth, books, etc. I swear, sometimes it seems like it can find it's way into a ziplock baggie and pull the zipper shut behind it. You'll find dust piled up near any crack or openning, even what you thought were tight fitting window sashes.
So the next time this house gets remodeled, there will be a couple of five gallon buckets of dust up in the attic..
Excellence is its own reward!
Thanks, Piffin -
I can now imagine how bad it is just with my experience with pollen clouds that float around in spring and fall in Virginia.
Which brings up.....Iraq.
I've seen zero mention of eventual problems with silicosis years after the soldiers return.
Troops were heavy breathing sand dust - scarfs, bandanas and whatever else I saw them wearing did not appear to be adaquate.
I don't recall seening any wearing one of those diposable paper masks with exhaust valves.
No different then sawing concrete wearing only a regular paper mask.
It sure would be nice to either filter the soffit vents or eliminate them completely and provide a different source of fresh air inlet to the attic space. A source that could somehow be controlled to limit dust entry.
carpenter in transition
A swirling curve profile along the entire length of the soffit entry so the dusty air hits it and separates the stuff.
Sortof like a cyclone separator.
A spring-loaded trap door could be pulled down to empty it with a long stick with a hook on it.
Someone go get a patent on this idea.
You're right soldiers don't wear proper masks for dust. Even when training in the desert in Idaho there is often 18" of fine alkali dust on the roads. Just walking raises huge dust clouds. Vehicles have to follow 1/4 mile or further behind each other at slow speeds so you can have some idea where the road is.
Any desert sucks for dust. Particularly if you're at the end of a convoy.
I've never been smart enough to bring a mask. Never seen anyone else do it either. A cravat (OD green triangular bandage) over your face makes a big difference, but I'm sure it's not nearly as good as wearing a painter's mask.
The army will give you a cravat to use for dust most times, but it'd be nice if they issued green dust masks. You wouldn't be allowed to wear a normal brite white mask as it would stand out a mile away, camaflage you know.
You've addressed an issue that the military, to my knowledge, has never dealt with.
I've seen them wear goggles, which could easily be modified to incorporate a face breather.
I'm picturing a stretchy balaclava made of filter material with built-in exhaust ports and integral goggles.
Less cumbersome then those cartridge equipped gas-mask like devices if there is no danger of chemical or germ attack.
Not to be a doomsayer, but I do expect silocosis will be a post-war news subject at some point.
Actually, the dust goggles work real well, even if you wear glasses. They're standard issue. I even picked up an extra pair. Still wear them on occassion. A mod that allowed you to snap on a dust mask underneath would be a good idea.
Honestly, don't know what silocosis is. If it's like most lung problems I doubt a few months exposure would affect most people. Generally lung problems are brought on by long-term exposure over a very long period. But, again, I know nothing about this in particular. I've certainly breathed enough dust and dirt in my lifetime. Military, windstorms blowing acrost the farmland by my house, driving dirt roads, ect.. So far so good, but I'm young yet.
Typically, people who exercise a lot aren't as likely to get lung problems. Good news for military guys, bad news for desk jockey's like myself.
Silicosis will produce many results in Google search.
However, there are many slimeball groups' web sites geared toward litigation.
Fortunately there are several government (such as OSHA) and university research site that are informative.
Although the serious battles were not long-term in Iraq, I consider the conditions severe enough to be of concern for the folks who were over there.
I think camels evolved into handling such problems, but not humans.
Perhaps I'm being a bit alarmist.
Not to be flippant, but if it were a serious risk I'm sure it would have turned up before now.
Just in military operations by the US. Lots of troops spent years fighting in the desert in WWII. Trainers at the National Training Center (NTC), in death valley spend years out in the desert in similar conditions. Nasty place to train, but hard training saves lives in conflicts like in Iraq. I've heard lots of theories on Gulf War Syndrome, never heard of this issue. Some guys I know, who are in perfect health, sure get tired of being called in to get poked for tests studying Gulf War Syndrome. Sometimes they refer to themselves as Army pincusions.
