Spray foam insulation is by far the best for an attic. It is sprayed in the rafters areas and basically seals off the entire attic and stops the heat as soon as it enters from the roof. It can be very expensive though compared to regular fiberglass insulation or blow in insulation.
The best thing you could do for your home to keep the warm in and the cold out is to 1st. check your insulation in your attic if your not properly insulated the heat will escape. Another is making sure your windows are secured and latched. and proper weather seal is on your doors so draft cannot come in.
We've done this application numerous times in southeastern PA with one subtle change, we use closed cell foam insulation directly against the underside of the roof sheathing. Open cell will continue to let air/humidity through, closed cell will not. Since air can't move through the closed cell foam there isn't any need for air flow under the roof sheathing because there won't be any humidity there to potentially condensate. Air already moves through the fiberglass insulation and that won't change when the Attic becomes conditioned space. I believe it would be best to remove ALL of the existing fiberglass ceiling insulation so that the Attic space becomes 'one' with the rest of the House. Fresh air intake to the fossil fuel furnace is necessary. It should be set up with a power damper that opens when the furnace turns on to allow combustion air directly to the heat chamber. When the furnace isn't running the damper is closed to keep unconditioned air out of the Attic.
Dennis D. Gehman, CR, MSA, CLC, CKBR, GAC, CAPS
President
Gehman Design Remodeling
NARI = National Association of the Remodeling Industry
CR = NARI Certified Remodeler
MSA = CertainTeed Master Shingle Applicator
CLC = NARI Certifled Lead Carpenter
CKBR = NARI Certified Kitchen & Bath Remodeler
GAC = Green Advantage Certified
CAPS = Certified Aging in Place Specialist
The best move would be to simply make sure the existing vapor barrier product is installed properly (flush to ceiling below) and add blown insulation over top to to get the best R value and at the least expense.
Hello John,
STEP 1. This is a very common for homes with room(s) obove a garage. Replacing the window (s) in the bedroom may not solve your entire problem if the glass package you select does not include a high performance heat reflectant type glass. Which ever manufacturer you decide, its best to pay the additional cost and upgrade to thier best performance glass. If you have already invested in new windows then check your paperwork to see if there is a greater performance glass option you can upgrade with for that type window . This is a simple process and can greatly reduce your Solar Heat Gain for minimal investment.
STEP 2. Select a certified insulation professional in your area to provide you with a "critical point air seal". Properly applied by a certified professional at upper and lower rim joists in this room aproximatly 1' in width by 2" in thickness. Air sealing the upper and lower rim is a minimal investment and provides a significant and noticable change in comfort with a quick ROI. Consider this service for the entire home.
Warm regards
Colorado Home Exterior
Windows and doors are the largest culprit in lost of energy efficiency. It may not be the cheapest option but will provide you with the largest impact.
Adding insulationis only one piece of the puzzle. The object is to keep the attic space roughly the same temperature as the ambient outside air. This is accomplished via insulating the building envelope to keep your heat IN the building, AND proper ventilation of the attic space to move air around and through the attic. Adding insulation can help with the former, while making surte tha you have proper ventilation is also key. In many cases, the design of the roof or the environment the home is in isn't conducive to these static techniques and ice will form anyway. In those cases, we've had 100% success with properly installing ice melt systems along those sections of roof and gutter to allow water to work its way down through the gutters and downspouts and not build up behind an ice dam. See in the pic the area with the cables, and to the right the area without (which we've since added!) Good luck!
Foil backed plywood is the more efficient than spray. Here is one site but many use the same figures. http://www.atticfoil.com/install-questions/paint-vs-foil.html
Depending on what year your house was built, you might have asbestos in that popcorn ceiling. Typically, anything older than 1979 is a good chance that it could have asbestos; our company regularly finds that with popcorn ceilings. We always send a environmental hygenist out to our jobs to confirm whether or not a house is "hot" for asbestos. It's preventative protection for our workers.
Removing popcorn ceilings requires a lot of preparation to prevent contamination of the other areas of your home. You will need to cordon off the area (room) with some kind of plastic covering the walls, floor, and entry area - this is for your own protection. Also, you will need to wear personal protective equipment including a tyvex type of suit that covers you from head to toe, gloves, safety glasses, and most importantly - a respirator. These things are necessary to keep you safe from breathing in the microscopic fibers of asbestos and preventing you from getting asbestosis or mesothelioma (a tumor of the mesothelium, often malignant and thought to be caused most commonly by the inhalation of asbestos particles.)
Christofer, There is a lot written about your particular condition. What I would do would be to install a spray polyurethane insulation (closed cell insulation) into the attic ceiling and down to and including the eaves. this installed over a 1/4" plywood that would be "cleated" down at a minimum of 1" below the bottom of the roof sheathing, thus eliminating the "hot roof" situation. As far as moisture... if you understand that warm air rises and carries the moisture up (another reason i would use a closed cell product) then it makes sense to foam any walls or kneewalls as well. The venting on the top side would not be to eliminate any interior moisture, but to make your shingles last longer (keep them from overheating). Quite a few asphalt companies have disclaimers on warrantees because of this issue. You would need to check with your steel roof manufacturer how they respond to a hot roof application.
