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  1. #1
    Join Date
    Sep 2009
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    Albany, GA
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    Default 1st time homeowner

    Hello everybody. My wife and I just bought our first home, a 3BR/2BA 1.4K sq ft ranch with an attached garage built in 1973. This property has obviously been through a succession of homeowners and is a bit of a frankensten at this point. It is structural sound, and all of the primary systems are in working order (although a few, such as the roof and the heat pump are nearing the end of their lifecycle and will probably need replaced in the next 3-5 years).

    My big concern with the property at this point is energy cost. During the first weekend we moved in, I happened (by chance) to notice the electric meter roll 100kWh over the course of 10 hours or so. I immediately went to Lowe's and bought a programmable thermostat, and also some insulated flexible duct to repair a broken AC in the attic.

    This attic is a nightmare! The roof is supported by low-rise trusses 16" on center, so it's very difficult to move around. There's about 5 inches of loose-fill blown-in insulation over most the living area, although it is not evenly distributed and some of it has been completely removed.

    The attic is ventilated (sort of) by a fan installed in the south gable. I've noticed that this fan run at least 16-18 hours each day, but I'm not convinced that it's doing much good.

    After installing the new thermostat and repairing the faulty ductwork, I started tracking the electric meter on a spreadsheet every day. Now I'm averaging about 48kWh usage per day, which equates to about $135 per month (the rate here is about $0.091/kWh during summer months). This is an decrease of about 30% from our last residence, so I fell as though I'm making some progress.

    I understand that I need to caulk up every opening from ceiling of the living area, and essentially make the living area as airtight as possible. I'm concerned that I do not have enough insulation in the attic, and that the attic is not ventilating properly.

    These are my questions:
    There are two vents (kitchen and bathroom) plus a woodburner that all have vent stacks through the roof. We don't intend to use the woodburner at all and plan to eventually remove it (and the brick pad it sits on) to reclaim the living space in the den. Is there a way to put some sort of damper on the two vents and also temporarily seal the woodburner flue? I'm concerned about thermal transfer, but maybe I'm worrying just a little too much.

    From what I've read, I need to install about 12-18 inches of insulation. I would much prefer to use batting instead of loose-fill, namely because I can more install it myself. I'm also attracted to the idea that batting will stay where I put it and not "wander around." Can I install batting over the existing loose-fill? I realize that the batting will probably compress the fill and reduce its effectiveness, but can I offset that with the thickness of the batting?

    Sometime in the next few years, we will need to replace the the roof. I've heard that ridge vents are more effective for attic ventilation than fans. Is there any energy cost advantage to installing the ridge vent now (and sealing the gables), or should just wait until we have the roof replaced?

    Speaking of replacing the roof, what is the best material to use (we have asphalt shingles now)? My wife is pretty interested in a metal roof, because it will presumably reflect radiant heat during the summer. What's the general opinion here?

    Finally, I'm curious about low-e window film to install on the existing windows (which are large aluminum frame single glazing). The windows themselves are in pretty good shape and are well-sealed, but the front of the house faces west and gets a pretty tough dose of the south Georgia sun every day. Is the effort it would take to install this window film on 170 panes of glass going to be rewarded with any real cost savings?
    Sorry if this was a long drawn out post, but it essentially all revolves around trying to lower my energy costs. I sure do appreciate any comments anyone can provide.
    -Cameron Lashley

  2. #2
    Join Date
    Jun 2007
    Location
    Fayette County, Ohio
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    5,622

    Default Re: 1st time homeowner

    There should be a damper on the flue pipe for the wood burner and if it is fairly new you should be able to close it off. One thing to remember is heat rises so they should have virtually no affect during cooling season and the vents generally pass very little unless the fan is on.

    Yes, you can install batting over the loose fill.

    The ridge vent is going to do little unless you have adequate unblocked sofit vents.Plus you would need to make sure you have sufficient ridge vents to handle the A/C output also.

