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If you could only choose one this year - Insulate crawlspace or Seal ducts?

Post in 'DIY and General non-hearth advice' started by mfglickman, Sep 10, 2012.

  1. mfglickman

    mfglickman Minister of Fire

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    We have a 0% loan through a CT org to make some insulation/heating duct improvements. BUT we can't afford to do more than $2,500 of work this year. This means we can EITHER get the ducts in the house sealed (ecs-aeroseal.com is a company that seals the ducts in the walls - which is a big problem area for us) OR we can spray foam the floor of the family room, which is the largest room in the house (35X20 ish) and where the wood stove is located. The MBR is above. There is currently no insulation under the floor.

    The ducts are also not sealed and there are definitely leaks in the walls (cold a/c air blowing through electrical outlets and llight switches etc., poor air circulation/little/no heat to 2nd floor).

    So there's no doubt both need to be done - but which should be done first?

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  2. MaintenanceMan

    MaintenanceMan Burning Hunk

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    Personally I would opt to insulate the crawls space. Having done this to some extent myself I would say it has made a difference in our home.
  3. Highbeam

    Highbeam Minister of Fire

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    Since you heat with wood, duct sealing is not very important. I had my floor insulated, there was none, and it made a huge comfort difference.
  4. midwestcoast

    midwestcoast Minister of Fire

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    Another vote for the insulation. Highbeam nailed it.
    Unless:
    Is that the only part of the house with uninsulated floor over a crawlspace? If not I'd suggest getting it all done at once even if it means saving another year.
  5. mfglickman

    mfglickman Minister of Fire

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    We have batts to insulate the other two smaller crawlspaces, as they are easier to access. The one I'm thinking of is big, and accessed only on hands and knees (what were they thinking?). So I'd like to think I'd do it but I know my claustrophobic self and I know I won't go in there. One mouse on my head far from the entry hole and I'll die of a panic attack. ;)

    I wish there was a DIY for foam spray insulation. I found one version of it but it was almost as much to buy the gear and materials as it was to do the space.
    PapaDave likes this.
  6. ohiohearthstone

    ohiohearthstone Member

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    Finally, a post I can comment on. I have just completed doing some spray foam in my 2 1/2 foot crawl (over 2100 square feet) withf DIY spray foam.
    This is my second project with foamitgreen.com out of Chicago. The website has every detail and information you need to learn how to do it.
    Yes, there are other companies, but the customer service and all the extra's you get with a kit is what sold me. It is a 2 part system brown/blue to make green to show you it's a good mix. Other companies are just white and the foam turns to liquid if you don't have it right. While it does cost money to do it, it saves time and money because batt insulation does not belong in a crawlspace. Be glad your builder did not use batts...you would of just been inviting mice in.
    You are probably supposed to have R25/R30 there but I believe Spray foam at half that value works because it makes a "total seal" where as air moves around batts.
    All you do is hook em up, and spray it on like paint. With your 700 square feet, you could do 3 or 4 600 square feet kits (r6.7 @1 inch) and be near your budget.
    I can give you more information: just pm me.
  7. semipro

    semipro Minister of Fire

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    I'm not sure it makes sense not knowing all the constraints of your choices but I'd suggest not foaming the floor and instead insulating the whole crawlspace as described in this white paper at Building Science.
    http://www.buildingscience.com/documents/information-sheets/crawlspace-insulation
    This assumes that the crawlspace has underground walls and is not open at the outside.

    I realize this might meet your budget requirements but foaming between the floor joist may be a waste if you later insulate the crawl space properly.
  8. Read post 5!

    Foaming the floor will trap any moisture in the crawl space. And lead to mold or rot.
  9. woodgeek

    woodgeek Minister of Fire

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    Before I did anything costing $2500 I would spend more like $500 for a (real) energy audit and then make an informed decision.
  10. semipro

    semipro Minister of Fire

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    Sorry. Missed that. Take it as a compliment.
  11. ohiohearthstone

    ohiohearthstone Member

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    In the last month, I have spent countless hours reading about crawlspaces. While it is true that many in the industry are pushing for homeowners to seal their crawl vents, and turn their crawl into a "conditioned space", this is not always the best solution.Our crawl is low on the water table and we get water under the house (even with
    perimeter tile) because the field next door floods to 24" sometimes and the ditch backs up with no where to go. Sometimes I have to laugh at the "experts" on the Internet who are quick to to "direct" someone to do something that may not be the right solution for the area. In our case we need vents. While we still need vents (they are blocked in winter) -they do bring hot humid air into the area. The solution to this is a crawlspace fan with a dehumidistat. You can look at such products from smartvent.net/Tjernlund.com.

