Free DIY Greenhouse Projects & Tips : Tip. Nut. comdoorgarden. DIY Hoop House: A few materials used to build this: PVC plumbing pipe, fence posts, rebar and clear plastic. Nicely done, lots of pictures. From Old Windows: Recycle and reuse with this project, round up some old windows and make this clever structure. PVC Hoops: This can extend your warm- season gardening a month or more at both ends, and makes it possible for year- round gardeners to grow a wider variety of plants through the winter. Lumber & Plastic: Details aren’t thorough but enough to guide an experienced builder. Made with lumber and plastic. Storm Doors: Made with reused aluminum storm doors. Not very detailed instructions but might be enough for an experienced DIY- er to get the job done. Free Lean- To Plans: Details and diagram provided. Avoiding the Global Warming Impact of Insulation. Can insulation materials, which we use to save energy and help prevent climate change, cause greenhouse gas emissions? Yes, in two ways. First, it takes energy to produce and ship these materials—which we refer to as “embodied energy”—and using fossil fuels for these energy needs releases carbon dioxide (our most significant greenhouse gas). So in a sense, all insulation materials have embodied global warming potential (GWP). Second, two of our common insulation materials are made with hydrofluorocarbon (HFC) blowing agents that are very potent greenhouse gases. Extruded polystyrene (XPSExtruded polystyrene. Highly insulating, water- resistant rigid foam insulation that is widely used above and below grade, such as on exterior walls and underneath concrete floor slabs. In North America, XPS is made with ozone- depleting HCFC- 1. XPS has higher density and R- value and lower vapor permeability than EPS rigid insulation.), best known by the brands Dow Styrofoam (“blueboard”) and Owens Corning Foamular (“pinkboard”), insulates to R- 5 per inch and is made with HFC- 1. GWP of 1,4. 30—meaning that it’s 1,4. I have to note here that I’m not 1.
![]() This is a brief guide on how I took some old windows from houses they where tearing down in my neighborhood and turned them into a small greenhouse in my back yar. Can insulation materials, which we use to save energy and help prevent climate change, cause greenhouse gas emissions? Yes, in two ways. First, it takes energy to. XPS is made with HFC- 1. January 1, 2. 01. But various hints in technical literature have led. Light- emitting diode. Illumination technology that produces light by running electrical current through a semiconductor diode. LED lamps are much longer lasting and much more energy efficient than incandescent lamps; unlike fluorescent lamps, LED lamps do not contain mercury and can be readily dimmed. The other insulation material made with a high- GWP blowing agent is closed- cell spray polyurethane foam (SPF). This insulation material is sprayed into building cavities, onto a foundation walls, or onto roofs, and it insulates to about R- 6 per inch. Most, but not all, closed- cell SPF is made with HFC- 2. GWP of 1,0. 30. Some closed- cell SPF is water- blown, thus avoiding this concern, though the vast majority is HFC- blown. Open- cell (low- density) SPF, such as Icynene. Open- cell, low- density spray foam insulation that can be used in wall, floor, and roof assemblies. It has an R- value of about 3. GWP. Lifetime GWPA blowing agent with a high GWP is only problematic if that chemical leaks out over time and, unfortunately, not much is known about how quickly this occurs. Some researchers, such as L. D. Danny Harvey, Ph. D., of the University of Toronto (who first raised the concern about the high GWP of foam insulation materials in a technical article a few years ago), has assumed that a large majority of the blowing agent leaks out over time, but based on conversations with technical experts in the industry, our analysis in Environmental Building News adopts a more conservative assumption that only 5. When we combine these two sources (embodied GWP and GWP related to the blowing agent used) for an insulation material, we arrive at the “lifetime GWP” of these materials. For insulation materials made with HFC blowing agents, the vast majority of the total GWP comes from the blowing agent. See the table for the assumptions we used in the EBN article. Payback of lifetime GWPIf we then calculate how much energy a given amount of insulation will save over its life (which depends on where the house is located and how efficient the heating system is) we can calculate the “payback” of the lifetime GWP in the insulation. In other words, this is the length of time it will take for the energy savings from the insulation to pay back the greenhouse gas emissions that will result from the use of that insulation. With the help of John Straube and Daniel Bergey of Building Science Corporation in Westford, Massachusetts, we calculated the paybacks for adding different amounts of these insulation materials. This is reported in the June issue of Environmental Building News for those who want to see the analysis in more detail. We looked at adding R- 5 increments of insulation to a 2x. R- value. Measure of resistance to heat flow; the higher the R- value, the lower the heat loss. The inverse of U- factor. The energy model assumed the building is in a moderately cold Boston climate. This is shown in the two charts. The good news is that, except for XPS and HFC- blown SPF, the payback for the lifetime GWP of insulation materials is very low. If you add four inches of polyisocyanurate (R- 2. R- 3. 9 total) the lifetime GWP payback for that added polyiso insulation would only be 2. Even if you go all the way to a final R- 6. By comparison, if it’s XPS you’re adding to the 2x. Adding one inch of XPS has a 3. With two inches, the payback jumps to 4. To go all the way to a final R- value of R- 6. XPS) would have a payback of over 1. For SPF, the paybacks will be similar, though somewhat lower. Bottom Line – Avoid XPS and SPFSo what does all this mean? These differences are dramatic enough that, even if our assumptions are off by a significant factor, we can draw some general conclusions about sensible choices. If we’re building highly insulated buildings and doing so in part to mitigate global warming, we should use insulation materials other than XPS or SPF—at least until these insulation materials are produced with blowing agents that have far lower GWP. Low- GWP blowing agents, such as hydrofluoroolefins, HFOs, are likely to be available from Honeywell and Du. Pont in the next few years, though it is unknown how quickly XPS and SPF manufacturers could convert to these or other compounds.)There are lots of good alternatives. Now that polyisocyanurate (a common foil- faced rigid insulation material sold under such tradenames as Thermax, ACFoam, and Rmax) is made with pentane as a blowing agent, its GWP is very low (the GPW of pentane is about 7). Expanded polystyrene (EPSExpanded polystyrene. Type of rigid foam insulation that, unlike extruded polystyrene (XPS), does not contain ozone- depleting HCFCs. EPS frequently has a high recycled content. Its vapor permeability is higher and its R- value lower than XPS insulation. EPS insulation is classified by type: Type I is lowest in density and strength and Type X is highest. Open- cell SPF, such as Icynene, uses water as a blowing agent. Fiberglass, mineral wool, and cellulose do not use blowing agents at all. Note that XPS and closed- cell SPF offer some excellent performance properties (controlling moisture migration and airflow through the building envelope. Exterior components of a house that provide protection from colder (and warmer) outdoor temperatures and precipitation; includes the house foundation, framed exterior walls, roof or ceiling, and insulation, and air sealing materials.), so if we are substituting a different material, we have to address these building science issues carefully. The bottom line is that when we insulate our homes so that they will use less energy and thus help to mitigate climate change, we should be careful about which materials we use. Providing high levels of insulation with XPS or closed- cell SPF will counteract a lot of that well- meaning effort. To get a more complete understanding of this issue and for a checklist of alternatives to XPS and closed- cell SPF, check out the June, 2. Environmental Building News (to access this article, a log- in is required- -$1. I invite you to share comments on this blog. Will this information affect your choices of insulation materials? Alex Wilson is the executive editor of Environmental Building News and founder of Building. Green, LLC. To keep up with his latest articles and musings, you can sign up for his Twitter feeds.
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