    Metal roofs are hot unless they are installed as cool roofs, that is they are installed on strapping so there is air flow under the metal.
    Jack
    Be sure you live your life, because you are a long time dead.-Scottish Proverb

  3. #3
    Join Date
    Mar 2009
    Posts
    1,387

    Default Re: 1st time homeowner

    Howdy, i would blow in more insullation the place you buy insullation from will rent you the blow in machine an in a low attic trying to install batts will drive you batty... haha

    Reguarding your roof. I would consider adding some foot square roof vents ( one for ever 600 sqft of attic). - look like darth vaders helment. Got any soffit vents? Both of these vents are easily cut into the roof before the re shingle. There are metal shingles with epoxied granuals shingles that look like cement tiles and will take higher winds then any other product and are very hail resistant. Before you decide see what shingles your home owners insurance may give you a big premium reduction if you install them....

    The window film will more then pay for itself if you install it . the stuff at lowels does 2 windows per sheet .
    on the west exposure some trees or hedges to filter the sun helps....

  4. #4
    Join Date
    Sep 2009
    Location
    Albany, GA
    Posts
    19

    Default Re: 1st time homeowner

    Quote Originally Posted by JLMCDANIEL View Post
    The ridge vent is going to do little unless you have adequate unblocked sofit vents.Plus you would need to make sure you have sufficient ridge vents to handle the A/C output also.
    What is considered to be an adequate number of vents? The house does have a total of 15 vents (some of which are partially painted over, and it wouldn't surprise me to find that some are blocked with loose-fill). I can easily clean the paint off the exterior of the vents from the outside, and once it cools down enough to spend some time in the attic, I intend to go up there and clear off the top side of the vents and install some sort of blocking around the vents to permit free airflow. Do I have enough vents for roughly 1,600 sq feet of attic, or should I install more? I'm particularly concerned about the attic ventilation because some of the asphalt shingles over the garage (which is not climate controlled) appear to have cooked. I'm hoping that some adjustments to the attic ventilation now will prolong the life of the existing roof a little bit.

    Also, can you expound on the "make sure you have sufficient ridge vents to handle the A/C output" comment? Maybe I'm missing something, but I thought the goal was to completely isolate airflow in the A/C system from the attic...
    Last edited by clashley; 09-20-2009 at 10:45 AM.
    -Cameron Lashley

  5. #5
    Join Date
    Aug 2008
    Posts
    109

    Default Re: 1st time homeowner

    Quote Originally Posted by clashley View Post
    What is considered to be an adequate number of vents? The house does have a total of 15 vents (some of which are partially painted over, and it wouldn't surprise me to find that some are blocked with loose-fill). I can easily clean the paint off the exterior of the vents from the outside, and once it cools down enough to spend some time in the attic, I intend to go up there and clear off the top side of the vents and install some sort of blocking around the vents to permit free airflow. Do I have enough vents for roughly 1,600 sq feet of attic, or should I install more? I'm particularly concerned about the attic ventilation because some of the asphalt shingles over the garage (which is not climate controlled) appear to have cooked. I'm hoping that some adjustments to the attic ventilation now will prolong the life of the existing roof a little bit.

    Also, can you expound on the "make sure you have sufficient ridge vents to handle the A/C output" comment? Maybe I'm missing something, but I thought the goal was to completely isolate airflow in the A/C system from the attic...
    You would have to do a calculation of the cubic feet of the attic, reference the capacity of the venting you have now, and determine for your climate, the heat gain, etc. enough capacity for the appropriate number of complete air exchanges per hour. There are three main scheduled calculations to be done, not just one, would need more information on the homes construction to do so. Is the garage attic space seperated from the garage? seperated from home or open? Does it have its own attic ventilation? If seperated is there insulation between? thermal breaks?

    Installing batt insulation overtop of loose blown insulation is never a good idea, can be done the other way around. Batt insulation only maintains its R value if it has no other avenue of air leakage or exchange.

    You aren't missing anything - you are correct, the exhange of air in an attic space should be isolated from the HVAC system.

    You indicated you have an older Heat Pump - have you had it serviced and tested? Is it a split system? A system that is poorly charged, or DIRTY can be extremely inefficient. Plants, fences, walls, restricting airflow near the unit will also reduce efficiency. A 70s system even if in great shape would still likely have a very low SEER.

    Is the wiring to your heat pump Aluminum? Early 70s aluminum (and 72 would likely be not the slightly safer later alloy) is known to have issues, a highly resistant corrosion area would allow less voltage to flow - and your system might be drawing more amps to run - thus an increased and less efficient usage rate through your meter. If you're running the system in start mode all the time, it too would be highly inefficient.
    Last edited by Gray Watson; 09-20-2009 at 11:22 AM.
    SPAM: never liked it from a can, can't stand it on a board forum. This board needs MODERATORS!

