1907 Lumber Design Values

[Deutero]

Actual 3x12 floor joists at 16" oc for the second floor of a former firehouse wanting to turn restaurant and banquet hall.

Where can I find design values and a reasonable assumption of species for this structure built in Door County, Wisconsin in the year 1907? Keeping in mind, the lumber is likely local.

The blueprint framing plans are drawn and laid out quite nicely, but, the wood species was not indicated.

Thank you ...

 

[samdamon]

Deutero- Suggest making no assumptions about the species. Take samples of the wood and send it to the US forest products lab (Its in Wisconsin not far from you). For addtnl info on the wood testing search for previous threads on that topic in this forum. The lab can identify what species you have. Allowable stress values for various species can be found in earlier editions of the Carnegie Companion or Trautwine's Civil Engineering Handbook. (I believe you can download a copy of the Companion from SLideRuleEra's website).

Naturally you also have to also consider the quality of the original timber and its current condition when coming up with allowables to use for checking changing loads.

What is the span of your joists?

 

[bkgd]

In the Northwest of the US Douglas Fir is prevalent so on our renvoation projects we will assume a reasonable grade of DF such as DF #1 and if it calcs out that is fine since you know the wood is vigirn growth and is likely more similar to Dense Select Structural or even very dense select. You can determine pretty easy if it is DF or Hem Fir by inspection.

If that does not do it and higher values are needed we hire a lumber grader for a very reasonable fee that will go out and grade the lumber in situ. In the recent past it has ran about $500 per day and he can grade quite a bit of timber in a day. You may check with a local timber company for graders in your area.

Not sure what type of woods are common to your locality

Hope this helps