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Expected 4.5in of closed cell spray foam, only got 2-2.5in

guidoism | Posted in General Questions on

tl/dr: Invoice says 4.5 inches of closed cell spray foam but after they finished my random depth checks show 2-2.5 inches. Should I ask them to make sure there’s a minimum depth of 4.5 inches? Or an average of 4.5?

Full Story:
We recently had a bunch of work done on our house: New HVAC system and closed cell spray foam in the rafters to bring the envelope of the conditioned space to include the attic. We are very happy with the new HVAC system, but we have an issue with the spray foam.

There is only one company in all of Indiana that does closed cell spray foam (as far as I can tell) and it’s very difficult to get on their schedule. Our HVAC company, who actually works with the spray foam installer, suggested that they learn how to install the insulation and do it themselves. We were actually pretty happy with their suggestions. They had the manufacturer (DAP) come out to our house on day 1 and train the guys. 

The contract with them says 4.5 inches of closed cell spray foam but I just did a few random depth checks and it’s mostly only 2-2.5 inches deep. 

Is this normal? For example, is 4.5 inches specified in the invoice really a nominal depth where the actual depth is variable and not expected to be that high? 

I’m not sure what we should do? The insulation seems to be doing a great job so far. I can walk in the attic now and not feel the sheathing radiate heat to my face. But at 2 inches it only has an R-value of 12. And we apparently paid for 4.5 inches.

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  1. Patrick_OSullivan | | #1

    Not okay.

    Installers who spray a lot of closed cell are very good at getting accurate depths because closed cell is a pain to trim back. There will be some variability in a good install, but I would expect it to be 4.5" +/- 0.5" (i.e. 4-5 inches).

    If the discrepancy is as consistently large as it sounds, they will hopefully realize their error.

  2. Expert Member
    DCcontrarian | | #2

    Closed cell foam can't be applied in layers more than about 2" thick, if it's too thick it falls off from its own weight. If it was supposed to be 4.5" they were supposed to do two layers.

    You paid for two layers. They only did one. Have them back.

    1. Expert Member
      Michael Maines | | #7

      HFO-blown foam can be installed as thick as 7"--another reason to use it instead of legacy, climate-damaging HFC-blown foam. Part of the reason for the limit in depth is the weight, but from what I understand, it's more about the heat of the exothermic reaction--if installed too thick, it gets too hot and creates large voids. HFO-blown foam's exothermic reaction is not as strong as HFC-blown.

      1. thedman07 | | #13

        I was under the impression that the thickness also affected the ability of the foam to outgas as it cures and if it is too thick, it might not cure properly and could slowly leach out chemicals that can cause serious issues (like smells) that last pretty much forever. Heat could be the main driver too, I'm not an expert.

        If the manufacturer's specs allow that thickness, then I would assume its correct, obviously. I can totally see why that would be something that they would work on. Being able to spray 7 inches in a pass instead of 3 or 4 passes would make a huge difference in labor cost.

        1. Expert Member
          BILL WICHERS | | #15

          The foam manufacturer will specify the maximum allowable "lift", which is a layer of spray foam. If you can put up to 3" on in one pass (one "lift"), but you need 6", for example, then they have to spray a second layer after the initial cure of the first layer. This can typically be done pretty quickly, such as spraying the first layer, then going back to the beginning and spraying the second layer.

          As long as the material is installed per manufacturer's specifications, you're OK. If they try to put way too thick lifts up, then you can have curing problems.


  3. Expert Member
    BILL WICHERS | | #3

    Try to get a MINIMUM thickness stated in the contract, not an AVERAGE. Average thickness doesn’t work out the way you want in terms of R value, and it’s really R value that you’re looking for here, not just thickness of the layer of spray foam.

    It does sound like they should have done a second lift (layer) to hit the target thickness. If they’re a new crew, they might not be very familiar with the amount of expansion they get from the foam, although they should have checked. Standard practice is to get a piece of stiff wire and poke it through the foam in a number of spots to check thickness. If the layer is too thin, then add more over the top. The spray foam crew I usually use likes to give their customers a can of blue spray paint near the end of the job, and have the customer go around and mark all the spots that need some more foam. I mark all the thin spots and holes, then they come back and spray more foam in all the blue spots. This usually works pretty well.


