This 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.
- I believe these dowel colors were specific to Weyerhaeuser. What methods did other manufacturers use to indicate the core type?
- How is the core type indicated on wood doors manufactured today?
- 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?
- 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?
- And finally, how is this information being used in the field today?
Thank you for sharing your knowledge!