  6. #6
    Join Date
    Sep 2009
    Location
    Albany, GA
    Posts
    19

    Default Re: 1st time homeowner

    Quote Originally Posted by Gray Watson View Post
    You would have to do a calculation of the cubic feet of the attic, reference the capacity of the venting you have now, and determine for your climate, the heat gain, etc. enough capacity for the appropriate number of complete air exchanges per hour. There are three main scheduled calculations to be done, not just one, would need more information on the homes construction to do so. Is the garage attic space seperated from the garage? seperated from home or open? Does it have its own attic ventilation? If seperated is there insulation between? thermal breaks?
    The attic over the living space and the garage is continuous and not separated. The wall between the kitchen and garage contains insulation, and there is loose fill covering the garage ceiling. It sounds like I need to get up there up a measuring tape and get some figures to perform the calculations... is there an ****** calculator that I can use?

    Installing batt insulation overtop of loose blown insulation is never a good idea, can be done the other way around. Batt insulation only maintains its R value if it has no other avenue of air leakage or exchange.
    Ugh... I guess that means I will have to remove the loose fill. I despise the stuff and would prefer to use batting, especially since the house is on a slab and the attic is the only utility access available. I think the batting would be more modular and make it much easier to make some of the long-term improvements I want to do (recessed lighting, plumbing improvements, etc).

    You indicated you have an older Heat Pump - have you had it serviced and tested? Is it a split system? A system that is poorly charged, or DIRTY can be extremely inefficient. Plants, fences, walls, restricting airflow near the unit will also reduce efficiency. A 70s system even if in great shape would still likely have a very low SEER.

    Is the wiring to your heat pump Aluminum? Early 70s aluminum (and 72 would likely be not the slightly safer later alloy) is known to have issues, a highly resistant corrosion area would allow less voltage to flow - and your system might be drawing more amps to run - thus an increased and less efficient usage rate through your meter. If you're running the system in start mode all the time, it too would be highly inefficient.
    The heat pump was serviced and tested before closing as part of the terms of sale. The unit is a 3-ton unit that is dated to 1988. I do keep the unit clear of obstructions to ensure it gets good airflow. I don't really know too much about HVAC, so I can't intelligently answer the questions about "split system" or how the thing is wired. So far, I've only encountered copper wiring in the rest of the house. What sort of thing should I look for to understand more about the system and how to squeeze the most possible efficiency out of it (we'll replace it sooner or later, but can't quite absorb that cost at the moment)?
    -Cameron Lashley

  7. #7
    Join Date
    Jun 2007
    Location
    Fayette County, Ohio
    Posts
    5,622

    Default Re: 1st time homeowner

    Actually you can install the bats over the loose fill even perpendicular to the joists. You just have to make sure the bats are butted together. As Timothy miller mentioned you can also install loose fill yourself. Most places that sell loose fill will rent or loan you a blower.

    A ridge vent is usually only 3/4" to 1" wide, if your house is 50 ft. long that would give you about 4 sq. feet of venting if it is 1" and a contiguous 50ft. Once necessary venting is calculated you will have best results if sq. ft. of soffit vents is equal or greater than sg. ft. of ridge vent.

    Sorry about the HVAC comment, got in my head that you have a complete unit in the attic, getting old I guess.

    Jack
    Be sure you live your life, because you are a long time dead.-Scottish Proverb

  8. #8
    Join Date
    Aug 2008
    Posts
    109

    Default Re: 1st time homeowner

    Quote Originally Posted by JLMCDANIEL View Post

    Sorry about the HVAC comment, got in my head that you have a complete unit in the attic, getting old I guess.

    Jack
    How would that make a difference? Conditioned Air and return would still need to be sealed from the attic ambient air.
    SPAM: never liked it from a can, can't stand it on a board forum. This board needs MODERATORS!

  9. #9
    Join Date
    Jun 2007
    Location
    Fayette County, Ohio
    Posts
    5,622

    Default Re: 1st time homeowner

    If it is a complete unit in the attic sufficient additional venting would be required to handle the heat output of the unit.

    Jack
    Be sure you live your life, because you are a long time dead.-Scottish Proverb

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