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Discussion Forum

Spray Foam Insulation and Carpenter Ants

jeeppilot | Posted in General Discussion on June 15, 2009 10:52am

I built my timberframe house about seven years ago. Wishing to build something that I would live in for the rest of my life, I spared little expense on technology, systems, materials, etc. Included in the construction was sprayed in polyurethane foam insulation. I’m now beginning to regret the choice. It seems that I now have a huge carpenter ant infestation and in talking to the local exterminators, the ants not only love the foam but are almost impossible to eradicate once established there. Can anyone corroborate the exterminator’s claims? Does anybody have a similar problem that they’ve been successful in treating? If so, what did you do to get rid of them? Any help would be appreciated as I’m nearly at my wits end. Thanks in advance.

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  1. MikeSmith | Jun 15, 2009 11:21pm | #1

    jeep...  i  wouldn't  dispair

    here is  a  great  article  on  tracking  and  killing  carpenter ants

    http://www.extension.umn.edu/distribution/housingandclothing/DK1015.html

    it  sounds  to  me  like  you've  been talking  to  exterminators  that  don't  care  about  your  problem... or  they  don't  have  enough  experience  with  carpenter   ants

    i  don't  use  untreated  foam  for   the  very  reason  you're  discussing

    we  only  use  foams  treated   with  borates

    but   still.....  after  you  read  the  articel.. i  think  you'll  have  a better  handle on  how  to  defeat  the  little  bastids

    make  sure  there  are  no  moisture  sources

    no  food  sources

      find  the  nest  ( the  satelite  nest  in  your  house   and  the  main  nest  that  they  are  moving  back  and  forth  from  )

    after  you  get  rid  of  the  nest   create  a  perimeter  around  your  house   and  keep  them  outside  of  that  perimter

    Mike Hussein Smith Rhode Island : Design / Build / Repair / Restore
  2. User avater
    Jeff_Clarke | Jun 16, 2009 07:19am | #2

    I know of one (EIFS) house where the entire exterior cladding AND foam was removed to get rid of the ants.

    Jeff

  3. wane | Jun 16, 2009 02:38pm | #3

    the ants aren't after the foam, they're after wet wood, find that and then you can deal with the ants .. check flashing, caulking all the obvious things then start thinking about what's going on in the walls where you see them the most, how/where is the water/condensation coming from ..

    1. User avater
      Jeff_Clarke | Jun 16, 2009 03:11pm | #4

      Oh they LOVE foam for tunneling - seen it many times.

      The previous owner of our house didn't know how to handle them - in one case they chewed horizontally around 6 feet through (very DRY) white oak flooring (!)

       

      Jeff

      Edited 6/17/2009 8:22 am ET by Jeff_Clarke

      1. wane | Jun 17, 2009 03:16pm | #8

        there's the distinction, tunneling yes, but they are only tunneling to get to the wet wood (ant food) ..

        1. User avater
          Jeff_Clarke | Jun 17, 2009 03:21pm | #9

          That's a mistaken impression - they do NOT eat wood at all.

          They are just as happy staying in foam tunnels and ignoring wet or dry wood since the foam is easier to tunnel.

          Jeff

          1. frenchy | Jun 17, 2009 04:16pm | #10

            Jeff,

             So ants don't need a food supply?    I suspect you are wrong, the reason they eat wood is for the sugars in the wood.   Toss a pine board on a carpenters ant site and see if they don't eat it..

          2. User avater
            Jeff_Clarke | Jun 17, 2009 04:35pm | #11

            I know what they eat and it isn't wood - you're thinking of termites.  Carpenter ants can't digest the cellulose in wood.

             

            Jeff

            Edited 6/17/2009 9:42 am ET by Jeff_Clarke

          3. MikeSmith | Jun 17, 2009 05:26pm | #12

            frenchy... if you  read  the   link  i  gave,  you'd  know  that  ants  don't  eat  wood

            they  tunnel  and  live in it

            and  they  much  prefer  tunneling  and  living  in  foam.... just  like  youMike Hussein Smith Rhode Island : Design / Build / Repair / Restore

          4. User avater
            Dreamcatcher | Jun 17, 2009 05:48pm | #13

            I am reading this thread and thinking about the new soy based foams.....Seems like soy would be much more attractive to ants than poly-based foam. What if you sprinkled borate salt like Borax on the bottom plates and sill plates before spraying in foam? BTW: Carpenter ants DO NOT eat wood.DC

          5. User avater
            Mongo | Jun 17, 2009 08:22pm | #14

            When it was a concern I'd spray the framing with Bora-care prior to insulating.

          6. MikeSmith | Jun 17, 2009 08:55pm | #15

            i've  used  Bora-Care  on  old  houses  with  damp  basements

              ( no  PT)

            i  think  the  last  time  i  bought it  paid  $125 /  gallon

            yikes !Mike Hussein Smith Rhode Island : Design / Build / Repair / Restore

          7. User avater
            Mongo | Jun 18, 2009 10:21pm | #21

            You rich island folk an afford that.Us poor mainlanders buy it for about $75 a gallon. Still worthy of a "Yikes!"

          8. PatchogPhil | Jun 18, 2009 10:33pm | #22

            How far does a gallon go? i.e. How much of an area can you treat with a gallon? Do they "rate" it in square feet or lineal feet?Thanks in advance. 

