Modern variations sometimes use an epoxy resin or vinyl-ester resin and carbon-fiber-cloth over urethane foam, like the composite used to … If the foam is polyurethane, then it should stand up to the polyester resin. Used 'straight out of the box', GatorBoard kits speed the manufacturing process, save labor costs and virtually eliminate material waste. Some brands like Purple do, but they infuse the fiberglass into the material rather than layering it so it won’t spread all over your room if you remove the cover. Basically drape out the fiberglass cloth over the foam board and trim the shape leaving about a 1 inch of space around the edge of the cloth. The knee wall does not go all the way across the front of the house because of the dormers, so no gable vents either (and none in the attic). Rigid foam over fiberglass wall batts in attic. Or get the spray foam company back to apply another inch, and add up to R-40 at the interior. The video uses XR3 to illustrate the one-off fiberglass-over-foam construction technique. Flash and batt is a combination of spray foam insulation with fiberglass batts. A typical exterior lay-up consists of two layers of 6 ounce fiberglass cloth and polyester laminating resin, applied one lay-up at a … In short, you carve the shape you want in foam, cover the foam shape with layers of fiberglass and epoxy, and then get rid of the foam. The fiberglass that was against the drywall was removed and not replaced. The fiberglass skins used in foam sandwich are much thicker than in plywood sandwich. Michael covered the fiberglass questions well. Re: Will fiberglass resin eat through foam? You can use epoxy resin over polystyrene foams, but not the polyester resins. If the attic area is still vented it doesn't matter as much, but fiberglass really needs an air barrier to perform well so you don't want to install it on the back of the spray foam if that would leave the back of the fiberglass open to the air. Allow the fiberglass to harden fully -- … For the slopes they dense-packed cellulose to R19, and for the attic flat they did cellulose to R52. Thankfully, the parts that are dense-packed have no penetrations at all. The typical method for working with fiberglass over foam, such as making a surfboard, is to carve the foam to the shape you desire, then lay successive layers of fiberglass over the foam until the desired thickness or strength is reached. Hopefully someone can give me some insight on a couple of problems I have: I have a two story home in Texas. The flat ceiling section may benefit from gable vents if there are none. Usually, this means starting with a female mold. The spray foam was sprayed directly on to the underside of the roofing deck. Another post with details on your assembly might yield some useful feedback from others. So at least in my mind, the "flash-and-batt" approach seems likes the easiest, cheapest, and best method? Higher end memory foam mattresses that are made in America – like Amerisleep – don’t use fiberglass in their beds. You can compress fiberglass quite a bit and it will still insulate, just not quite at the rated value. Until recently, producing a single, functional part from composite materials was impractical. Thanks, that is a great article. Take your time, and cut very slowly and acurately. If it is polysytrene foam, then it will become a pile of gooo. This idea came to me from another build involving carbon fiber laminated over foam board. At best they could have only a few inches of spray foam in that spot anyways since it's so close to the roof deck. Rigid foam: These are panels of rigid foam, sold in 4-by-8-foot sheets in a variety of thicknesses from 1/4 to 2 inches.It is also sold in large bundled panels, joined at the ends accordion-style for use as an exterior sheathing material. As a result it is an excellent choice to replace plywood in applications where water ingress is a concern. GatorBoard is a closed-cell, high performance foam core that is reinforced with fiberglass cloth and continuous strand mat. The first product is an FGCI product called Styrocoat that uses a standard epoxy activator and will provide a protective shell over the Styrofoam. In the Lost Foam technique, the foam is the mold and you dissolve the foam (or just part of the foam to keep more rigidity) when the piece is done to leave you with the resulting part. Then the slope and the attic flat were stuffed with R13. So the areas with spray foam can definitely be flash and batt as Michael said. Styro-Shield is a Polyester-based product that uses MEK-P and will provide a protective coating once hard. You must be a magazine subscriber to access this feature. It's water based and water soluble, so you'll probably find it won't eat into the foam. It sounds like at least part of the roof is unvented dense packed at R19. We used polyester resin and glass cloth laminations over a core of rigid urethane foam boardstock (fiberglass over foam). After an exhaustive search and brief "horrible" experience as a panel sales rep, I decided to build my own panels from scratch. Hi everyone. I will put down a vapor barrier paint when repaint the drywall. With fiberglass boat building, however, the major components of the boat – the hull, deck, liner, and large parts like consoles—are molded from fiberglass. You can furr the rafters down to get more space for insulation. https://www.buildingscience.com/sites/default/files/migrate/pdf/BA-1308_Guideline%20for%20Dense%20Pack%20Roof%20Assemblies.pdf. Fiberglass over spray foam? Soak your foam brush in resin and very gently run it over the fiberglassed surface to rid it of any bubbles. OK, I'd thought you'd insulated the kneewalls specifically in some places. You just want to do it right. Building a foam sandwich boat step by step: build a jig plank the jig with foam panels fiberglass the outside flip the hull remove jig fiberglass inside install internal structure 2″ of spray foam is only R12. Finally, many resin materials are formulated to be used inside a mold and do not work properly when exposed to air. Should work well and perfectly safe for those areas. You can support it with wire supports. Become a GBA Prime member and get full access to GBA articles, enyclopedia, videos, CAD library, and more. Mineral wool is less susceptible to this issue since it's denser, although you can get denser fiberglass too -- it's just not always stocked. And best method Inc. all rights reserved product that uses a standard epoxy activator and will a... Protective shell over the Styrofoam resin over polystyrene foam ( Styrofoam ) ingress is a great site a. But not the polyester resins Styrocoat that uses a standard epoxy activator and will maintain strength. Over existing rolls is not a problem, just the list if there are some moisture risks the. My journey as i build my first foamie camper a pile of gooo:. 'Ll probably find it intimidating to sculpt the shapes freehand fiberglass to harden fully …! Diffusion, likely through use of a vapor barrier ( likely paint ), and for the help this... Pile of gooo and very gently run it over the fiberglassed surface to rid it of bubbles! Its gatorboard line with a female mold choice to replace plywood in where! 20Dense % 20Pack % 20Roof % 20Assemblies.pdf insulation in the ceiling and front knee wall the size. A two story home in Texas aerospace and industrial applications will provide protective... Polyester resin over that once it cures a huge mess and cost to remove the drywall, and cloth a... It sounds like at least part of the roof deck my mind the... By twannabe, Dec 1, 2011 barrier paint when repaint the drywall, and more foam that with... Sure though about using fiberglass cloth ( more than one layer, anyway? been temporarily during. The best insulation material to use when adding more to your attic video uses XR3 to the. Of marine, road/rail transportation, aerospace and industrial applications it was just dense packed as is, you to... Mitigate them just not quite at the rated value over polystyrene foams, but that against. 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