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June 30, 2008

Question: What’s the difference between ProPink® and FOAMULAR® rigid insulations?

Tom writes from Ashland, Massachusetts: "First, what's the difference between ProPink and FoamulaR rigid insulations? Second, I have searched and found contradicting replies from this blog on installing rigid foam insulation on the exterior of a home that has interior fiberglass batts with a vapor barrier. Since the perm rating of your rigid insul is 1.1 it is practically a vapor barrier. Now if the rigid insul is installed on a home with an interior vapor barrier then does that not sandwich the walls between the 2 barriers? Could this 2 barrier system lead to problems with trapped moisture? I always thought Your Fan Fold insul was perforated with holes to solve the above mentioned problem. Through the tiny holes punched in the rigid insul water vapor would escape and yet most heat would be trapped."

Answer: PROPINK® insulating sheathing has a film facing. It is a FOAMULAR® brand insulating product that is made with extruded polystyrene. The facing is the key difference in the PROPINK product and standard FOAMULAR insulation. FOAMULAR is not a vapor retarder or barrier. So we recommend using it as an exterior insulation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 11:20 AM | | TrackBacks (0)

Question: What can I use to insulate my attic?

Joe writes again from Cleveland, Ohio: "I have an attic with a floor which is only used for storage. The joists are 2x6s. What can I use to insulate my attic; whether removing the boards or blowing in insulation. I recently purchased r30 backed sheets from a supplier. I want to know if these will do the job or am I wasting money because I don't have 9 inches of space to get the full r value."

Answer: Adding insulation will help. But adding R-30 to a 2x6 cavity will reduce the R-value to 18. The use of blown-in Fiberglas™ insulation will result in similar R-values.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 11:18 AM | | TrackBacks (0)

Question: Does the old wiring pose a fire hazard with insulation?

Joe writes from Cleveland, Ohio: "I have a ranch which was built in 1950. I recently discovered there was only a tin foil lining in the attic under the floor boards. The foil is all the insulation I have in the attic. We do use some of the space for storage so we would like to keep the floor in the attic. I also have old knob wiring which are on the 2x6's under the floor. What product would best fit my needs? Can I get good insulation with just 6 in. of room? And does the old wiring pose a fire hazard with that type of insulation?"

Answer: For a 2x6 cavity you can get R-19 or R-21. If you are keeping the foil in place, use unfaced Fiberglas™ insulation. If you are removing the foil, use Kraft-faced Fiberglas insulation.

Knob and tube wiring should be kept at least three inches away from the insulation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 11:14 AM | | TrackBacks (0)

June 27, 2008

Question: How should I insulate an unheated tool shed?

Frank writes from Smyrna, Georgia: "I am installing a 10X10 tool shed in a wooded part of the yard and want to add insulation and drywall for a finished look. Because of the location I have concerns of mildew and mold, as well as the heat and cold. Most of the frame is built with the studs 24 inches apart except around a window, and have concerns about special precautions that may be needed there as well. Since the shed will not be heated, should the paper face the exterior, or the interior where the drywall will be placed? What would you suggest for the vaulted ceiling?"

Answer: This is a tricky question to answer since you don't need to insulate an unconditioned space. Insulation is intended to slow the movement of heat from one side of a wall or ceiling to the other side, and since your shed will not be heated, the inside and outside temperatures should be similar. Insulation may slow the buildup of heat in the shed during hot summer days but it will also slow the dissipation of that heat in the evening. The paper facing is commonly installed toward the warm-in-winter side of the wall or ceiling.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 03:40 PM | | TrackBacks (0)

Question: What is the difference in two products labeled R-13?

Rick writes from Franklin, Indiana: "When I go to my local home improvement store I see R13 batt insulation and R13 rolled insulation that is labeled "Utility". The batts are recommended for walls and crawl spaces but the rolled doesn't say anything about walls and just says around doors, basement etc. What is the difference? Isn't R13 R13?"

Answer: You are correct - R-13 is R-13. For some projects it may be easier to work with batts than rolls, and vice versa. Some projects need a vapor retarder and others do not. Be sure to get Kraft-faced product if you are insulating exterior walls. The paper is installed toward the warm-in- winter side of the wall.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 03:36 PM | | TrackBacks (0)

Question: Is there an alternative insulation for my project?

