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My contractor used a piece of scrap pressure-treated wood as a support to attach the new shower head to

mom54 | Posted in General Questions on

Could the heat and moisture cause some of the chemicals to be released from the wood even though it’s behind the shower enclosure? I plan on having children in the near future and safety is main issue here. Thank you.

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  1. ntisdell | | #1

    Being that it is within your wall, any off gassing potential is reduced.

    Your home/apartment is made of lots of different gas/particulate emitting products - (including plenty of green treated wood already) - a small piece added isn't changing the non-organic status of your home. It's location shouldn't be significantly wet or hotter then the rest of your home (except for a leak or 1hr showers) - even if it was it shouldn't effect much the off gassing potential into your home.

    Rest assured - that small board in your wall won't effect the health of your baby.

  2. BobHr | | #2

    when pressure treated wood is used on a deck you have to use special coated nails and hangers to prevent the chemicals from eating through the metal.

    I know in the boating forums I go to there talk about not using pressure treated wood in an aluminum boat.

    I would be worried about the contact with metal. Both the nails that hold the wood in place and the copper piping would be a concern to me. It may take years,

    I would find out if any and all materials in the area can be used in contact with treated wood.

  3. dankolbert | | #3

    Robert's concerns are legit for exterior but I don't think you have to worry about corrosion in there. And copper should be fine.

    Are the walls closed in? If you're really concerned, it would take the plumber or a carpenter all of 5 minutes to swap it out if not. But Nick has it right - the 14" of PT in your house is not going to have any effect on anything unless you have some severe sensitivity to it.

  4. Tim C | | #4

    As pressure treated wood is regularly used in the construction of playground equipment and picnic tables, the safety of children exposed to the wood is a major consideration in the selection of the chemicals used to treat the wood. Because of this, the modern non-arsenic treatments use chemicals that have very low toxicity to humans, and are easily processed or excreted by your body; there is not any known risk to children even with significant amounts of contact.

    If my child were eating pressure treated lumber, I would be far more concerned about the health risks of the wood than of the pressure treatment chemicals.

  5. Expert Member

    ACQ treated wood is corrosive to metals on the other end of the galvanic scale. So it's fine with copper piping but eats aluminium, uncoated mild steel, galvalum etc. As long as your plumber used coated or copper nails to secure the shower head it will be fine.
    ACQ doesn't offgass the chemicals in it, they are released by moisture. So again, you are fine as long as your plumbing doesn't leak in the walls - and if it does you have larger problems to worry about.

  6. charlie_sullivan | | #6

    I trust this is a scrap of new pressure treated lumber, not something with the old arsenic treatment that has been sitting around for years? Still not an outgassing issue, but in that case cleanup of any sawdust he left would be an issue.

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