Anyone have spray foam insulation for home ?

Discussion in 'Community Forum' started by Duster, Sep 3, 2017.

  1. Duster

    Duster 12 pointer

    I hear ya....It was recommended we get a gas one but with no access to NG we would have to rent a LP tank. That may be the way we will go as the wife wants a gas stove rather than electric. Was told a lot of people are buying tanks and putting them in the ground. By the figures we were quoted it would take 40 to 50 years to break even buy to rent. The only advantage was being able to buy gas from whoever not stuck with one supply company. Also once put in the ground it's yours if anything goes wrong over time.
     
    Last edited: Sep 5, 2017
  2. SmokeShow

    SmokeShow 8 pointer

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    On the spray foam insulation.... one thing I hear is you can get the home too air tight and would then have to put a fresh air return in the HVAC system to keep the house from being stale inside. Truth or BS?

    Ed/Barney could you explain a little more how the traditional fiberglass professionally installed is just as good as the spray foam? Also, where's the roof deck you mention spraying in the attic? Barney you say spray crawl space... I assume that means the floor joists and bottom of subfloor? What's the "outside band" you mention in the crawl space? Sorry, I evidently know all the construction lingo.
     
  3. bondhu

    bondhu 8 pointer

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    On the air tight deal I used good attic vents ,we will just have to see, but I can tell you my garage is tight, you would think with how loose a garage door is it wouldn't. Now I am no expert but everything I did had a purpose Like garage has no heat or air but spraying it gives over half of the house a barrier from prevailing weather and outside conditions. Also added 2 foot over hang around house to keep water away from block and shades the inside in the summer. I know this don't relate to your question but for me this all works together. And has my electric bill right around one C-note a month for a 1680 sq ft house and I am all electric -air and heat In the crawl space they sprayed outside perimeter even the vents I installed and all the way down onto the plastic. Tied it all together and nothing sprayed on floor joist. Temp has stayed under 50 degrees winter and summer. As I said these other guys on here sound like their in the business and have way more experience than me.
    On second thought you might not want to take the advice of some one who's wife was raising hell that if I would cut out drinking so much I could build her a house. I informed her to drive me to get some more beer I will get started, when we got back I started stepping it off.:)
     
    JR in KY and SmokeShow like this.
  4. Iceman35

    Iceman35 12 pointer

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    What's the truth? Honest question.

    Judging by the "professionals" I see putting fiberglass in houses in my subdivision, there's not a chance spray foam isn't better.
     
  5. barney

    barney 12 pointer

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    Spray foam is good stuff, don't get me wrong. It really shines at completely sealing off drafts in a structure if it is installed correctly. It should be installed by a company with experience, and knows what they are doing though. I've heard horror stories about improperly installed foam. If the framing and foam are of different temperatures, or the foam components are not at the proper temperature at the time of installation, the foam can separate from the studs leaving an air gap to the exterior. This is where warm, moist inside air condenses where it meets cold air that infiltrates the gaps between the studs and foam. This condensation leads to mold, mildew and rot. Any good insulation job begins with a neat, and properly installed house wrap, with the seams sealed with tape.

    The two types of foam I know about are closed cell, and open cell. Closed cell is more dense, and has a higher R value than open cell foam, it is also water proof AND more expensive than open cell foam. This would be the choice foam for encapsulating a crawl space just as bondhu described perfectly. Encapsulating a crawl space essentially seals it from all air, and moisture infiltration.

    Open cell foam is generally used in walls and attic, and has an R value similar to fiberglass insulation IF the stud bays are completely filled. I actually think some of the new high density fiberglass batts have a higher R value than open cell foam.
    By professionally installed fiberglass, I mean filling stud bays completely, and paying attention to properly insulate around utility entrances, and especially around electrical boxes. The roof deck is the rafters and sheathing you see when you look up in your attic.
     