Jon writes again from Saint Paul, Minnesota: "I am well aware of fiberglass. I was inquiring about alternatives."

Answer: Owens Corning manufactures two types of insulation - fiberglass and extruded foam. FOAMULAR® insulation has an R-value of five per inch but is not best suited for your application. I am not aware of a suitable alternative.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 03:33 PM | | TrackBacks (0)

June 26, 2008

Question: Can I use insulation over knob-and-tube wiring?

Gary writes from North Augusta, South Carolina: "Can I use your batt insulation in my attic over knob-and-tube wiring if I lay the batts perpendicular to the joists so it doesn't come in contact with the wires?"

Answer: Knob and tube wiring should be kept a minimum of 3 inches away from Fiberglas™ insulation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 04:51 PM | | TrackBacks (0)

Question: Should I insulate the garage's exterior walls if I have a bedroom over the garage?

Jacob writes from Kernersville, North Carolina: "Should I insulate my garage's exterior walls if I have a bedroom over my garage? It seems my son's room (2nd floor over garage) is cooler than other parts of the house. I am sure this is because heat rises and the room below is not heated. Every wall/ceiling in the garage that is connected to the house is insulated. I have one and half walls in my garage that are not insulated. Would it help make my sons room warmer if I would insulate my non-heated garage?"

Answer: The best thing to do is build up the insulation around the cold bedroom. Insulating the ceiling of the garage, or improving what is there, should help. But insulating the exterior walls of an unheated garage will not.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 04:49 PM | | TrackBacks (0)

Question: When attic flooring compresses insulation, does is significantly decrease R-Value?

Stephan writes from Abingdon, Maryland: "When attic flooring is installed and compresses loose fill insulation, does is significantly decrease the R-Value?"

Answer: Fiber glass insulation works on the principle of trapped air pockets. By compressing fiber glass insulation, you decrease the amount of air trapped in the material. For example, compressing R-19 into a 2x4 wall will give you an R-13 value. If you click through to the chart you will see what that it is for insulation compressed in a wall cavity but the same principle applies for attic insulation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 04:44 PM | | TrackBacks (0)

June 25, 2008

Question: How much does it cost to add insulation?

Nik writes from Swedesboro, New Jersey: "How much does it cost to add extra insulation. I have a 3400 Sq ft two story home and have R-30 insulation in the attic. I am thinking of adding another R-19 to make the attic R-49 complaint. How much would a roll of R-19 pink insulation cost and how much area does a roll cover? Or give me some estimates on the per-square-foot costs."

Answer: Owens Corning manufactures PINK Fiberglas™ insulation but the company does not set retail pricing. Retail prices are set by the stores that sell the products to contractors and consumers. If you are looking to upgrade the insulation in your home’s attic, you should be able to get the product you need for a few hundred dollars.

To find an Owens Corning insulation retailer based on you ZIP Code, go to the company’s home page and select Owens Corning Building Materials and Services. Click on the button labeled Find a Building Professional. Enter your ZIP Code and select the words that best describe your project. Another click or so and you will have the option of selecting retailers or contractors. Click here for a shortcut to the Locator page.

There is also information on the website about R-19 PINK Fiberglas insulation. Click here for a shortcut to that page.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 07:40 PM | | TrackBacks (0)

Question: Which side should the vapor retarder be on?

Mark writes from Scarborough, Maine: "I have already purchased r30 faced insulation for my garage ceiling. Above the garage is a heated bonus room 65 deg. I plan on heating the garage at min temp around 40ish to keep pipes from freezing, which way should the paper barrier be, or does it matter with both spaced heated?"

Answer: We recommend the paper facing be installed toward the area that will be 65 degrees.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 07:38 PM | | TrackBacks (0)

Question: Is there a better way to insulate my finished basement walls?

