EPS, XPS & Polyiso insulation | everything you need to know

eps xps and polyiso three very similar forms of board insulation used in home construction and in the building construction industry in general in today's video we're going to look into how they are made and compare their physical and chemical properties let's start with eps or expanded polystyrene the monomer styrene is composed of a benzene ring c6h6 and ethylene they are both made by the petrochemical industry under heat or by an initiator like benzoyl peroxide the double bond between the carbon atoms is converted into a single bond and a polymer chain called polystyrene is formed this liquid polystyrene is dropped in water to form droplets or beads this video shows how polystyrene pellets expand in the presence of steam commercially the polystyrene beads are expanded with blowing agents such as propane pentane and methylene chloride the eps beads are contained in a mold and then heat or steam is applied to it which causes the small beads to expand and fuse together while each individual bead is the closed cell there is significant open space between the beads these eps beads can also be molded into large sheets or blocks and then cut by hot wire machines into thinner sheets or any special shapes or forms eps is made of 98 air and just 2 percent plastic it can be easily dissolved in acetone and leaves behind barely any residue this high percentage of trapped air makes it an excellent insulator it's widely used in the building construction industry because it's so versatile it can be used on roofs in walls in floors below grade for insulated vinyl siding in insulated concrete forms or icf blocks in structurally insulated panels or sips and in exterior insulated finish systems or efis outside the construction industry it is used in packaging peanuts cushioning for fragile items and disposable food containers eps has many advantages it has the highest r value per dollar a four foot by eight foot by one inch sheet at home depot and costs 16.25 this one in sheet has an r value of about r 3.18 to r 4.6 the closed cell foam and air also make it an excellent insulator there's a term in the construction industry called thermal drift which refers to the loss of r value over time because the air trapped inside the insulation dissipates the big advantage of eps is that it has no thermal drift or loss of r value over time there's also no off-casting on site because the blowing agents are trapped inside the beads eps doesn't use any cfcs or chlorofluorocarbons or even hcfcs or hydrochlorofluorocarbons in the blowing process so it's the greenest choice among all the three insulation types that we're going to discuss today since it is impermeable to water it is mold and mildew resistant it is also 100 recyclable now the disadvantages of eps the insulation panels are coated in a bromine fire retardant called hpcd or hexa bromocyclododecane which is dangerous to help eps can also attract termites and ants water can penetrate in the eps because of the space between the beads it is also flammable finally it doesn't break down in sunlight and it is not biodegradable it is a major contributor to trash pollution across the world [Music] next let's discuss xps or extruded polystyrene this is styrofoam i grew up calling eps styrofoam like most people but xps is actually styrofoam now chemically it's made up of the same material as eps it's just polystyrene but rather than being formed into droplets and then expanded it is foamed up get it styrofoam foamed up styrene anyway the liquid form is mixed with additives and blowing agents and then extruded through a dye it is then expanded during the cooling process this produces a tightly packed closed cell insulation just like eps xps is made of 98 air and just 2 plastic blue xps is made by dow chemical green xps is made by kingspan and pinkxps is made by owens corning they're all the same the colors help distinguish the manufacturing company on job sites now let's discuss the advantages of xps it is fairly inexpensive a four foot by eight foot by one in sheet at home depot costs 19.98 this one in sheet has an r value of about r5 the closed cell foam and the air trapped inside it make it an excellent insulator since the cells of xps are so tightly packed it is more moisture resistant and mildew resistant than eps so it is often selected in wetter environments the compressive strength of xps is also greater than eps there's no thermal drift or loss of r value over time finally it is 100 recyclable it's also very versatile and can be used below grade below the slab and even on basement walls now the disadvantages of xps it uses hfcs or hydrofluorocarbons as a blowing agent to expand the polystyrene hfc has a global warming potential 1 300 times higher than carbon dioxide xps panels are also coated in the same bromine fire retardant as eps panels which can be dangerous to help xps can also attract ants and termites even though it's not an organic material finally it's also flammable and it does not break down in sunlight and it's not biodegradable lastly let's discuss polyisocyanurate or polyiso it is made by combining three main components mdi or methylene diphenyl dioxocyanate polyol and a blowing agent when these three components are mixed along with small amounts of catalysts an exothermic chemical reaction causes the liquid blowing agent to boil evaporation is an exothermic reaction so let's look at an endothermic one mr slave position seven please this expands the foam creating tightly packed gas-filled cells the foam has to be sprayed against the substrate to form a rigid panel so all iso panels are faced with either foil or paper the foil faced panels are considered impermeable because they create an exterior vapor barrier they should never be used with an internal vapor barrier because then you'll have vapor trapped between these two barriers which can cause mold and mildew let's discuss the advantages of polyiso it has the highest r value per inch compared to eps and xps it's about an r6 to an r6.5 poly iso is also stable over a large temperature range minus 100 degrees fahrenheit to 250 degrees fahrenheit it can be used on roof systems with hot asphalt in fact poly iso is used on 70 of commercial roof construction poly iso also has a very low water absorption and low vapor transmission it's not affected by oil based waterproofing compounds insecticides or fertilizers when it is properly protected the poly iso industry uses pentane as a blowing agent which has zero global warming potential and zero ozone depletion potential one of the disadvantages of poly iso is that it's more expensive than eps or xps a four foot by eight foot by one in sheet at home depot costs 21.52 poly iso uses a halogen fire retardant tcpp which is dangerous to health it doesn't work very well in temperatures below 50 degrees fahrenheit because the trapped gases start to condense and they no longer act as an insulator it is the least eco-friendly option of the three and it has the worst thermal drift let me know what you think about this video in the comments below and if you have any experience using eps xps and poly iso that you'd like to share don't forget to hit the like button and subscribe to my channel i'll also link my other youtube page where i post revit and bim tutorials and i'll also link some of my other videos over here that's all for now see ya

Channel: Belinda Carr

Views: 143,946

Rating: 4.9697556 out of 5

Keywords: insulation, eps, xps, polyiso, foam insulation, spray foam, construction, architecture, architect, design, women in construction, tutorial, tiny home, diy, diy build, stem, steam, science, chemistry, chemical reactions, automation, robotics, future, knowledge

Id: xdnLOv-zf_o

Length: 9min 32sec (572 seconds)

Published: Fri Aug 14 2020

Reddit Comments

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[u/bluebalztraveler]

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