No announcement yet.

cold popping

  • Filter
  • Time
  • Show
Clear All
new posts

  • cold popping

    I've not seen this matter adressed before...perhaps you can shed some light on this phenomenon. I've been hearing a somewhat pronounced popping noise at various times that seem to be eminating from the roof... sort of like a softball has been tossed at the rooftop. This may occur 4 or 5 times at various points of the day and only during the winter months. The home is 13 years old and is of typical construction for the area. Spruce framing, 2x10 rafters, 2x6 walls, 5/8 ply sheathing, etc.
    In speaking to other builders as well as friends with homes, this is not an unusual phenomenon.
    Up here in Maine it gets pretty cold for extended periods. Ordinary temperatures in the winter months can range from 10 belo zero to 20 above for weeks at a time and with snow and ice accumulation on the roof, I'm guessing these cold weather elements are contributing to this popping noise. My question is...What is actually popping?
    Is it the product of expansion/ contraction of the lumber? Additionally, this seems to happen regardless of the age of the house.
    Thanks for any help you can offer

  • #2
    Re: cold popping

    Hello Norm -

    The sounds you hear and refer to are present to some degree in most all structures. The audible popping noise can be attributed to movement between adjacent surfaces, which may "slide" on one-another and exhibit no sound, or they may "bind" and then slip which generates the popping noise.

    This movement can be the result of many factors, including:

    Thermal forces (expansion and contraction)
    Imposed loads (roof loading, wind loading, floor loading)
    Gravity (settling)
    Drying (shrinkage)

    From your description, I would think you are hearing movement between the roof structure and one or more of the following: the top plates of the walls, between the ceiling joists and the rafters, at the ridge, and at bearing on interior walls. I would probably not be too concerned unless it is "excessive" or you start seing signs of distress on the interior of the home such as sheetrock or plaster cracks and/or windows or doors that start to bind.

    These noises can be reduced significantly (most easily during construction) by either isolating components from one-another or by tying the components solidly together to force them to move in unison. Through years of experimentation we've managed to cut way down on these noises by the use of copius amounts of construction adhesive to include gluing structural components at their respective interfaces with metal connectors. One noise generator that we have not solved is with pre-fabricated trusses. Shop built trusses will always generate noises after installation due to the use of metal connectors where lumber is butt or scarfed together through the connector.



    • #3
      Re: cold popping

      If you have metal roofing, the most likely cause of the popping sound is thermal expansion and contraction of the roofing panels.


      • #4
        Re: cold popping

        Hi Norm,

        I've had customers out here on Puget Sound call me about the same phenomenon and have to agree with Justin. We don't get severe cold weather here for months on end, nor does it ever get very hot - I think it got to about 93° for about an hour one day back in '97 or '98 - but we have it happen here too. If the home had manufactured trusses, my first thought would have been possible movement sounds due to truss uplift, but since your's is stick-framed other possibilities have to be considered.

        Around here in some newer homes, you can identify these sounds pretty easily. Usually, it's OSB or plywood sheathing that has been installed too close together and tends to act like one of those little tin toy snap crickets we played with as a kid - contracting at night and expanding as it gets warmer during the day - with the panels bowing up at some times and lying flat or concave at others. Sometimes the edges are just sliding by one another like tectonic plates and making noise. Others - older homes with one-by T & G sheathing - its harder to figure out and sometimes you can't put your finger on it.

        ONE TEAM - ONE FIGHT!!!



        • #5
          Re: cold popping

          I don't have trusses but I do have a metal roof which creaks with the first rays of sun.