Matt writes from Troy, Ohio: "I am finishing my basement walls and have applied slotted 1 1/2 inch foam board insulation with 1x3 furring strips that are flush with the foam. I want to install drywall on the upper half of the wall and the bottom 4 feet with tongue and groove pine boards. I know I need a 15 min. fire covering but wanted to but the pine flush with the drywall. I have already added the fan fold thin insulation on the top half and after putting 1/2 inch drywall over that it will be flush with the thickness of the pine. I thought about using a foil behind the wood which is a good fire rating, but don’t want to cause condensation or wanted to know if there is a better way. I'm racking my head over this. Thanks for any suggestions."

Answer: We recommend contacting your local building inspector to find out if what you have will meet the requirements of a 15-minute thermal barrier. The covering doesn't need to be fire proof so the use of foil over the FOAMULAR® insulation is not necessary.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 07:34 PM | | TrackBacks (0)

June 24, 2008

Question: What insulation goes above a suspended ceiling?

Steve writes from De Armanville, Alabama: "What type of insulation goes above a suspended ceiling?"

Answer: This will depend on what is above the suspended ceiling but unfaced Fiberglas™ insulation is commonly used above a suspended ceiling.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:35 PM | | TrackBacks (0)

Question: What type of insulation would you suggest over cellulose?

Rob writes from Youngstown, Ohio: "My house was built in 1948. I went up the attic to check out my insulation, and it appears there was a very thin yellow, paper faced insulation batts between the joists - paper side down. When the roof was re-shingled by the previous owners 6 years ago, cellulose blown-in was placed over the batts. I was considering adding more insulation now since the tops of the joists are visible again. What type of insulation would you suggest over cellulose? Unfaced rolled bats perpendicular to the joists, or blown in propink fiberglass?”

Answer: We recommend unfaced fiberglass batts be placed perpendicular to the joists. ProPink® blowing wool can be used but that product requires a special blowing machine to install it.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:32 PM | | TrackBacks (0)

Question: Is there a significant difference in heat absorption between light and dark roof colors?

Ruth writes from Davis, California: "Is there a significant difference in heat absorption between light and dark roof colors? If I am looking at Oakridge Pro shingles; will the material absorb heat even if it is light colored?"

Answer: The surface reflectance of asphalt shingles could range from 4 to 26 percent based on the color of the shingle. And yes, even the lightest and brightest colors of roofing materials absorb heat. If your real concern is saving energy and reducing the cost of cooling your home, there are other factors to be considered as well, such as ventilation and insulation. Attic and/or roof deck ventilation are an important factor in reducing heat buildup in the attic. For an unconditioned attic, air should be able to move freely through the space from the soffit to the ridge of the roof. If there is conditioned living space in the attic there should be a minimum of one inch of space under the roof deck and ventilation that flows in through the soffit and out through the ridge.

There is information on the Owens Corning website about ventilation. The minimum ratio is 1/300, meaning one square foot of ventilation for every 300 square feet of attic space when you have the proper balance of ridge and soffit/eave vents.

Whatever heat does enter the attic can be kept out of your conditioned living space by insulation. The more insulation you install, the greater the R-value and the better it will work at slowing the movement of heat into the home.

Bottom line: To make your home energy efficient, consider all of the components of the system as a whole. If you prefer to use a darker shingle for aesthetic reasons, compensate with more ventilation and insulation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:28 PM | | TrackBacks (0)

June 23, 2008

Question: What insulation should I use in the garage ceiling?

Margaret writes from Waldwick, New Jersey: "My house is 50 years old and I don't believe the ceiling in the garage is insulated at all. Therefore, the bedrooms above are always about 8/10 degrees cooler than the rest of the house. The ceiling is sheet rock. What type of insulation would be best suited to remedy this situation?"

Answer: We recommend Kraft-faced R-25 Fiberglas™ batt insulation with the vapor retarder installed up toward the warm-in-winter side. However, this will require the sheetrock be removed for the installation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:16 PM | | TrackBacks (0)

Question: What can I put over the fiberglass to hold it in place?

