I want to start sealing up air leaks in my house going into the attic. Around bath fans, can lights, anywhere that there is a break in the drywall. My question is: will regular duct tape work very well in taping plastic sheets down to the drywall or on foam sheets. I have done this in another house I had, but I am wondering about the best solution. I also have knee walls in the attic which I would like to cover with foam to stop air from moving up and down the wall cavities. Any suggestions will help.
Is this very cost effective in a mostly AC environment that we have here in the south?
Thanks,
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I was told that foil exceeds duct tape by a lot in staying power. The best company ever for smart products is 3M. See if they have a tech line. Those guys know their stuff.
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Use the foil tape. Duct tape will not hold up long term, especially in our summers.
"will regular duct tape work very well in taping plastic sheets down to the drywall or on foam sheets."
where is the plastic going? You do not want to create a second vapor barrier.
A good start would be to use spray foam in all the penetrations that you can get to.
I am planning to use the plastic to cover around and over things like the bath fan, electrical boxes for lights, etc. It would be taped down to the ceiling drywall with the loose fill insulation over the top of it. I don't think that will create a second vapor barrier. I don't think I have a first vapor barrier in this ceiling. House is about 12 -15 years old.
Thanks,
Duct and foil tape have their uses but sealing poly sheeting isn't one of them. I'd suggest using something that is engineered for the task. Venture tape (product #921CW) is superior. Tuck tape is ok but not as good as venture. Hard to find though.
It looks like the Venture tape is a heavy duty packing tape with a good adhesive to withstand the cold and heat. It looks great but I'm not going to be able to find that stuff.
Thanks,
http://www.venturetape.com/final/index.html
You should be able to order any of their products, or at least get a local retail outlet from this site.
I buy the foil Venture tape at my HVAC supply house. You can also call any of the commercial pipe insulators in your area. They will give you a wholesale/retail outlet name.
Expect to pay a premium for small quantities of the good stuff.
Dave
Aluminum Foil is superior than duct tape for sealing ducts.
For sealing the foamboard, I like to use Tyvec brand housewrap tape... STICKY!.
I just did the same thing here and discovered there was no top plate to stop the airflow from the top of the wall. (studs to rafters). I cut foamboard 3.5"strips to stud bay width and inserted them into the tops of the stud bays before covering the whole thing with 3/4" foamboard. Expanding foam at floor/wall intersections make for a much more effective application.
Something to bear in mind while you are there is to seal the joist bays (foamboard and expanding foam spray) under the kneewall bottom plates to prevent atticair from entering.
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BTW I just recieved the Nat Gas bill and was able to do a year to year analysis. After doing this very thing at our house, we are using 25% less gas (therms) for the same degree days.
IT IS WORTH THE EFFORT... though you'll question that while extracting your elbow from your ear while in the attic.
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25% WOW! I got started this weekend. I have over 50 major penetrations in the ceiling drywall so it's taking some time. I have several light cans that are letting so much light through it looks like a runway up there. Those are going to get boxed in with foam board. I'm using the foil tape on most everything else with some plastic sheeting around larger things like the bath fans. It's amazing how many things you can find in an attic to repair when you start looking around. I think I'll blow in more insulation when I get finished so I need to get it all done right this time around. Did you add any additional insulation after you had yours sealed up tight?
The only added insulation for this result was R4 foamboard to the attic side of the kneewalls... well, and pushing the batts back into the stud bays where they had been forced out during the drywall insulation >20 yrs ago.
I also foamed around the HVAC ducts and at the ends of the joist bays... the wind was running from the front of the house all the way to the back and, of course, through all the wiring penetrations to every other bay.
I got the idea from the new EPA requirements for "Energy Star" ratings on new building. They have found that exposed fiberglass insulation in an attic kneewall and at the ends of joist bays are rated at about R1 (drywall only) due to airflow within the insulation.
The effects were immediate! The second floor temps were increased drastically during the heat cycle. So much so that I installed a baffle into the upstair's HVAC supply trunk equal to abaut 30% of the duct to limit the airflow. Air temps for both floors are within 1% after a heating cycle and the temp swings have been cut in half on the second floor.
I chose a different tactic for the IC light cans a few years ago.... I applied gasketing to the rings, where they meet the ceiling, FROM THE INSIDE. I then installed CFL's in place of incandescent to lower the heat buildup and minimize the chimney effect.
The last house I made the boxes over the cans from 5/8 drywall, then covered them with more insulation. That was quite effective,Liberty = Freedom from unjust or undue governmental control.
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There's no such thing as "duct tape". It's "duck tape" and so named because it's made from duck (canvas) fabric. It's not designed or intended for sealing ducts or any other permanent purpose -- the adhesive is only good for about a year before it dries up and flakes off.
For ducts you should use foil tape. For sealing plastic vapor barriers, housewrap, etc, you should use "sheathing tape".
I just happened to get a book called "Ductigami, The Art of the Tape" by Joe Wilson for my birthday. This is from the opening chapter:The Role of the Roll: A Ripping HistoryDuring the Second World War, the United States military put out a tender for the development of a strong mending material. This material had to be waterproof and tearable by hand so that soldiers could use it on
the battlefield.A division of Johnson and Johnson Co. rose to the challenge and developed an olive-drab "military tape," a cloth-mesh tape covered in a rubber-based waterproof adhesive. This tape was first used to keep ammunition boxes dry, but it was soon discovered that this military tape could be employed to make quick repairs to jeeps and all sorts of other military equipment. Foot soldiers called the tape "gun tape." The air force used it to cover gun ports on the wings of planes, thus reducing drag during takeoff. (As a bonus, pilots could tell if a gun had malfunctioned, as a faulty gun would still be covered in unbroken tape after firing.)After the war, a housing boom commenced in the United States. Many of these new homes featured forced-air furnaces and air-conditioning, both of which relied on ductwork to move air throughout the living spaces. Though a variety of products were tried in an effort to find the best connective material for these ducts, Johnson and Johnson military tape proved superior. The color was changed from olive drab to sheet-metal gray, and that's how duct tape as we know it was born.This magical, pliable, metal-like fastener can hold almost anything together. Red Green calls it the handyman's secret weapon. NASCAR claims it's the 200-mile-per-hour tape. The U.S. Air Force ups the ante, calling it the 1,000-mile-per-hour tape. NASA actually has a policy stating that every space shuttle mission must carry at least one roll of "the gray tape" on board Remember Apollo 13 ("Houston, we have a problem")? They used duct tape to bring those astronauts home!Steve
Allen,
Word of caution. Careful on covering electrical fixtures with ANYTHING. Make sure that what you use is fireproof or rated for contact with electrical fixtures. Tape, insulation ANYTHING. Junction boxes, if any, should be considered for access if needed.
Also, do not close off needed roof ventilation. That Texas summer sun can roast things quickly in an improperly vented space.
...The unspoken word is capital. We can invest it or we can squander it. -Mark Twain...Be kind to your children....they will choose your nursing home....aim low boys, they're ridin' shetland ponies !!