  6. barney

    barney 12 pointer

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    Some of the foam guys will exaggerate on how good the foam really is to make a sell. They will claim things like foam will make their house twice as efficient as fiberglass, which simply isn't true. Some will claim that a homeowner can reduce the tonnage of their HVAC unit in a foamed home, when actually the HVAC guys say the tonnage should be increased due to conditioning more space. Again, properly installed foam excels at sealing off drafts.

    Up to code, is up to code whether you use fiberglass, or foam!
     
    Last edited: Sep 13, 2017
  7. Marsh CallUser

    Marsh CallUser 10 pointer

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    Buddy of mine did spray in and has been in his house for 7 months. 2200 sqft house, with 25ft vaulted ceiling in great room. He told me his most expensive electric bill(has electric heat and air) was 100 and change. I realize that is only one example, but that's a pretty solid one IMO. Time will tell how well that holds.
     
    bondhu likes this.
  8. SmokeShow

    SmokeShow 8 pointer

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    My questions were for my own curiosity but a coworker is in the planning/bidding stages of building a home and is hearing arguments from both sides so I was curious... About the HVAC tonnage, his HVAC guy (a relative of his but also has a good reputation in the BG area) says he'd reduce the tonnage by 1 ton for his house if he foams it... Interesting given your response above...

    Hmm so much info is conflicting it makes it hard to make a decision. Not just on this stuff, but anything a person may try to research. Find one source says its absolutely this. Find another source says the opposite. It seems to be that way on any question imaginable. Makes my head hurt because I over analyze every big decision. LOL
     
  9. ptbrauch

    ptbrauch 12 pointer

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    I don't know that I would welcome a reduced tonnage on a house regardless of the insulation level. I've been doing a lot of research on HVAC system sizing for our new house and I've found that its not so simple as to say something like add this much insulation and reduced the tonnage by this much. Its much more complicated than that. I've also learned from what I've read, a lot of HVAC guys don't know how to properly size a unit for a house. They often just guess or just assume that they install a certain tonnage unit in a certain size house, regardless of the differences. Say they always install a 2.5 ton unit in 2000 sq ft houses. But the same size house on a shaded lot with all the windows on the north side of the house will have different cooling demands than the same house with twice the amount of windows on the south side of the house.

    I've also learned that there's other issues with going too big on a unit too.
     
  10. barney

    barney 12 pointer

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    I understand completely! I'm not against spray foam by no means, but I really want to know more about it. Surprises like having to completely replace a roof deck a few years into a mortgage on a new house spooks the hell outta me! The only thing I'm 100% about at this point is encapsulating the crawlspace.

    About the HVAC. When a house is completely spray foam insulated the crawlspace, and the attic become conditioned air space unlike a traditionally insulated home where only living space is conditioned air. That fact alone could nearly double the space being heated and cooled.
     
  11. barney

    barney 12 pointer

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    It is become completely evident to me over the last few years by talking to different contractors, that the spray foam business is learning as they go.
     
  12. Iceman35

    Iceman35 12 pointer

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    Cool. I was just curious.

    Yeah, twice as efficient is a long stretch. Don't know about he HVAC, other than every neighbor of mine, including myself, has a unit that barely meets the needs, and not a one was balanced, or set up correctly, and some neighbors have already replaced parts on units that are less than 5 years old because of it. This was my third house, so a condition of my purchase was for them to properly set up and balance the system. They were here for 6 hours. On a new house.

    My comment on the lack of professionalism is just that. The people installing rush through and aren't properly cutting or installing the insulation. A lot is jammed in with no consideration for compression, or sealing up exterior wall outlets or utilities. Tape sealing house wrap? That actually happens?

    "Up to Code" is a joke, as are most code inspections in my county anyway. Apparently, 50% of code is sufficient to pass up here.
     
  13. barney

    barney 12 pointer

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    The closed cell foam is probably twice as efficient, or more than fiberglass, but it is also WAY more expensive than the lighter open cell foam. The foam guys will throw the closed cell R value around to prospective clients, but the lower R value open cell foam will be used every where except for the crawlspace. Properly installed insulation regardless of the kind is the key to efficiency.

    Like I said previously, I would use both foam and fiberglass if I were to build a new house.
     

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