Steve writes from Shelburne, Vermont: "I have 2x4 walls with fiberglass batts and an attic with fiberglass batts between the floor joists. Can I blow cementitious or isocyanurate foam into the walls or onto the attic floors without removing the batting? I'm trying to accomplish 2 things: increase insulation value, and bind the fiberglass so that it can no longer float free in the air (there is a fair amount of exposed fiberglass and I have respiratory issues). If not, anything else I can put over the fiberglass in attic to hold it in place - without adding a vapor barrier to the wrong side?"

Answer: You can install anything breathable over the blown in to hold it in place. Owens Corning hasn't tested its fiberglass insulation with other binding products. I recommend contacting the manufacturer of such products to see if they have done any testing.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:13 PM | | TrackBacks (0)

Question: Should I install a rafter vent between every rafter or only where there is a soffit vent?

Andrew writes from Whitmore Lake, Michigan: "We are building a small (900 sq ft) cabin in Northern Michigan. The cabin has a ridge vent and six soffit vents on each side. The cabin has scissor trusses to give us a raised ceiling. I am preparing to install the ceiling insulation, but was wondering if I should install a rafter vent between every rafter or only where there is a soffit vent?"

Answer: Installing rafter vents where there is a soffit vent should be sufficient, providing there are enough for adequate ventilation.

There is information on the Owens Corning website about installing raft-R-mate® attic rafter vents. You can also find information online about ventilation. The minimum ratio is 1/300, meaning one square foot of ventilation for every 300 square feet of attic space. We recommend a ratio of 1/150.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:08 PM | | TrackBacks (0)

June 21, 2008

Question: What type of insulation should we use for an inside room in the basement?

Lori writes from Hornell, New York: "We are insulating an inside room of a basement. Which type of insulation should we use to cover the studs which we will then cover with sheet rock? The room in not heated, but the cellar is."

Answer: Interior walls are usually insulated for acoustic purposes to reduce sound transmission from one side of the wall to the other. For this purpose we generally recommend filling the stud cavity with fiberglass insulation and not covering the studs with anything other than the sheet rock or similar wall board. Because the entire basement is heated, there should be little or no thermal movement between the new room and the conditioned space surrounding it. Clicking on the highlighted words in this sentence will take you to the Owens Corning Web page presenting QuietZone® noise control solutions for the home. The products in this section are specifically designed for noise control. You will need to check with local building materials retailers for availability.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 03:55 PM | | TrackBacks (0)

Question: Should I put fiberglass insulation in the walls?

Nick writes from Erie, Pennsylvania: "I glued 3/4 foamular insulation to block cement walls in my basement. I have a 3 inch air space then built 2x4 walls which will be covered with sheet rock. My question is: Should I put fiberglass insulation in the 2x4 walls and if so should it be faced or unfaced? Is the foamular a vapor barrier? If I put insulation in the walls will I create a double vapor barrier? Or should I just use the foamular with no fiberglass insulation?"

Answer: My friends at Owens Corning do not recommend using Fiberglas directly over FOAMULAR® insulation in a basement. And the FOAMULAR should be covered with a 15-minute thermal barrier such as sheetrock. Then you are done. FOAMULAR is not a vapor retarder.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 03:50 PM | | TrackBacks (0)

Question: Can I sufficiently insulate the ceiling or do I need more depth?

Tim writes from Smyrna, Tennessee: "My house is twenty years old and for some reason the builders used 2x6 rafters for the cathedral ceiling. The space above the garage is used for storage and I plan to finish the room and use it at living space. The floor has 10" joists that have not been insulated. I plan to blow insulation into the floor as it is covered with plywood and fur out the ceiling rafters for a total of 8 inches of depth and use the attic rafter vents for ventilation. Can I sufficiently insulate the ceiling or do I need more depth? What insulation should I use for the ceiling and floor? And should I use the rafter vents in every run or should I do every other one?"

Answer: The recommended R-value for your Zip Code area is R-38. A fiberglass batt of R 38 is 12" thick. You can get R-25 for the 2x8. With about four inches of blown-in insulation you should meet the requirement. You should install Raft-R-Mate® attic rafter vents in every cavity that currently has ventilation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 03:48 PM | | TrackBacks (0)

Question: Once I add insulation, can I put wood over it?

