Single Boarded House (Plank House w/o Columns) - IBC 1

[Jerehmy]

In my area, what people call a single boarded house is one that lacks wall studs or columns. Instead, the wall framing is comprised of a continuous panel of discrete vertical plank members. The planks are fastened to rim beams and end joists. The connection is made by lapping the plank to the exterior side face of the rim/joist and face nailing the plank to the rim/joist. There are no columns.*

I have an issue where there was fire damage to a portion of a single boarded house and sections need to be replaced wholesale. I'm going through the IBC, and I'm trying to find specific provisions that allow this type of construction. Due to the severity of damage, the IEBC requires the structural repairs abide by the IBC.

IBC section 2304.3 states "The framing of exterior and interior walls shall be in accordance with the provision specified in Section 2308 unless a specified design is furnished". If we "specify" a single boarded design, are we covered here in terms of structural as long as the loads work out?

Anyone have any insight? Thanks



* If I google single boarded or plank construction, most details show columns somewhere. I've never seen a single boarded or double boarded house with columns so I wanted to specifically define what I meant.

 

[dhengr]

Jerehmy:
Well, why not? It’s all in the details and material availability, and good engineering experience and judgement. The IBC does not cover every imaginable detail and structural condition in the universe, with an explicit section or para. of its very own. Those Native Americans and old carpenters were smarter than we are with all our fancy codes of many-many chapters, and software, etc. What they built actually worked, and after a hundred years or so, you are replacing it, not because it failed, or rotted or some such, but because it burned. The earlier versions of the UBC and IBC had some verbiage that said that the code was not intended to stifle engineering imagination and ingenuity, or new materials or different uses of them, as long as they were based on good sound engineering. They did say “Any system or method of construction to be used shall admit to a rational analysis in accordance with well-established principles of mechanics.” Since we don’t seem to know or teach these principles any longer and so few of the AHJ are engineers with some experience, we are left to fight about a bunch of incomprehensible verbiage which no one can understand or explain, and which some share of the time doesn’t explicitly cover a perfectly reasonable approach to a structural problem. But, it is still all in the details.

 

[Jerehmy]

I have no qualms with designing single boarded, I just want to make sure I'm not overlooking some important provision that restricts this type of construction. The planks are 2" thick, pretty beefy.

 

[JStephen]

Is IBC actually required for the area? If so, are there any local amendments that address the situation?
And, just out of curiosity, where is this area?

 

[Jerehmy]

Section AJ307 of the IRC permits using "like materials" for repairs. The issue is, the IRC is a prescriptive method. Section R301.1.3 states:

"When a building or otherwise conventional construction contains structural elements exceeding the limits of Section R301 or otherwise not conforming to this code, these elements shall be designed in accordance with accepted engineering practice (this is ambiguous. One can take that to mean design in accordance with IBC). The extent of such design need only demonstrate compliance of nonconventional elements with other applicable provisions and shall be compatible with the performance of the conventional framed system. Engineered design in accordance with the International Building Code is permitted for all buildings and structures, and parts thereof, included in the scope of this code."

It's in my best interest to design non-conventional construction that doesn't fall under the umbrella of the IRC with the IBC strictly for liability reasons. This turns me to the International Existing Building Code which sends me to the IBC for large repairs. And here I am!

 

[Ron]

Jerehmy..."accepted engineering practice" is a standard of care indication, not a code implication. As dhengr notes, the codes do not cover every inevitability and where the code does not clearly address an issue, sound engineering judgment must prevail.

dhengr...excellent post!

 

[Jerehmy]

Good! I want to preserve the original construction of the home. It was built in 1860s per the homeowner and I’d love to use like materials and construction but ensure it meets strength and servicability criteria. The rim beams were definitely hewn but the joists were sawn so I’m not sure how accurate that is.

The contractor was worried about “meeting code” on the repair of the home and I didn’t want him chirping in the homeowners ear after my report comes out that I missed some important provision restricting this type of construction. In addition, I’d love to explicitily state “there is nothing in the building codes that prohibits single-boarded or similar plank construction”. I’ve been through the provisions so I don’t want you to think I wasn’t doing my due diligence, I was making sure it was as I thought. And it seems to me it is!