AMERICAN HARDBOARD ASSOCIATION SIDING TYPES IDENTIFYING #'S
Besides finding the manufacturer's markings on the back or identifying the pattern, you can also match the American Hardboard Association codes stamped on the boards.
Look for the AHA markings and use the following tables to help you.
See below for more pictures.
Plant Number. .......... Plant Location.. ......... ......... .... Owner
AHA01... International Falls, MN..... ......... ...............Bosie Cascade
AHA02 ...Broken Bow, OK ........ .... .........................Weyerhaeuser
AHA03... Diboll, TX.................. .... ......................... Temple
AHA04... Roaring River, NC....... ............... ............ Abitibi/ABTCO, LP
AHA05 ...Forest Grove, OR ...... ........ .......... ............Forestex
AHA06 ...Laurel, MS Masonite, ......... ......... ......... ... IP
AHA07 ...Catawba, SC Champion, GP Bowwater, ......US Plywood
AHA08... Ukiah, CA Masonite, ......... ...... ............ ......IP
AHA09 ...Not used for siding ......... ....... ......... ...........Not used for siding
AHA010... Klamath Falls, OR ......... ......... ............... Weyerhaeuser
AHA011... Sturgeon Falls, ONT MacMillan, ..............Weyerhaeuser
AHA012... Towanda, PA Masonite, ......... ......... .........IP
AHA013 ......... Not used Not used
AHA014-19 ......... Not used for siding Not used for siding
AHA20 Klamath Falls, OR ......... ......... ......... ......... ...Collins