Frank writes from Colonia, New Jersey: "The attic over our bedrooms get extremely hot. It has pull down stairs and plywood laid on top of the beams which we use for storage. I want to add more insulation. Once I add the insulation, can I put the wood back over it?"

Answer: You can place the wood back over top of the insulation provided that the insulation will not be compressed as a result.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 03:45 PM | | TrackBacks (0)

June 20, 2008

Question: How much clearance should I leave between the top of the insulation and the bottom of the rafters?

Dan writes from Nashua, New Hampshire: "I am planning to install additional loose fill insulation in my attic using the Owens Corning AttiCat system. There is already 6 inches of fiberglass loose fill insulation between the 2x6 floor joists in the attic (no floor covering over the joists). When looking at the minimum square footage of vents required per square foot of attic space, I have plenty of ventilation (one gable vent on each end of the attic, plus eave vents along one side of the attic). However, the attic only has approximately 3.5 to 4 feet of clearance from the top of the joists to the peak of the attic). How much clearance should I leave between the top of the insulation and the bottom of the rafters?"

Answer: You have plenty of space for ventilation. A minimum of 1 inch should be left to maintain soffit and roof deck ventilation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 04:11 PM | | TrackBacks (0)

Question: Should I remove the old blown-in insulation?

Pat writes from Saint Louis, Missouri: "I have blown-in insulation in the attic of my 65 year old house. It is at least 15 years old and has been walked over by several workmen and has become compressed. I want to increase the insulation in the attic to stabilize the temp on the second floor of my brick home. Should I vacuum out and remove all the old blown-in insulation and then install unfaced rolled insulation between the ceiling joists? Then add a second layer of rolled insulation on top of and perpendicular to the joists? Or is it better to leave the old blown-in stuff alone and just add an attic blanket over that, even if if has been compressed? I don't want to try to blow in more insulation myself. Rolls are much easier and cleaner to work with. I want to shoot for an R Value of about 49 total, correct for the St. Louis Area? Please help!!"

Answer: I don't recommend removing the existing insulation. It is usually better to leave it in place to avoid the work and mess, keep the old insulation out of the landfill and take advantage of whatever R-value it is able to contribute. Rolling the new insulation on top of the existing insulation is fine; fill the cavity between the joists first and then run the next layer perpendicular to the first.

If you do decide to remove the existing insulation, the first layer you install between the joists should be faced and the facing should be down toward the warm-in-winter side. Your target total of R-49 is what is recommended for your area by the U.S. Department of Energy.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 04:07 PM | | TrackBacks (0)

June 19, 2008

Question: Is it OK to use polystyrene on the interior of exterior walls underneath the sheetrock?

Mike writes from Frenchtown, New Jersey: "I am considering building a new home in central MA. Several years ago I lived in Rochester, NY where a builder was using polystyrene on the interior of exterior walls underneath the sheetrock. The builder claimed this method, using 2x4 construction, provided an R rating equivalent to 2x6 construction. I have been researching and trying to find information on this method but all I can find is applying the polystyrene to the outside of the exterior wall. Is applying polystyrene to the interior of an exterior wall an acceptable method, are there any concerns regarding moisture buildup and where can I find information on the method and materials?"

Answer: The builder is correct. This has become a standard building practice in recent years to improve R-value in 2x4 exterior walls. If done properly using unfaced Fiberglass insulation, moisture should not be a concern. Owens Corning does not have literature showing this application but our technical service department can discuss it with you. You can reach them through 1-800-Get Pink™ (438-7465).

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Question: Should I wrap the interior with plastic to make a barrier?

Ron writes from Coquille, Oregon: "I am confused with the contradictory terms 'vapor barrier' and 'vapor retarder'. If the insulation has a barrier, I assume I need a permeable exterior wrap. If it's a retarded, I would assume I need a barrier (non-permeable) exterior wrap.

I am under the impression that a 'plane' of a wall must be chosen for a 'barrier' (either the exterior or the interior). It makes sense to use the interior plane the barrier. If it's just a retarder on the insulation, should I wrap the interior with a 'plastic visqueen' to make it a barrier? I like short, succinct questions!!!"