Locals spend their entire lives in such conditions. Is this problem rampant among Iraqi's themselves? Many of them live in that condition all the time. I've known lots of folks who race dune buggys and such things. They eat a lot of sand, never heard of it as an issue.
What exactly are the symptoms of Silicosis?
You make good points and I don't think you're being flippant at all.
Yes, I considered the locals who live in those conditions.
The concern for sand dust inhalation was just a reaction to all those telecasts from Iraq, with newscasters coughing and clearing their throats during live broadcasts and troops interviewed during some of the sandstorms.
Here is a neutral site that has general information on silicosis.
--------------------------
http://www.nlm.nih.gov/medlineplus/ency/article/000134.htm
A respiratory disease caused by inhalation of silica dust which leads to inflammation and then scarring of the lung tissue.
Three types of silicosis are seen:
* simple chronic silicosis -- which results from long-term exposure (more than 20 years) to low amounts of silica dust. Nodules of chronic inflammation and scarring provoked by the silica dust form in the lungs and chest lymph nodes. This disease may feature breathlessness and may resemble chronic obstructive pulmonary disease (COPD)
* accelerated silicosis -- occurs after exposure to larger amounts of silica over a shorter period of time (4-8 years). Inflammation, scarring, and symptoms progress faster in accelerated silicosis than in simple silicosis.
* acute silicosis -- results from short-term exposure to very large amounts of silica. The lungs become very inflamed and may fill with fluid, causing severe shortness of breath and low blood oxygen levels.
Progressive massive fibrosis may occur in simple or accelerated silicosis, but is more common in the accelerated form. Progressive massive fibrosis results from severe scarring and leads to obliteration of normal lung structures.
Interesting. You are right, that the military probably should issue dust masks. Any time you need your dust goggles they'd come in handy, but they'd have to work so they didn't fog your goggles.
I'd assume as with most lung inhalation type problems size of silica inhaled would make a big difference. If you've ever been outside in a sandstorm, it about takes your skin off. The fine alkali dust is just miserable, but doesn't feel like you've been sandblasted afterwards. Sand comes in many sizes. Seems smaller would cause more lung problems.
Do you know someone with this problem, or is it just something that interests you?
Happy Easter
Billy
Well, it's not something that I'm obsessed with.
I believe the danger of silicosis has been mentioned in past FH issues.
Just something that I started wondering about during the Iraq war media bombardment and stories of guns jamming, etc.
Happy Easter.
I'll jump back in here now.
First, Even if silicosis were a pertinent danger - I'll explain later why I think it not so - I would rather risk that than to have my goggles fogged up so I couldn't see the enemy and expose myself to the greater risk.
But the risk is so extremely low for all except those whose constitution is such that they would probably not have made it through boot anyway that it is not worth worrying about. There is the inconvenience of the short term inflamation or sinus infection but it takes long term exposure to silica dust to create the scarring that is known as chronic silicosis.
Similar to asbestosis in this way, it is the scarring of the lung tissue that is the problem. Young tissue, under constant stretching movement of exercise and heavy breathing will form less scarring than old tissue that is stagnant in place. It is also recieving good nutrition from healthy flow of blood and oxygen
The one variable that is more likely to contribute to scarring is cigarette smoke. The tars in it form a surface that stiffens the lung tissue so that irritants are less likely to be expelled and more likely to scar.
Sure, after three years of texaas dust and thirty some years of construction around plaster, cement, sawdust, asphalt fumes, pitch smoke, and even asbestos, my breathe isn't quite what it was when I ran track in HS but I have so scarring or other spotting that shows on X-ray. I sincerely doubt that a few months in the desert is going to line up a squadron of GIs with claims for silly cosis.
.
Excellence is its own reward!
Well put, Piffin.
My concerns are laid to rest.
However, it's probably something the military should address if there are more deployment in dusty regions.
If civilians have plenty of choices they could easily have masks that don't fog up the goggles, etc.