    The building science consensus is that you should only foam the walls if you are going to turn it into a conditioned space, otherwise you need insulation in the floor. The notion that foam on the floor will trap moisture is not correct (imho). Closed Foam is waterproof and creates a total/better seal than batts. I was fairly amused to find 1/4" gaps in the floor where I could see daylight. All these gaps were doing were allowing the damp air/rodents/mold/and god knows what else an entryway. Additionally, I'm sure this was strengthening the stack effect because there was a constant stream of air to replace the air leaving the roof line. My hope now is that the house will warm up better instead of literally trying to heat the outside air



    If anything, batt insulation allows air flow=therefore also trapping stuff. Batt insulation that is brown=showing you air movement. Articles that suggest turning your crawl into a conditioned space tell you to cut holes in your floor (for air movement/equalization) and/or pump HVAC air into the space. If any of you are like me and live in farmland, the last thing you want to do is give rodents a direct entrance to your house. With our water situation, no amount of vapor barrier could "hold down" the water. Eventually the water would overtake the sump pump and have no where to go. Now if I went with "the experts" idea of a conditioned space....In a flood I would be left with a closed crawlspace with standing water-with nothing in the floor to block the smell of stagnant water. Not trying to anger someone, just trying to share some of my viewpoints/insights that I have learned while doing research. I understand that the industry is in a transition zone between old school and new school. There have been countless studies done by reputable people including habitat for humanity showing the direct benefits of spray foam. What I find ironic is that the industry has embraced small cans of DIY spray foam (great stuff, etc) but when a bigger DIY product of spray foam comes along, the big daddies in the insulation business (including OC /JM in my backyard) do what they can to playdown spray foam. God forbid, they might be pushing the "wrong product" for the job.
  12. Highbeam

    Highbeam Minister of Fire

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    Your house with a wet crawl is a problem. That problem was caused by a mistake when the house was built. Don't let one previous mistake be the reason for condemning a technology that would work fine on every other house not built the same way. I like my ventilated crawl but there are other ways.

    It's like dang, I cut off my pinky so all gloves should come with 4 fingers.
    mikefrommaine likes this.
  13. ohiohearthstone

    ohiohearthstone Member

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    Highbeam, my main idea is that one solution will not work for everyone, and there are some houses that do work "closed" and there are some that will not work that way.
    Maybe I misread your post and I'm sorry if I did.....We live in the "Great Black Swamp", and many people here have water issues due to a variety of reasons.The issues are not due to poor construction, but just due to the nature of the land/1920's ditch infrastructure. I was just emphasizing that not everyone is built perfectly with sandy soil and sewer hookup-and therefore doesnt't get to experience some of the joys that go along with country living.
  14. Highbeam

    Highbeam Minister of Fire

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    I had a wet crawlspace too, I've been there. I cringe when I see people digging holes and building houses in them with crawlspace floors at footing grade.

    Don't you think that your house could have been built higher? The footing would of course still rest on solid earth but then add extra stem wall height and fill both outside and inside the crawlspace until the crawlspace floor was above the surface grade? There is no reason to build in a hole, especially in a swampy environment.

    Now making a septic work in a swamp is another challenge but this has nothing to do with your wet crawl either. A flooded crawlspace is always due to a mistake made along the way. Yes, poor construction practices. The soils also have nothing to do with why your builder chose to put your house in a hole.

    If for whatever reason you have moisture problems in your crawlspace, a ventilated crawl is superior. It is not a one size fits all solution. We agree on that Ohio.
  15. ohiohearthstone

    ohiohearthstone Member

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    Absolutely, the house could of had another layer of block laid. Please realize that my father helped build this house *1977* and not everything would of been done the same if built today. They built what they had with what they had. My parents didn't have the $$$ that some people have to hire a Nasa engineer/surveyor, etc. to come out and do some research. Our house was done in a cut out of farmland. At the time there wasn't the problem with major flooding. What has changed is the town has tippled and now dumps all run off into one undersized ditch that runs down a state highway. The velocity/pressure is so great that side ditches cannot drain. We've tried the government route of having things inspected. (Realize this is Ohio: Common sense would say that ditch running under State Route is a state ditch. Nope! State says ditch is a county problem lol.)