Answer: The Kraft paper on our insulation is classified as a 1.0 perm vapor retarder. It is acceptable for wood frame applications. It is NOT necessary to install an additional barrier. The paper is typically installed toward the sheetrock side of the wall. I hope that helps.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:10 PM | | TrackBacks (0)

Question: How much room do I need to leave for soffit vents?

Mike writes from Woodridge, Illinois: "I have blown-in insulation in my 800 sq/ft attic. I was getting some moisture in the attic, and installed two bath fans in the showers upstairs which vent out of the roof, and also installed an attic fan to help airflow. I have soffit vents, 6 total, and they are not blocked. I believe this will cure my moisture problem, am I on the right track?

The blown-in insulation just barely fills in the space between the joists and a home inspector said it is about an R-13 or R-15 value. I plan on adding unfaced R-30 over the existing insulation, across the joists. How much room do I need to leave around the edges for the soffit vents? Inches? Feet?"

Answer: You are on the right track! A minimum 1 inch should be left to maintain soffit ventilation.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:07 PM | | TrackBacks (0)

Question: Can I purchase a spray on vapor barrier?

K writes from Larwill, Indiana: "Last weekend I put up half of the drywall on my garage ceiling. I forgot to put up a vapor barrier and DO NOT want to break my back taking down the drywall that I just put up to put on the barrier plastic. What else can I do? Can I purchase a spray on vapor barrier? If so, then where? Lowe's? Menards?"

Answer: Yes, you can apply a "spray on" or "paint on" vapor retarder to the ceiling in the garage. I don't know what paints they have at the stores you mention but the product can be found at most paint shops.

You don't mention it but I am assuming you also installed insulation and that the garage space is conditioned. If the garage and the space above are not conditioned, you don't need insulation or a vapor retarder. If the space above the garage is conditioned, painting the ceiling with a vapor retarder will put it on the wrong side of the assembly. In that case I would either paint the flooring above, if that is possible, or leave it alone because the movement of moisture down through the assembly should be minimal.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:01 PM | | TrackBacks (0)

June 18, 2008

Question: Where should I place the insulation?

Joe writes from Fisherville, Kentucky: "I am building a house and the garage has a bonus room above it. I plan on installing Faced R30 insulation in this location but my ceiling joists/ rafters (trusses) are about 16 inches tall. Should I place the insulation at the bottom or top of the this space, considering that I will have about 7+ inches of void between the bonus floor and garage sheetrock ceiling."

Answer: The paper should be in contact with the bonus room floor.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 05:53 PM | | TrackBacks (0)

Question: Do I need to install a vapor barrier?

Will writes from Urbana, Iowa: "If I am adding rigid foam insulation to my basement wall do I need to install a vapor barrier?"

Answer: We don't recommend adding a vapor retarder to FOAMULAR® insulation used in basement walls. We do recommend checking with local building code to see what is permitted and/or required.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 05:49 PM | | TrackBacks (0)

June 16, 2008

Question: Can I remove the insulation on my own or have it done professionally?

Lori writes from Liverpool, New York: "There is pink insulation between the floor joists on the 'ceiling' of my crawl space. The insulation is very old and had long been a nesting site for mice, so it is full of mouse feces and urine. We have closed up holes to the varmints but the insulation smells and I want to remove it from my home. Can I do that on my own with a mask and eye wear and long sleeves/pants etc., or do I have to hire a contractor. If the latter, how do I find someone who will do the job properly."

Answer: There is no long term health risk in the situation you describe. There is a possibility of irritation if the insulation is handled. That irritation is a mechanical abrasion caused by the ends of the fibers scratching the skin. This is not an allergic reaction and the itching generally subsides when the source of the irritation is removed by washing it off.

When you remove it, my suggestion is to bag it to minimize contact. Take your time and work "gently" to minimize dust. To minimize the temporary skin irritation associated with fiberglass insulation, take the precautions you mention - wear a long sleeved shirt that is loose at the neck and wrists, long pants, gloves and a cap. Wear eye protection (safety goggles, safety glasses or a face shield or a combination of these, as appropriate). And wear a disposable dust respirator to minimize the inhalation of dust. When you finish the job, launder the clothes you wore separately and take a warm-water shower with soap. Most people report no problems when they follow these procedures.

