In general, cantilevered steel beams are a nightmare. If part of the steel beam is in contact with exterior temperatures, then it's best if the interior portion of the steel beam is covered on all sides with insulation. This is generally impossible (because the interior portion of the cantilevered beam generally supports a load, meaning that you can't wrap the steel beam in insulation on all sides).
R-value is the term given to thermal resistance to heat flow. The higher the R-value of an insulation product, the more effective the insulation properties. Spray polyurethane foam comes in a range of densities and cel structure. Low density foams are referred to as Open Cel SPF while higher density foams are referred to as Closed Cel foam. 1.8-2 pound polyurethane foam has the highest R-value of readily available spray foam insulation used in homes and buildings.
Roof Spray Foam Insulation
Another thing we love about the Liquid Roof is its ability of not being damaged by freezing and other extreme temperatures. You will also appreciate its ability of staying flexible for a longer period of time. Did you know that it could also contract and expand as you roof moves? That is one of the things to look for when shopping around for this kind of product we found in the Liquid Roof.
Carefully examine the roof membrane (surface material) for cracks, tears, blisters, evidence of ponding, exposed foam, and open seams. If already coated, evaluate the condition of the coating. Pay particular attention to areas around roof penetrations (vents, skylights, pipes, etc), ponding areas, cracks in parapet walls, and the attachment of roof membranes to parapet walls. Roofs should be in good condition to warrant coating.
Porch urns are an excellent way to add seasonal curbside flair. However, tall items such as twigs, birch stems or even pumpkins can sway in the breeze and make a mess of your carefully planned decor. To prevent things from shifting, place your items in the container and spray around them with expanding foam to create a comfy nest that will keep your urns looking great. Place a layer of moss, hay or greenery on top to finish the look.
I've seen this only once, and it was with closed cell foam, but I've heard of it happening with open cell foam, too. I don't know the details, but I've heard it could result from a bad batch of chemicals, improper mixing, or too high a temperature. Whatever the cause, it's not a good thing. The photo below shows how the spray foam pulled away from the studs. A little bit of uninsulated area like that adds up to a lot of heat loss/gain when the whole house has that problem, as it did here.
Allison--would be very interested in your take on the GHG issues of foams, which have received lots of smart commentary recently. To highlight a few: architect Jesse Thompson's comments on Tom's Good vs Bad post on Energy Circle, the very thorough piece by Alex Wilson on Green Building Advisor and Michael Anschel's cautionary diatribe on Remodeling. http://www.youtube.com/watch?feature=youtube_gdata&v=ggLAUsiuI_o
Henry 587 Dura-Brite White Elastomeric Roof Coating is Henry 587 Dura-Brite White Elastomeric Roof Coating is a premium high solids formula offering better weather protection solar reflectivity and longevity than economy grade reflective roof coatings. Cured coating forms a permeable membrane which prevents liquid infiltration but allows moisture vapor to vent or breathe out of underlying substrate. Recommended ... More + Product Details Close
Most flat roofs are not perfectly sloped, causing water to puddle in some areas, in particular around the drains and scuppers. Many roof coatings are not rated or warranted for "ponding water", and thus might fail pre-maturely if exposed to standing water over long periods of time. Serious consideration should be given to the performance and limitations of the coating being selected. Some manufacturers will warranty their coatings including ponding water. Typically, manufacturers for acrylic roof coatings do not include warranties for ponding water, while some polyurethane and silicone roof coatings manufacturers will. https://youtube.com/watch?feature=youtube_gdata&v=ggLAUsiuI_o
If you're chemically sensitive, it's probably not a good idea to get it installed, but it's also not a good idea to breathe musty air from the crawl space either. In addition, your house and its contents are made of lots of materials that affect your indoor air quality. If you're really concerned about this, hire a company to test your air and tell you what you can do about it.
Find spray foam contractors, suppliers, equipment, news, and technical information about spray foam insulation, foam roofing, and protective coatings. If you are a homeowner, builder/architect, or interested to get into the spray foam business, we have set-up special areas just for you. Check out our information packed Spray Foam Guides to learn more.
Spray Foam Tanks
Most closed-cell spray foam is now formed using hydrofluorocarbon (HFC) blowing agents that have high global warming potential, partially or completely offsetting the climate benefits of the energy savings they can offer. In the United States, HFCs are scheduled to be phased out by January, 2021. A few spray foam suppliers have started supplying spray foam blown with hydrofluoroolefin (HFO) blowing agents without this problem as of early 2017.