Ok so you don't really want all that moisture collecting on your windows and or finished wall substrates in the attic. So an ERV/HRV or even the furnace fan run continuously would help distrubute or evacute the excess moisture if this is your main house furnace (air handler). FYI- change filters monthly in these systems to help mitigate possible mold issues. I recommend the 6" combustion air (bringing in dry outside air) code required in IRC. I am not sure if this furnace unit in your attic is the primary furnace (air handler) for the home. If so that would help distribute attic moisture to the lower parts of the home. If separate attic unit only, I'm not thinking it will ever distribute moist warm air to the lower level like you suggest.
Remember this... once you start changing the function of your home's ventilation/conditioned or unconditioning of a space you will be changing the whole dynamics of how the house used to function. Henceforth do your homework. All this said...I run my company business in the extreme temperature zone of Minnesota. Your local heating guys should have a better handle on providing a safe living environment for your family. Mold can be a serious issue.
John,
If it is a small repair, you may want to test out a product at Lowes. Homax ceiling texture. I'd suggest trying it on a scrap piece of drywall (make sure it's at ceiling height for testing). Jayme and Phillip both had great ideas. Perhaps yet another would be to just remove the popcorn all together.
As previous answers point to adding proper insulation in the attic, it is also recommended that using a leak barrier under the roof shingles from the eave of the roof back until you reach 24 inches above an interior wall. In other words, the leak barrier, a rubber like membrane that adheres to the roof deck, will cover the overhang and at least 24 inches above the interior wall of the house around the perimeter. This membrane helps prevent water from melting ice dams from entering the home and overhang (soffit). Its rubber like properties help seal around the nails that are driven through it that hold the shingles on. If your roof does not currently have a leak barrier, the existing shingles will have to be removed and replaced where the leak barrier is to be installed. A couple of recommended leak barrier products from GAF are WeatherWatch and StormGuard.
Here is a fairly good article on the subjecct.
"Radiant barrier spray-on paint is essentially liquid foil. While not all radiant barrier paints are the same, basically they are made by grinding pure aluminum into a fine powder and then mixing it into clear paint. Once the clear paint dries the aluminum powder forms a layer of aluminum.
The best radiant barrier spray spray is only available to commercial contractors, and is an environmentally safe, water-based low-e paint called HeatBloc-75, Radiance e.25 or Lo/MIT. When the paint is installed correctly, it will reflect about 75% of the radiant heat and can be a very good product.
Getting good results with radiant barrier paint assumes a couple of things:
The rafters are being sprayed completely (this usually costs more when you get an estimate).
The paint is being applied with the correct coverage (many contractors put it on either too thin or too thick).
The paint is not diluted. There are some contractors (even large ones who advertise heavily) that will cut* the paint with water in order to extend the coverage. *Cutting is when water is added to paint; it is cheating to cut costs.
As a result, the true effectiveness of radiant barrier paint installed by many contractors is really only about 15-40% reflectivity. The typical consumer can’t tell the difference between a good installation and a poor job without testing.
Radiant barrier paint spray is not a good Do It Yourself (DIY) project. The fumes are noxious, you must use a VOC respirator, a high-end airless spray rig, the proper size spray tip, and the proper pressure to get correct coverage and eliminate clogging. Forget about painting with a roller because it is impossible since there are thousands of nails sticking through the roof deck; additionally, using a paint brush to manually paint it on would take forever. Most people who try to do it themselves will actually blow too much paint and the material cost alone will be over $0.30/ft. With the cost of radiant barrier foil only being less than $0.13/ft, it’s obvious it is not only a better product, but a better deal.
Different Brands of Paint & Testing Results
reflective coatings comparisons chartMany companies have developed radiant barrier spray paint. In fact, none are true radiant barriers since they all reflect less than 90% of the heat which is the definition of a true radiant barrier; technically they are reflective coatings. Below is a chart with some test results by RIMA (Reflective Insulation Manufacturers Association) which did independent testing on all the different radiant barrier paints.
Notice that the best paint still emits 22% of the radiant heat, compared to only 3% for radiant barrier foil. Some paints claim to be award winning, although what award they are receiving still remains to be identified or significant.
Additionally, the paint tests were conducted on perfectly smooth samples, applied under laboratory conditions; these conditions are different than your attic. Your attic is made up of porous wood that loves to soak up paint instead of keeping it on the surface to create a smooth, shiny film, which would be required to be fully effective. In order for paint to come close to the tested emissivity rating, the wood surface must be primed with a primer/base coat of paint first.
Why You Should Use Radiant Barrier Foil
The main reason you should consider the foil over the paint is because with the paint you are basically counting on the product to deliver results, while with the foil you are simply needing the person (which may be yourself) to get the installation done. So long as the foil is installed somewhere between the roof/rafters and the insulation, it will reflect 97% of the radiant heat.
This is indisputable; radiant barrier foil works!
Furthermore, it is actually difficult to install the foil wrong. This is the main difference between Quality Assurance and Quality Control. You can assure that reflective foil will work; while you can only hope that the reflective coating is installed correctly. We do not sell or install radiant barrier paint; we only sell radiant barrier reflective foil insulation because it is the best.
The problem occurs when reflective paint is put on too thin or when water is added to the paint/an inferior cheap paint is used. Then what? Then the customers do not get the results or the cool attic they are promised.
To offset this disappointment, some companies have resorted to doing things like giving away free solar fans. Sure, if you put an attic fan in the attic it will decrease the attic temperature and could even get it close to outside temperature; however, it doesn’t matter what kind of fan it is, a fan will not stop any radiant heat transfer. A cooler attic is nice, but what we really need to do is reduce the temperature of the insulation. For more information, read our article about air temperatures versus surface temperatures and how they affect your home.