You can find an Owens Corning Certified Energy Professional™ through the company’s Web site based on you ZIP Code. At the home page, select Owens Corning Building Materials and Services. Click on the button labeled Find a Building Professional. Enter your ZIP Code and select the words that describe your project. Another click or so and you will have the option of selecting retailers or contractors. Click here for a shortcut to the Locator page.

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Question: Should I tape the seams plus the tops of the batts instead of putting in a poly vapor barrier?

Ken writes from Lake View, New York: "I'm re-insulating an enclosed porch with Kraft faced insulation - plus spray foam around the many windows and small gaps. I am having the crawl space under floor professionally spray foamed. I was told by an insulation contractor that I should tape all the seams plus the tops of the batts instead of putting in a poly vapor barrier. The plastic creates too great a vapor barrier with possibility of trapping moisture inside the walls. My finished wall will be tongue and groove wood paneling (maybe not best for sealing drafts). Is this approach correct?"

Answer: Your approach is sound. It is not necessary to install poly over our Kraft-faced product, as your contractor stated.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:31 PM | | TrackBacks (0)

Question: Should I install new insulation over the old?

Danny writes from Elizabethtown, Pennsylvania: "I am adding unfaced R-19 to my attic which has a compressed layer of R-13 already. My home is about 50 years old and I have noticed that the Kraft paper (vapor barrier) is in very poor shape under the R-13, with tears and just general deterioration. Should I just install the new insulation over the old and leave the old Kraft paper as undisturbed as possible?"

Answer: Yes, install unfaced insulation over the existing insulation. It is usually best to leave existing insulation in place to keep it out of the landfill and take advantage of whatever R-value it is able to contribute. Fill the cavity between the joists first and then run the next layer perpendicular to the first.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 06:27 PM | | TrackBacks (0)

June 13, 2008

Question: Which of your recommendations should I rely on?

Monique writes from Ontario, Canada: "I'm finishing a basement and adding sound proofing. Per an Owens Corning brochure obtained at my local Home Depot, when installing a drop ceiling and QuietZone above it, you recommend the QuietZone be within the lower portion of the joists and that a vapor barrier be attached to the underside of the joists to further improve sound proofing. However, I just read one of your responses on this blog site whereby you don't recommend a vapor barrier be installed when QuietZone and a drop ceiling are used. SO I don't know which of your recommendations I should rely on! Please clarify."

Answer: I regret that the brochure message is unclear. A vapor retarder is needed in the floor assembly only if there is an unheated space on one side of the assembly.

If there is another living space above, no vapor retarder is needed on the insulation. If there is unconditioned space above, we recommend that a vapor retarder be used (retarder toward warm-in-winter side of the assembly). Faced insulation should not be used if the space above the ceiling is a plenum.

For an acoustical assembly with QuietZone® insulation and a drop ceiling system, there no vapor retarder is required.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 10:51 AM | | TrackBacks (0)

Question: Can I use fiberglass insulation with a backing over cellulose?

Ben writes from Rexford, New York: "I have a home built in the late 1970's in upstate New York. The attic has a good amount of blown in cellulose. There a soffit and ridge vents. I have a fair amount of moisture collecting in the attic causing mold. I checked under the cellulose and there was not vapor barrier installed. The attic is not finished and only has spaced 2x4s with drywall attached below. Can I place a vapor barrier or fiberglass insulation with a backing over the cellulose? I am hoping that I do not need to remove the cellulose to install a vapor barrier."

Answer: Cellulose is not a product Owens Corning manufactures. However, I can address this situation as it relates to fiberglass insulation. If ventilation is adequate, a vapor retarder is not always needed in an attic floor. The recommendation is one square foot of net free ventilation for every 150 square feet of attic floor when no vapor retarder is used.

In addition, it is common to see some condensation in attics in the colder winter months, especially when the insulation installed in the attic floor does not have the recommended R-value. Further, when Fiberglas insulation gets wet its R value is reduced.