Spray Foam Hot Roof
Apply coating when the roof is dry and the sealant has set. You will be using a 9-inch heavy-duty frame, ½-inch paint roller for spreading coating on roof or 1-1/4-inch roller for dipping in pail, and a 5–to-6-foot extension pole. Use a 3/4-inch roller with basecoats and emulsions. Map out your roof and make each pail fill that area. See Elastek Product Sheets for recommended coverage. An inexpensive 3-inch or 4-inch brush should be used to reach areas not possible with a roller. Use a stiff paintbrush for applying 103 Crack & Joint Sealant.
I don't know if it's common or uncommon, but installing a layer of rigid foam above your roof sheathing in order to interrupt thermal bridging is always a good idea, and is preferable in all respects to a roof assembly without any rigid foam above the sheathing. If you decide to install rigid foam above the roof sheathing, you shouldn't use closed-cell spray foam under the sheathing; either use open-cell spray foam (which is vapor-permeable) or a fluffy insulation like cellulose, mineral wool, or fiberglass (any of which will allow the roof sheathing to dry to the interior).
Low-density foam is applied as low or high-pressure, two-component polyurethane spray foam. Low-density spray foam can be applied on walls, in unvented attics, to ducts and ceilings, and in vented attics and crawl spaces. It is known as an air barrier, but permeable to vapor and moisture. It is often used to fill cavities in walls during construction.
Demilec, a company located in Texas, has invented a type of insulation foam that can help all of the cracks and uneven pavement problems. Geolift can help to lift existing concrete surfaces and fix those problem areas around your house with much less labor. Geolift works for driveways, sidewalks, patios, garage floors, even pool decks. And yes, it is a foam, just like your beloved spray foam! http://youtube.com/watch?v=ggLAUsiuI_o
Fill and seal expanding foam sealant is urethane Fill and seal expanding foam sealant is urethane foam designed to fill large areas quickly and permanently. Uses include filling holes cracks or gaps that require a complete airtight and waterproof seal but are too large to be filled with ordinary caulk. The foam expands approximately 3 times its original ... More + Product Details Close
Open-cell is also known as half-pound foam. It has an R-Value of 3.5-3.6 per inch, and its density is bout 0.5 pounds per cubic food. Low-density foams like these are made partially from raw biological materials Carbon dioxide or water is also used in the makeup. Open-cell uses far less material than closed-cell, but its R-Value is lower. Also, open cell requires a vapor retarder (like gypsum wallboard) and is riskier when used for roof sheathing. It's not highly recommended that you use open-cell insulation if you live in a cold climate unless you have that extra barrier. You should also compare how much money you spend versus how effective the open-cell insulation is wherever it's installed.
Thank you, Allison. We have a split system unit (actually 5) with the heat being propane. The foam guy said that it needed ventilation, so completely sealing the attic wouldn't be a good idea. It sounds like you are saying that the systems need to be vented out of the attic or replaced with some type of closed system. But I shouldn't bother spraying if the plan is to leave the soffet vents open. Is that correct?
Demilec, a company located in Texas, has invented a type of insulation foam that can help all of the cracks and uneven pavement problems. Geolift can help to lift existing concrete surfaces and fix those problem areas around your house with much less labor. Geolift works for driveways, sidewalks, patios, garage floors, even pool decks. And yes, it is a foam, just like your beloved spray foam!
Warning: EnergyGuard™ Elastomeric Roof Coatings can freeze below 32° F. This is because the product is water based. In case of freezing temperatures, stop the application process. After application, you must allow the product time to dry before exposing the elastomeric roof coating to foot traffic or water. You should also cover the containers and dispose them responsibly after application. In case you or someone else i.e. a child ingests the coating seek immediate medical attention. Don't induce vomiting. https://www.youtube.com/embed/ggLAUsiuI_o
In addition, it's difficult for an inexperienced installer to evenly spread the insulation foam over a surface. Miissing spots can leave holes and gaps for cold air to get through. Proceed with this project yourself only if you're doing a small insulation project -- such as installing foam in a crawl space or around your plumbing. Leave larger projects like the attic, basement or garage to the professional insulation contractors. Insulation professionals have the tools, equipment and background knowledge necessary. Moreover, they know how to accurately price insulation, whereas you could inaccurately budget for a DIY project and end up paying significantly more. Don't take the medical, physical or financial risks that come with pursuing this as a DIY project unless you're absolutely certain you have the skills. https://youtube.com/v/ggLAUsiuI_o
I am an Architect in Toronto. I am designing a new roof addition to a row house building. Because of existing conditions and the shape of the new roof. It may be easiest to use closed cell spray foam within the areas of the joists. My question is when spray foam is used in this situation do I need to worry about how the joist members may be thermal bridges? It is not common to provide a little bit of rigid insulation to protect the joist members? The additional layer of outboard insulation will require an extra layer of plywood above the insulation which will add to cost.