    2. There is no reason to build in a hole, especially in a swampy environment.: Well that's about 80% of NW Ohio, I guess we all have to move!:eek:

    3. "The soils also have nothing to do with why your builder chose to put your house in a hole"
    Hole. That's what NW OH is! Have you ever seen OHIO clay lol? When water cannot get through the ground , it has no where to gur home issue is more of a fissure I think.. Hopefully some new field tile will divert it.

    Overall, I'm happy at some of the improvements that I have been able to make to the home. I think we're all here because we are hard workers, and do try to do things for ourselves. All I was stating was some of my experience and results with spray foam. Best Wishes to mfglickman with your project!
  16. Highbeam

    Highbeam Minister of Fire

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    I don't think you get it. You never have to build in a hole. You raise your home so that you are above the hole and backfill whatever excavation was used to place the footing. In ALL cases. It doesn't take a rocket scientist to make sure that the dirt level outside of the home is lower than the dirt level under the home. The only cost is added stem wall height and fill material. This to avoid having to deal with a flooded crawlspace.
    save$ likes this.
  17. save$

    save$ Minister of Fire

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    It is a toss, the OP also states that they are loosing AC, so, it is not just about heating. Is your wood stove your major heat souce or a supplement? What is it costing to run your AC? I would have to think hard about getting a fix that is for both heating and cooling vs. just supplemental heating. A comprehensive energy audit should come first. Where funds are limited, best to target the problem based on an objective review.
  18. ohiohearthstone

    ohiohearthstone Member

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    no, I don't think you get it. I normally don't vent my frustrations online, but I don't think it's fair to play "arm-chair engineer".In order to totally understand a situation, one has to be there to realize there are many factors in play).
    Feel free to bring your ridiculous f-350 or whatever it is out and take a look. (instead of delivering insults and cutdowns) This isn't kindergarten anymore. My point is that a closed crawl is not 100% ideal for everyone. If water has no where to go (due to environment or infrastructure) it will override the barrier and sump pumps. It wouldn't matter if we were another two feet up, we'd still have dampness/floods that would over-run a closed barrier system.
    Peace-out
  19. Highbeam

    Highbeam Minister of Fire

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    Not an arm-chair engineer. I'm a real engineer with an actual stamp. You just don't understand physics and seem to be defensive of how your dad built your home in a hole. Vapors from moisture from the earth below should be blocked in all homes by an adequate vapor barrier.

    Either way, we agree that if you can't control liquid water then you shouldn't go the closed crawl route.
  20. ironpony

    ironpony Minister of Fire

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    no disrespect to your engineering degree and PE stamp HIgbeam, but here in Ohio with our vastly varying soil conditions and soil types making a broad statement as you have really does not work.
    I started my career on Long Island, N.Y. and moved to Ohio, basically had to re-learn and regain experience in the existing conditions before I could make decisions, totaly different circumstances.
    You of all people with your knowledege should understand that. I do enjoy reading your posts and gaining knowledge from your experience. You are 90% correct in your statements above but without experience in our local conditions you are off base. Please do not take this as an attack on your experiece/knowledge, just constructive critisism. I read your post on the builing you are working on and what you are doing there would not need to be done here, ( post sizing, hole depth, concrete around posts)so if I was to comment that you are doing it wrong based on OUR standards you would be typing me the same explanation.
    Regards,
    IP
    and I also have a stamp................
  21. ohiohearthstone

    ohiohearthstone Member

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    Thanks Iron Pony!
    Highbeam, I do get defensive a bit, because while my dad was not the GC, (he finished house after framing basically) he was a jack of all trades and my hero.
    (not bad for a high school graduate)
    He taught me and my brother what work is, and how to "at least try to do something yourself." He worked his whole life to provide for us as a GM technician but only managed to pull no more than $9 his whole career. Unfortunately, he had two massive heart attacks and developed Cancer. We grew up at times with no power or heat in the middle of winter. I remember when I was 4/5, my mother tried to get some social assistance but was told that because she worked for the state(as a typing assistant -literally min. wage) that we were "rich" and therefore ineligible for aid. When my father passed away, we had no insurance and a my mother got the $150,000 mortgage. When your money is paying medical bills- you can't always make a mortgage.What's even funnier is that my mother does not get any of my fathers social security, because she was a state employee and therefore "rich". While $400 a month wouldn't be much, it could help. Ohio is one of a handfuls of states with this crazy law. I continue to live at home to take care of the property, and finish the house by reading and learning.
    This is even hard for me to do because I took the "stupid route" by earning an M.A. and now thanks to Ohio's economy, get turned down at McDonald's because "I wouldn't most likely stick around." With my father's spirit, I started working in the pizza business at 14 (helped pay through college). That's pretty much my work experience along with 20 years of helping with fair concessions. On a recent interview with a V.P. for a bank in Columbus, I was told that my application could go no further because "they don't consider restaurant work to be real experience." I've maxed one credit card (due to food and gas to get to p/t low paying jobs (not buying x box games). I don't care what our V.P. Says--we have not turned the corner.


