Printed from the blog of Lori Greene, AHC/CDC, CCPR, FDAI
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Apr 01 2014

Wood Door Dowels

Category: Doors & Frames,Fire DoorsLori @ 12:09 pm Comments (3)

Weyerhauser DowelThis post comes to you from 33,000 feet – I’m on my way to ISC-West!

A long time ago, mostly before my time, some wood doors had a dowel on the edge that would indicate the type of core that was used.  Several people have asked me to post a chart showing the dowel colors and corresponding core types.  I converted the chart from the old typewriter version to a spreadsheet, but I have questions and I’m hoping I can count on your wisdom once again to fill in the gaps.  The image of the chart below is tiny, but you can download a PDF here.

My questions:

  1. I believe these dowel colors were specific to Weyerhaeuser.  What methods did other manufacturers use to indicate the core type?
  2. How is the core type indicated on wood doors manufactured today?
  3. From the chart, it looks like there is some overlap…for example, a blue/gold/blue dowel could indicate a particle core door manufactured between 1962 and 1975, or a mineral core door (45-, 60-, or 90-minute) manufactured between 1973 and 1975, or a lead and staved lumber core door manufactured between 1973 and 1975.  This seems confusing to me, no?
  4. The gold dowel shows a B- or C-label door manufactured in 1962-63, but it’s in the particle core row, not the mineral core that is used today for these ratings.  Were these doors made with particle core back then?
  5. And finally, how is this information being used in the field today?

Thank you for sharing your knowledge!

Weyerhaeuser Dowel Chart Rev

3 Responses to “Wood Door Dowels”

  1. John Rein, AHC says:

    Wood Fire doors manufactured in the 1960’s and 1970’s most likely contain asbestos and should be properly disposed and replaced.

  2. Jennifer says:

    I’m in the same position as you are in. I was wondering if you got any answers from anyone. I have to proof that this are fire rated doors. Please if you have any info it will so appreciated thank you!

  3. Larry Young says:

    You are correct about it being confusing. I went back through my info and can add that the info from 1989 also applies to doors mfgd from 1990-1992. The dowels were discontinued by Weyerhouser in 1992 or 1993.

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