  4. guidoism | | #4

    I have learned my lesson. The invoice literally says the following "Insulate Roof Deck with 4-1/2 inches of DAP Closed cell foam" and their response was that this means that "the insulation should be an average of 3” and a maximum of 4.5 inches". They are planning on coming back to full in the low sections but I don't feel good about imprecise language.

    Is there anything that would make you think that the language of the invoice would mean that?

    1. StephenSheehy | | #5

      Given the inevitable variations in thickness from a spray foam application, the only reasonable interpretation of the language is that, as noted by others above, you're entitled to an average thickness of about 4.5".

      1. Deleted | | #9


        1. guidoism | | #12

          They pulled the 3" completely out of thin air.

    2. Expert Member
      DCcontrarian | | #6

      The words mean what the words say, unless there are other words that say they don't.

      Any ambiguity in a contract should work to the favor of the party who didn't write the contract.

      1. Expert Member
        BILL WICHERS | | #10

        >"Any ambiguity in a contract should work to the favor of the party who didn't write the contract."

        That's usually how it works -- ambiguity or bad wording goes in favor of the party who did NOT write the contract, which makes sense, since it provides a disincentive to try to do sneaky things when drafting legal documents.

        I think the installed could argue that they meant an average of 4.5" with their wording, but there is NO WAY that a statement "we'll sell you 4.5" would EVER mean LESS than that EVERYWHERE. I would certainly challenge this.

        The usual way it works for things being sold, which have some legal requirements in terms of correctness (notice how pumps at gas stations are all certified and sealed, scales near the fruit at grocery stores say "not for sale" or similar, since they aren't certified the way the ones at the checkouts are, etc.), is that a tolerance is specified or implied. An example: electric meters in my area are required, by the state, to meet a specified tolerance of +0%/-1.5% (I'm guessing at the - range, since I don't remember and don't want to bother looking it up right now). What that means is that the meter is NEVER allowed to read OVER "correct", so any error has to be in the CUSTOMER'S favor. It can be up to 1.5% off in terms of reading under "correct", which would mean you're getting billed for LESS power than you actually used.

        Any document that specifies and absolute with no tolerance can be taken to mean that that depth needs to be hit, using legal lingo per my attorney father, that would be "commercially reasonable". That "commercially reasonable" means that, basically, if you were to ask a group of sprayfoam installers what they would consider "reasonable" in this case, that would become the legal definition of what "reasonable" meant for this particular case. For spray foam, most installers are going to say that a reasonable interpretation of a contract specifying "4.5" of spray foam" means an AVERAGE depth of 4.5". If you were to go to court over this, that's the likely outcome, and the installer would be required to add more sprayfoam to your project.

        BTW, simply mentioning what I said above is likely to get your installer to fix things. My dad also liked to say "it's not usually legal action that gets things done, it's the THREAT of legal action that gets things done".


    3. Expert Member
      Michael Maines | | #8

      Usually the installed thickness has to do with meeting code-minimum R-values. If you need 4.5" to meet your R-value requirements, they should know that and should have installed a minimum of 4.5".

    4. Expert Member
      DCcontrarian | | #14

      Since you know the manufacturer -- DAP -- ignore us, ask them.

      I suspect DAP will come back and say that the way they installed is not acceptable. You may want to mention that the crew got factory training the same day they did the install.

      At a certain point you have to decide how far you want to take this, whether you want to pursue it or just let it go. If you want to pursue it, go back to the installer with what you learn from DAP and insist that they install it to the manufacturer's specification.

      If they refuse, one strategy is to let them know that to sell one product, and knowingly provide a different, inferior product meets the definition of fraud. I don't know how things are where you are, but in many places the local district attorney is eager to pursue cases of consumer fraud, particularly when the victim is a homeowner. In some cases the DA will say, "nah, that's just a business dispute," but if you can get them interested that's much better than hiring your own lawyer.

      The other angle is to call around at DAP and see if you can find the guy who did the training. He should properly be mortified that the crew he just trained did this to you. If he isn't, find his boss.

  5. nynick | | #11

    The fact that they're coming back is a good sign. These situations can be touchy. Treat the crew who comes back well. The "more bees with honey..." approach.

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