| Author |
Message |
OAE Palmer (216.39.187.142)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 09, 2003 - 3:15 am: | |
I've been working on the ceiling again, doin the insulation.
Remembering that Fred had some unanswered questions about the various types of foams qualities, I picked up some lit on a couple of products www.convenienceproducts.com they make a 2part AND a single part foam for insulation purposes.
Here are just a couple of comparitives of the 2...
Radiant value
1part...R-5.4 per inch
2part...R-6.9 per inch
density
1part...1.3-1.8 lbs. per cu.ft.
2part...1.75 lbs per cu.ft.
compresive strength
1part...11psi
2part...19psi
ALSO....
I used a product that looks like foil bubblepack as the final inner layer of my insulation package
( http://www.reflectixinc.com )
I've used it many times in the past always with great results, especially in conjunction with foil clad foamboard insul and foil vaporseal.
One other product not mentioned frequently is
Ethafoam... a closed cell polyethylene, you see it used in swimming pool toys and paddleboards.
It also has some sound deadening qualities especially over 1 inch in thickness.
I am almost finished with my overhead work and this is what, how and why
Because of time, money & availability....I had to alter my original insulation plans, which called for the professional application of a proper density & strength & fire retarded sprayed foam.
Instead of the foam,
I used double foil faced 1-inch foam commonly seen at the bigbox stores.
I started with a ceiling devoid of the paper pillows of spun glass insulation that were stuck to the hot asphalt sprayed on the interior walls of the 4106 to seal the interior from the wet salty air people exhale by the gallons and the condensation due to ambiant humidity & temps outside the coach.
BTW & FWIW...all of these pillows had seams where there was NO insulation at all....meaning for each retangle in the framoiing the was only the thickness of a common grocery paper bag between the aluminum top skin and the masonite interior ceiling.
I started with the asphalt still in place and sticky after 40 years, still doing its job.
In each framing void (usually 19x27x1-3/8ths) I would apply an oversized sheet of aluminumized mylar for 2 reasons...a vapor seal and a heat radiation barrier, it also protects and seal the foam which comes next.
The 1-inch aluminumfoil faced foamboard was cut to fit each void and the corner radai were pieced in in 4-inch wide strips to minimize cavities.
The Reflectix bubble material was layer #3 and it was also cut to 1-inch bigger in EACH direction than the void it was to fill...
this 1-inch flap on all 4 sides was then chinked or wedged between the steel fram member and the alumifoil foambrd, which tightly holds all 3 layers in place w/o adhesives and leaves the steel frames free and exposed.
The steel frames were lightly scraped for excess asphalt and paper residue from the orig. OEM intall.
I went over them once with Methyl Ethyl Ketone on a rag to smooth any bumps and resmear the asphaltover the frame.
Then I applied a double stick or double faced tape 1-in. wide to the frame faces.
This tape is easily found at art supply and sign supply busineses, there are 2 types, masking paper & clear...in this application I chose the thicker of the 2 tapes which was the clear @ $11.00 a roll.
The tape was applied to the frames using a stiff squeegeto force the adhesive and get a firm application. This one came from a vinyl letter sign maker they are about .30cents each in craft stores as well, made from polyethylene (like ziplok bags)this is also the tool I used to chink the bubblepak into the tite space between the alumafoam and the frame. Using the corner of the squeege to start and then rocking it back into the void pressed the material clean and tight giving me an air and moisture seal to back up the asphalt.
Once the frames were double-stick taped and the protective paper removed the framework was ready to recieve another layer.
This next layer of material is used in overseas shipping and in longterm storage of various items including food.
It is a multilayer material you can use to make vacuumed packed/heatsealed envelopes...over bags, boxes, spare machine parts, irradiated foodstuffs.
I was in Antarctica for several years and we used it there to vaporseal & reflect heat in canvas quansett huts with wooden pallete flooring.
This material is made with 3 layers of thick polyethelene (freezerbag) which sandwich 2 layers of aluminumfoil, )slightly thicker than the kitchen stuff).
This material has a shiney side which goes up to reflect radiated heat and is stuch to the doublefaced tape on the frames.