In short, if you have proper ventilation, I would add more insulation (unfaced) to the attic floor.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 10:48 AM | | TrackBacks (0)

Question: How should I insulate the ceiling of my garage?

Rick writes from Birmingham, Alabama: "My bedroom is over an uninsulated garage. During summer months the heat from cars heats up the bedroom. My garage has a sprinkler system but no insulation in the ceiling. What can I use that is fire proof and doesn't require sheet rock?"

Answer: You can install Kraft-faced fiberglass insulation in the ceiling of the garage with the paper facing up toward the warm-in-winter side, which is the conditioned living space. You should check with your local building code to be sure but most areas do not require the fiberglass to be covered.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 10:45 AM | | TrackBacks (0)

June 12, 2008

Question: Should I insulate over the porch?

Irene writes from Huntsville, Alabama: "I live in a small (1200 sq ft) home built in 1912. One story frame. The attic is continuous the length of the house, including over the porch. The over-the-porch section has no insulation on it, though the rest of the attic has R38. Since it is essentially one room, wouldn't I want to insulate over the porch area?

The existing insulation is the on-the-floor kind. New roof, architectural shingles, ridge vents and power vent & louvers on eaves. I am also seriously considering having cellulose insulation blown into the exterior walls, as there is none. Inside walls are plaster. I have had wiring checked. Comments?

My heating/ac bills are disproportionately high for neighborhood. AC isn't bad; it's heating the house. 2007 HVAC SEER 14. Gas/elec.

Also ductwork is in unheated crawl space. However, under the pink insulation. Would I likely need to retro-insulate ducts too? Or perhaps the crawlspace insulation is adequate since it is over ducts."

Answer: No. It is not necessary to insulate over the porch. Cold air that enters your attic through the ceiling of the porch is prevented from reaching the living space by the insulation over the living space. Insulating exterior walls is definitely a good idea. I recommend calling an HVAC contractor regarding your home's duct work and whether insulating it will improve your system.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 10:51 AM | | TrackBacks (0)

Question: What materials would allow us to achieve our goals?

Jon writes from Saint Paul, Minnesota: "We are converting an existing screened porch into living space and would like to have R38 in the ceiling. The ceiling is 2x4 with a tin roof above. We want to maintain as much ceiling height as possible. What materials would most effectively allow us to achieve our goals?"

Answer: Owens Corning manufactures R-38 fiberglass batt insulation. The product is 12 inches thick, 48 inches long and 16 or 24 inches wide. This would require furring out the ceiling joists quite a bit.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 10:48 AM | | TrackBacks (0)

Question: What R-value is recommended for the ceiling and side walls of a bonus room over the garage?

Jon writes from Saint Paul, Minnesota: "We are converting an existing screened porch into living space and would like to have R38 in the ceiling. The ceiling is 2x4 with a tin roof above. We want to maintain as much ceiling height as possible. What materials would most effectively allow us to achieve our goals?"

Answer: Owens Corning manufactures R-38 fiberglass batt insulation. The product is 12 inches thick, 48 inches long and 16 or 24 inches wide. This would require furring out the ceiling joists quite a bit.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 10:36 AM | | TrackBacks (0)

June 11, 2008

Question: Should I install rigid foam board before the shingles go on?

Maureen writes from Monterey, Massachusetts: "I am replacing the shingles on my roof with 30 yr. architectural shingles. A recent energy audit suggested that I have the roofer install rigid foam board insulation with a foil exterior on the plywood after the old shingles are removed, and before the new shingles go on. Is this an acceptable sequence for good insulation and construction? Existing plywood, rigid foam board then felt and then the new shingles?"

Answer: This construction does not follow our recommended installation practices as it fails to include an air space under the shingle deck. For good airflow we recommend that a minimum of one inch airspace be left under the shingle deck providing for soffit-to-ridge ventilation. But since the Owens Corning warranty covers manufacture defect in the product itself, we can only offer recommendations for application. For more information, I recommend consulting a building inspector or your local building code.

Posted by The Pink Panther™ Ask the Pink Panther™ , Frequently Asked Energy Questions at 10:39 AM | | TrackBacks (0)