insulation question

Discussion in 'The Lounge' started by ezbite, Feb 25, 2009.

  1. ezbite

    ezbite the Susan Lucci of OGF

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    over this winter and the past ones, ive noticed that i get alot of ice build up on my roof. i was doing a little research and it seams that without proper insulation, heat escapes thur the roof and melts the snow on the roof and it turns into ice. i went into the attic and crawl spaces and i see there is no insulation on the roofs underside, there is insulation on the walls and floor. ive also heard that you are not to insulate the underside of your roof because it needs to breath:confused: so my question is, should i replace the old insulation with something better or put some on the underside of the roof. im getting new shingles the year and i want them to last 30 years.
     
  2. Lewis

    Lewis ORIGINAL TEAM OGF

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    Does your house have vented soffits (overhangs) ?
    Blown in insulation on the floor?
    When you blow insulation into an attic floor you should use wings (dams) at the outside end of the trusses to allow for proper ventilation.
    Not using these is a common mistake that a lot of insulation companies make.
    This will keep the roof coooler and help with the ice problem.
    It will also dissapate better in the summer giving longer shingle life.
     
    Last edited: Feb 25, 2009

  3. You may need to replace the current insulation or supplement the current insulation with more " unfaced" insulation. Save your receipts and mfg cert. statment. There is a 10% of the cost up to $500 tax credit for new insulation. Also "energy star" metal roofs...
     
  4. Are the walls with insulation attic walls? If so, is the attic heated? If so, you do need to insulate the underside of the roof. To allow the underside of the roof to breathe you need to install vent channels on the underside before you put up the insulation. The are basically wide upside-down u-shaped foam panels that fit between the rafters and provide an air space between the insulation and the underside of the roof. Also need provide an opening for air to flow in and out of the vent channel at the floor and the peak.
     
  5. ezbite

    ezbite the Susan Lucci of OGF

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    no soffits, fiberglass batt on the floors and on the outside of the bedroom walls is fiberglass batt with paper on the outside. its an attic build into an bedroom. kinda like building a square box inside of a triangle. the crawl spaces are where the insulation (or lack of) is.
     
  6. The paper (moisture barrier) on the wall insulation should be on the heated (bedroom) side of the wall. Is the ceiling of the bedroom insulated? Is there insulation in the floor of the crawl space? You need it both places.
     
  7. ezbite

    ezbite the Susan Lucci of OGF

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    looks like the wall insulation is on backwards and the other is just old and needs replaced
     
  8. ICE Guard!
    It like rubber thats real sticky on one side, have them put it down on at least the first row under the shingles. If any water or ice makes its way under the shingles this keeps it from getting in the house. I think they have info on it at Home Depot or Lowes (stop next trip over to Gander Mountain).
    Good luck finding a good roofer in the area, everyone I've known thats gotten a new roof in the last few years has had problems.
     
  9. There is two reasons for the ice damn building.

    1.) Loss of heat due to not enough insulation.
    2.) Not enough air flow in attic space to keep the temps stable.

    Depending on the age of the insulation, I would look at either replacing it or adding additional to it. You mentioned the wall insulation has the Vapor Barrier (the paper side) towards the outside of the home. This is installed incorrectly. The VB should always be towards the conditioned (heated) side of the wall.

    Insulation will lose 95% of it's effectiveness when it becomes damp, and I will venture to say with the wall insulation backwards, moisture has been trapped between the wall and the VB. This will need to be replaced if wet especially because of the prime enviroment it creates for mold growth.

    If you feel you have ample insulation, then you need to address your air circulation in the attic. Without any eaves, a ridge vent will definitely help your situation, along with a thermostatically controlled fan.

    Ice damns form as the warm air in the attic (which has formed from the reasons above), melts the snow on the roof. The water then runs down the shingles to the gutters/eaves, and will freeze due to the lack of warm air (which is trapped in your upper attic area).

    Ice guard is definitely recommended if you're going to replacing your roof soon, but with proper insulation and air circulation, ice damns can be prevented. I will be adding an additional 8" of blown-in cellulose this summer and look foward to not dealing with these things anymore. Good luck!
     
  10. ezbite

    ezbite the Susan Lucci of OGF

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    can i just take the bags of cellulose up, cut open and spread out around the floor of the crawl spaces or do i need to rent the blower?
     
  11. To do it properly, you'll have to get the blower. I went to Homie Desperation this past weekend, to price out doing my garage (22x22). Will be $250-$300. I had it quoted before this winter and to do 6" was $675.

    The minimum purchase to get the blower for free is 29 bales. If I were to do an R 30 installation, I would need roughly 30-35 bales which would yield me around 6" depth. The bales at HD were $7 and change + tax.

    I had them run through the operation of the blower with any issues that can happen. It comes with 100' of hose, and the only real issue is getting the air/cellulose mixture correct as to not clog up the hose. It's just a small restrictor plate that slides in and out. I wouldn't be afraid to DIY, just do some reading on the internet.
     
  12. Hey EZ...

    Check out this product...been hearing very good things about it...

    www.reflectix.com

    I'm going to wrap my crawlspace ductwork with it, as well as put it over the floor joist openings, and probably in the attic as well between the trusses.

    You just have to make sure you leave the ends open so that air can circulate when you put it in the crawl or attic.

    I know a guy who works for a HVAC company that can get it directly from his buyer at much less than what you will find at Ace, Home Depot, etc. etc.

    BTW..the thought of NOT having to mess with cellulose or fiberglass is driving this decision for me. My Dad is a carpenter, and I've spent 100's of hours on the hopper end of an insulation blower and it sucks...
     
  13. Workdog

    Workdog "One More Time"

    heheheh...

    EZ, I did my attic with the blown in insulation 4 years ago. If you are going that route, USE THE PINK STUFF. There is MUCH less dust for the guy in the attic on the discharge end of the blower with pink insulation than the grey crap. It is pretty easy to do. One or two folks throw the insulation into the blower hopper outside, and a long hose routed into the attic is pointed by one person to spread the insulation around. If you feed the hopper too much at once it will clog the tube and that is a hassle to free up. Do this on a cool day.;) I didn't need any special clothes in the attic with the pink insulation. It comes out of the tube like snow flakes and drops into place where you put it. If you use grey insulation it will cause more dust than you can imagine.
     
  14. since you are haveing a roof done there are ways to vent from the bottom edge. you must have air come from the bottom and go out the top. if you put in a lower edge system and a ridge vent you will have to block any gable vents or the system will not work properly. as for ice guard or ice and water shield on bottom edge it is a must. i must also state that it only coves a 5 year warrenty and if the roof is not properly installed or someone thinks it will be good enough to fix all when the nails rust from the head down they will start to leak. i have roofed for 20 years and when i started no one used ice guard. and most roofs did not have felt. as for the insulation if you buy enough of it most places rent the blower for free. you will need help with a blower it does take two guys to run one. also if you do the insulation before the roof install baffles before you insulate and never block your the air flow. if you have any questions or need a roofer pm me
     
  15. My 2 cents, Bigcrappie and 5 cent hit it on the head.