    I do sometimes get offended when someone says you should of done this/that, or you screwed this up, or you need to do this , this , this, and that without understanding the situation or having ever had the joys of growing up "rich" like I did in Ohio. Sorry to hang out my "laundry", but I'm proud of what my father accomplished with his health. It's just situations like mine that make me frustrated that lottery winners in Michigan can continue to get food stamps and senior citizen volunteers on a school bus get sent $700,000 for getting yelled at by kids.
    I always thought it would be cool for homes/situations like ours to get one of those "make overs" - instead of "some of the ones chosen" ...but alas...middle class Ohio, just doesn't make good T.V.


    Overall, maybe there was just some misunderstanding, you said :"Vapors from moisture from the earth below should be blocked in all homes by an adequate vapor barrier." In some Ohio cases, I'm not just talking about vapor. 85% of the time, the barrier in our house works great (and a closed system would work).
    Weather patterns have definitely changed over the years and we seem to get these weird freak winter snows/80 degrees the next day that creates floods mixed with several inch storms in spring and fall. The scene I was trying to explain is that the house is not built in a hole (we're just low/flat.) I was trying to explain that if we had a higher house (via block), this would do nothing but keep water from getting into the house. No amount of vapor barrier would be able to "hold down" the force of the water coming/shooting up through the ground.I've often wondered if pouring concrete under there would work a bit ...but at 2300 square feet, this wouldn't be cheap.
    Some people in this region try basements and have to rebuild, because even though they are "on a hill" the water moves through the ground and collapses the wall. Some of these homes were built by a million dollar engineering firm. Sometimes mother nature will still win out......no matter the mitigation put into place.
    I've often wondered if pouring concrete under there would work a bit ...but at 2300 square feet, this wouldn't be cheap.
  22. Highbeam

    Highbeam Minister of Fire

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    Okay, let's step back to basics. Please explain to me how you can flood the crawlspace of a home when the floor of the crawlspace is 10 feet above the elevation of the surface of the soil outside of the crawlspace. Explain to me how you this groundwater can somehow defy gravity and pond at a grade 10 feet higher than the earth outside. Explain to me why this elevated crawlspace couldn't just be drained out to the surface outside and allowed to pond out there. Do you guys have flooded attics is Ohio?

    Keep it very simple for me because it sounds like you guys don't have gravity there.
  23. ohiohearthstone

    ohiohearthstone Member

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    So the Mississippi river never floods either, or how about New Orleans? When water backs up (as in Ohio ditches) it has no where to go. It fills 40 acre fields to sometimes 2-5 feet deep. When a house is built in these areas, sometimes we get screwed. It can take 3 sump pumps 24 hrs a day to pump it....because it's a losing battle. I'm not sure you have ever experienced clay. Water will form it's own channels..When the ground is already saturated....it comes up. Heck maybe it's a underground spring/river. I don't have the 25 million for a core of army engineers to study it.
    If you can come out here and 1. either stop the screwy weather patterns, or 2. get the State to get their head out of their but when it concerns water movement/management I'd be ever thankful...Regular citizens can't seem to get through to them..maybe somebody from WA "with a stamp" can.
  24. Highbeam

    Highbeam Minister of Fire

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    I wish you could grasp the concept, maybe this is why you continue to build homes in holes and then cry about it when water fills that below grade hole. I'll buy that water could be 5 feet deep out on the ground for whatever reason, that happens here too. Now imagine, you built your house above grade, on an artificial hill 7 feet above the same ground. Seems to me that you have 2 feet of dirt before your feet get wet. The soil will be wet of course but not ponded. Yes we have clay, we have peat too. Your area is not special, your inability to grasp new concepts is.

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