I cut the poly-alum-film square on the front end and pulled out a few feet more than the actual length needed. Starting in the front I squared the film off with a frame and then thumbprinted a spot on each frame going down the middle of the coach.
Once I had all 25+ ft hanging straight down the centerline I went back to the front and keeping the edge of the foil against the edge of the frame I used that squeege again to press the film to the tape. This worked on each frame member quite well with only a couple of tiny wrinkles.
At this point I have a sealed and double insulated ceiling almost ready for the interior facing paneling.
The ceiling is now sealed and "enveloped" in poly and aluminum and the frames are clearly visually located on the back due to the squeeges embossing effect.
This allows me to locate those frames to bind a frost barrier to.
I am using a plastic material called Sintra, which is the trade name for expanded PVC foam.
I am using 1/4 in. thick material cut into 1inch strips that are screwed to the frames with #6 countersunk sheetmetal screws. Over this plastic is a strip of 5ply marine grade birch plywood 1/8th inch thick and 1inch wide which is held to the Sintra with GE Contractors grade Silicone 1100.
This product allows the material in contact with it to creep or expand with temp variations while still holding fast and tite. The surface of the Sintra must be lightly roughed up with 80grit sandpaperto get the best mechanical grip of the silicone adhesive. (BTW this is the BEST general allaround silicone sealer and adhesive available, comes in a number of colors and dries to the touch in 1hour at 75f....you can ONLY find it at commercial contractor supply stores N/A at home depot, menards and lowes or your corner ace or true value..sorry!)
The woodstripping on the steel+Sintra framing is now ready for the ceiling panels.
I have my choice in ceiling panel wood, Mahogany or Poplar faced 5ply marine grade 3/32nds thick.
This is going up the long way buttspliced on the centerline over the isle.
It is going up with adhesive and no fasteners visible, there will be a center T-strip down the middle tho.
More on that installation when it is finished and I have the time to put it here.
I cut each section to lightly press fit into the frame sections. |
Jayjay (198.81.26.230)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 09, 2003 - 11:27 am: | |
Dr. Palmer sir: thanks for the tip on GE silicone II. Tell me, in all of your research have you found any information or brand/type specific imformation on the flame spread or toxicity of fumes/smoke during a fire? I am aware that the various foams/boards are nasty when ignited, but I would like to know which types are more benign, or to reverse the coin, which are the nastiest. I would appreciate a response from any 'Board Member that has difinitive infirmation on the smoke from insulation. Are there any legal (Building Code) restrictions on the location or area of use of various types? Thanks, and Cheers...JJ |
john marbury (Jmarbury) (65.100.118.44)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 09, 2003 - 2:06 pm: | |
A while back some one mentioned using insulation
made by Radiant Technology out of Dallas, Tx. I'd like to talk to that person. Click on my name for an E-mail address.
Thanks, John |
Ben Mallon (68.1.245.13)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 25, 2003 - 12:31 pm: | |
In the Aircraft Spruce and Specialty catalog (they will mail you a copy free if you call them at 1-877-4-spruce) they list several foams that should not be cut with a heated wire as they emit toxic fumes. I belive all foams with urethane anywhere in the name will emit hydrogen cyanide when heated/burned. Nasty stuff, kills quick by blocking all the receptor sites on red blood cells. California used it in their execution gas chambers at one time. I guess if the foam is fire-retarded and faced with something non-flammable this reduces the threat. I suppose it would have to be, since you can buy and use stuff like R-max (foil-faced urethane foam insulation boards) in a residence.
BTW, the catalog has a lot of good info and a lot of useful items like marine and aircraft grade plywood, adhesives, glass fiber- Kevlar- carbon fiber-fabrics, sealants etc. Some are pricey, some are not. |
OAE Palmer (216.39.187.84)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, April 26, 2003 - 12:30 am: | |
Thanks!!
They will get a call from me on monday, one can never have enough resources of quality materials.
As for hori. cutting of sprayed foam, nothing works as good as a plain ol carpenters saw and a bucksaw blade with a pair of screw handles you hold like a bicycle handlebars in front of you. |
|