Browse Forums Owner Builder Forum Re: Polystyrene Wall Thickness and Material Recommendations 21Nov 10, 2014 8:13 pm Polystyrene-> hardiflex lined as second floor external walls has been around for a long time we have seen it come in and out of fashion over the years.About 12 months ago a client demolished his existing house made of this material and replaced it with double brick...the second story extension was a mess I dont know if you can put it down to bad workmanship or whatever but what was noticable was the lack of a cavity, water penetration and the external acrylic breakdown and poor patchups.. Surffice to say, It wasnt a servere environment eg Coastal, which got me wondering what if it was a marine/coastal area I doubt you would get 30-40 years life out of this material maybe 20-30 years? If I could get the engineering properties of this eps material and providing there are solvers avaliable it is possible to simulate the effects of solar/wind/thermal/moisture/durability with time based simulations although I would hate to think of the time and number of computers required and I dont know how accurate the results would be....so IMO the jury is still out. The one thing that doesnt go out of fashion and which makes sence is a cavity be it built into brick, concrete or eps.my2c Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Polystyrene Wall Thickness and Material Recommendations 23Jun 20, 2015 2:37 pm Just adding question to this old topic Stewie/akapacker Is the main reason for using battens to install the XPS/EPS to increase the R value of the walls by introducing the air cavity? Builder has recommended EPS for our external walls but using direct fix to studs with wallwrap in between and not cavity fix with battens... Re: Polystyrene Wall Thickness and Material Recommendations 24Jun 21, 2015 12:35 pm Partly. The air gap does provide another 0.12 to your total R value but whether you use battens over top of wall sarking, then fix the poly sheets to that also depends on the particular system you are choosing and whether the joins in the sheets coincide with your studs. With some of my clients that have chosen EPS for their cladding, I've talked to a couple of the builders doing the work and they said it was easier to build the timber stud walls first then wrap those on the outside with sarking or whatever, then batten the walls as they went on the outside to allow for the sheet joins. The battens in the diagram above are just there for illustration purposes and could be fixed either horizontally or vertically. Stewie Different to what others have said but thanks for that insight. 2 5186 Not recommended! The image presented is for a sublevel area. The footings are down deep with a load bearing wall supporting the upper floor level. If you did that drain… 8 10525 Always get multiple quotes, no matter how reasonable/cheap you think it is. I remember getting a few quotes for a pool fence, roughly around the same price, thinking the… 5 9656 |