            Quantum materiae materietur marmota monax si marmota monax materiam possit materiari?

          9. MikeSmith | Jun 19, 2009 01:06am | #23

            been awhile... but if i remember it depends on wether you dilute it at 1 - 1 or 2- 1

            the rate depends on the application ( per the directions )

            so you get either 2 gallons or 4 gallonsMike Hussein Smith Rhode Island : Design / Build / Repair / Restore

          10. PatchogPhil | Jun 19, 2009 02:19am | #24

            OK, but how much wood surface area does that cover?Thanks Mike.
             

            Quantum materiae materietur marmota monax si marmota monax materiam possit materiari?

          11. MikeSmith | Jun 19, 2009 03:34am | #25

            i'd just be guessing.....200 sf  /gal ?

            bet if you google "Bora Care".......might find some  spec sheets

             

            Mike Hussein Smith Rhode Island : Design / Build / Repair / Restore

            Edited 6/18/2009 8:35 pm ET by MikeSmith

          12. User avater
            Mongo | Jun 19, 2009 05:58am | #26

            Just like paint, you'll get about 350-400 sqft of coverage per gallon.Do realize that the Boracare in the jug is a concentrate, you mix it 50/50 with water to get a sprayable solution. Or you can brush it. I always sprayed.So a gallon of concentrate should get you around 700-800 sqft of coverage.

          13. User avater
            Jeff_Clarke | Jun 18, 2009 05:39am | #16

            "What if you sprinkled borate salt like Borax on the bottom plates and sill plates before spraying in foam?"

            The BoraCare spray would make more sense.   What I did was to sprinkle boric acid powder in each stud bay.  However, the foam comes out under significant pressure.  In discussing this with the applicator he was able to reduce pressure at the base of each bay to accomodate the powder - but, a spray that would then dry leaving no residue would be better than powder.

            Jeff

          14. frenchy | Jun 18, 2009 04:46pm | #19

            Or you can simply have  borate added to the foam.. 

          15. aworkinprogress | Jun 18, 2009 05:22pm | #20

            Have some Bora care for sale from A BIG job works wonders so far

          16. BilljustBill | Jun 19, 2009 06:43am | #27

            Mike,

            I saw an odd site, several weeks ago.  During a city sponsored cleanup around the lake homes, I saw one fellow drive up to dump some junk and soaker hose...

            I happened to be close to where he pulled up and saw that as the guy pulled out a medium duty wheel barrow and several hundred feet of soaker hose, Carpenter Ants were crawling everywhere...No telling how many were left in his SUV.  The wheel barrow was old, but it had a couple of years left in it ... ;>)  There were so many ants crawing all over it, I couldn't bring myself to take it home...  The guy said he was throwing away so much soaker hose because as they lay coiled up, the ants eat holes into the hoses and live in them....

            Another indicator: If you have Carpenter Ants, check the soaker hoses that are usually near the house foundation!!

            Bill ;>)

        2. darrel | Jun 18, 2009 07:25am | #18

          If they ate the wood, they wouldn't be called carpenter ants, but rather something like beaver ants. ;o)

  4. frenchy | Jun 16, 2009 03:33pm | #5

    Too bad you didn't buy AFM panels  they have borate added to the foam and the OSB is treated for resistance. 

      By the way they don't use spray foam in most panels, they are built with block foam and pressure laminated together. 

  5. User avater
    Mongo | Jun 16, 2009 10:32pm | #6

    I had a carpenter ant problem for several years after building. Exterminators were no use whatsoever.

    So I did some research, bought several tubes of MaxForce Gel and knocked them out of my house in one season. That was several years ago, they've never returned.

  6. fingersandtoes | Jun 17, 2009 06:42am | #7

    Two colonies of Carpenter ants moved into the foam insulating my rim joists. It takes a while, but you can get rid of them. At any time 10% of the colony leave the nest to gather food. You can either give them bait to kill the queen, or keep killing the 10% until every last one of them is dead. Given that the average colony is around 2000 ants, and that they become dormant in the winter, completely eliminating them can take several seasons.

    No house I build here in the PNW forest will ever have any foam in it if I can help it.

    Edit: I spent part of yesterday replacing tiles in a bathroom of a house where Carpenter ants had eaten wide pathways in the plywood underlayment - completely ignoring the 1"x6" shiplap subfloor below. Tiles just began sinking like they had been laid on an ancient Indian burial ground. I hate ants.



    Edited 6/16/2009 11:46 pm ET by fingersandtoes

  7. gfretwell | Jun 18, 2009 06:41am | #17

    We have had a few problems with carpenter ants. We ended up finding a "mother ship" nest outside near the foundation and the nests in the house were just satellite nests.
    I suspect they still need to live in the dirt for part of their lives.
    They do build a little nest just about anywhere tho.
    They were never actually in wood. One in a coffee maker, one in our water bed and one in a big plastic diskette box along with the places you would suspect (any secluded dark spot). We caught them swarming next to the foundation one morning and dispatched them there with a bucket of something nasty. The rest were gone shortly after that.
    We were successful in getting rid of carpenter ants and fire ants, then the little black ants showed up and we have been battling them ever since. (a truce exists right now but I expect them back)
    At this point I am thinking the fire ants were not really all that bad ;-)

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