diy dendrochronology

I live in Vancouver Canada, my house was built in the 1950's and the basement has the floor joists of the kitchen [above it] exposed.

At that time forestry here was felling massive ancient trees. I'm curious how precisely I can establish a maximum age of the trees felled.

Obviously I could count the rings visible on the joists and subtract that number from 1950, but not having the tree's full diameter limits measurement. I understand it's possible to compare relative ring sizes with existing [cross referenced] data sets to date timber.

Does anyone have any experience doing this or able to point me in the right direction? Any resources I'm unlikely to find on Google?