# log homes



## jtom (Nov 5, 2013)

Do the boring and notching rules apply to joists on log homes?The joists are typically wider but spaced further apart.


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## Builder Bob (Nov 5, 2013)

No, the log cabin construction is outside the scope of the IRC and must be engineered...


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## cda (Nov 5, 2013)

Welcome are you building a MC-log home???

http://www.goldeneagleloghomes.com/log_home_plans/images/Master/Master_LogMansion12865AL_Rendering2.jpg


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## mtlogcabin (Nov 5, 2013)

The 2012 IRC references a standard for log home design and construction

http://shop.iccsafe.org/icc-400-2012-standard-on-the-design-and-construction-of-log-structures-1.html

R301.1.1 Alternative provisions.

As an alternative to the requirements in Section R301.1 the following standards are permitted subject to the limitations of this code and the limitations therein. Where engineered design is used in conjunction with these standards, the design shall comply with the International Building Code.

1.	AF&PA Wood Frame Construction Manual (WFCM).

2.	AISI Standard for Cold-Formed Steel Framing—Prescriptive Method for One- and Two-Family Dwellings (AISI S230).

3.	ICC Standard on the Design and Construction of Log Structures (ICC 400).


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## DRP (Nov 6, 2013)

If you check sections 401 thru 403 in the log standard it kicks it back to prescriptive for the same conditions that are prescriptive in the IRC. The span tables and provisions in the NDS would be my first choice, I think you'd find basically the same info in the free WSDD at awc.org.


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## DRP (Nov 6, 2013)

Oh, and the reason for the log standard is to avoid the situation Builder Bob just quoted... "outside of IRC, engineer required". The intent of these standards is to lessen the frequency of "engineer required" for common situations, which in this case they tried to make common log home situations prescriptive by creating this standard. As yet, it still needs a lot of work but is better than just "engineer required" every time. Timberframe is also going this route.


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## JBI (Nov 20, 2013)

Only those elements that are outside the scope of the IRC must be 'designed' - in this case the log walls. Any elements that are within the scope of the IRC - dimensional lumber floor joists for example, could still be done prescriptively. And the IRC directly references AF&PA's Wood Frame Construction Manual for species, loading conditions, etc. that are not provided in the IRC Tables.

Short answer, if the joists can be found on a span table, they can be designed prescriptively and the drilling, cutting, boring and notching limitations would apply.


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## JBI (Nov 20, 2013)

and as mtlogcabin points out, the 2012 IRC references a log home standard.


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## DRP (Nov 21, 2013)

Wood Structural Design Data, chapter 1 pages 39 and 40 discuss notching of heavy timber beams, it reads the same as the code referenced NDS. Basically the same notching rules as the IRC with the exception that 4x and wider cannot be notched on the tension face except at the ends .


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