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Small Cabin Forum / Cabin Construction / Support with Cabin Design in Northern WI
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gedna002
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# Posted: 1 May 2022 09:46 - Edited by: gedna002
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Long time lurker. Looking for support with our build in Northern WI. We're doing a FPSF. We purchased these plans https://www.cabinplans123.com/details.php?plan=C0560A . I talked to the company before about known issues building in WI. I anticipated that I would have to lightly modify but the inspector said those plans won't work in WI. He mentioned minor issues but the big one was the front wall. The front wall needs to be engineered. The plans come with beamcheck files for all the rafters and joists. Overall the plans seem to be quite thorough and they include the front wall details. Is an "Engineered Tall Wall" a typically ballooned framed wall that is just signed off? What other option of there for the 10' ceiling height max in the building code? Thanks in advance for the help.

gcrank1
Member
# Posted: 1 May 2022 19:06
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Well, I guess if that is what the inspector says then find out from him? what needs to be done to make it acceptable.
The inspector's call is the only one that matters.

gedna002
Member
# Posted: 1 May 2022 20:13
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Thanks. Yeah, I got the "none of this is going to work start over vibe" from him. As I read more into the building code I think that balloon framed walls are suitable up to 21'. These plans are 22'. I'm just trying to get ahead of getting this set for the plan review. But, you're right, I need to give him a call. This exchange was over email.

ICC
Member
# Posted: 1 May 2022 20:24 - Edited by: ICC
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The engineered wall may look like a balloon framed wall on a drawing. However, it is more than just having an engineer apply his professional stamp. The wall would most likely have at least 4 LSL pieces of lumber used instead on standard sawn 2x lumber. LSL = laminated strand lumber. Kinda looks like thick OSB but probably uses different size flakes and more pressure when being manufactured.

LSL are engineered and come if different grades like sawn lumber does, but are much stiffer because of their higher and guaranteed modulus of elasticity. The structural engineer will use whatever wind data is specified for the area building code. The width and height of the wall plus the size and placement of the openings for doors and windows are taken into account. My guess is that most likely the engineer would break that window into three separate units. I have seen that a lot to allow placement of LSL framing members between the middle and end windows. Also maybe am LSL in or close to each corner joint. There are also engineered solutions for a wider window without columns between units. But that is an engineering decision. There is no cheap and easy solution in my experience.

The reasons for all this are mtriad, but front and foremost, if a wall does not have an upper floor or a ceiling within 10 feet of the lower floor there may be insufficient strength to the wall to resist inward flex and bending with wind. Especially when the studs from bottom to top are interrupted by a cutout for a window. Gable end walls are often one of the first failure points in high wind events.

The side walls will also need some method of resisting outward spreading forces from the rafters over that front room with the cathedral ceiling. Are there any wall to wall ties or cross-beams listed in the plans? Did the inspector say anything about that? Or another solution would be to use a center ridge beam, not a ridge board. That would require a load path down to the foundation to support that beam load which is half the weight of the roof, with snow and wind factored in. The other half of the load would go down through the side walls, split 50/50 [per side, to the foundation.

gedna002
Member
# Posted: 1 May 2022 21:06 - Edited by: gedna002
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Wow, thanks! That's a lot to digest but for now, yes, the plans do specify a ridge beam. Does the ridge beam need a direct path to the foundation at all points? Right now the beam mid-structure is uninterrupted (solid post). At the front, the beam is supported but it's not a direct path. There are windows with a 4x12 header. Without a post at the front, there still wouldn't be resistance to inward flex, correct? *Edit I'm re-reading your response. Windows need to be broken up. $$$. I probably need to find another solution.

ICC
Member
# Posted: 1 May 2022 21:39
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A direct path is not necessary if the alternate has been designed properly. Often the load will be transferred by a beam to two separated points.


Quoting: gedna002
Windows need to be broken up


Quoting: ICC
There are also engineered solutions for a wider window without columns between units.


Does not need to be broken into 3 sections. That is often done as a solution. But it may cost more. An engineer can come up with a variety of solutions. A good one should be able to cover a price range with no trouble. The one we used a lot would often supply a cheaper and better-looking solution.

gedna002
Member
# Posted: 1 May 2022 21:44
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Got it. Well, the plans include Beamcheck reports for all of the joists, beams, and headers. I'm wondering now how much the inspector looked at the things I sent.

gcrank1
Member
# Posted: 1 May 2022 22:05 - Edited by: gcrank1
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HaHa
Yeah, maybe he? just doesnt like the look....
Ive never had to jump thru those hoops but dont they have to be specific, if you ask, about what isnt acceptable and why?

MJH
Member
# Posted: 1 May 2022 22:32
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Which county are you in? Dealing with the inspector we've been dealing with in NE wisconsin has been a wild ride.

gedna002
Member
# Posted: 1 May 2022 22:40 - Edited by: gedna002
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Quoting: gcrank1
Ive never had to jump thru those hoops but dont they have to be specific, if you ask, about what isnt acceptable and why?


That's what I'm going to do. I think I worried too soon that it wouldn't work but now now I need more info.

Quoting: MJH
Which county are you in?

Douglas County

ICC
Member
# Posted: 1 May 2022 23:45
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It never hurts to ask questions, IMO. But do remember that his title is "inspector", not designer or anything else. The are required to provide what is wrong. Many will tell you what will satisfy the requirements. The code in WI is not the IRC which is used in most states. I have never worked there.

I do know the IRC does spell out many prescribed practices that will meet code. And in many sections there will be a phrase added that means if an engineer approves and stamps anything not specified in the code, that will be okay and approved by the permit department. But anything that deviates from code needs an engineers approval to be okay. There are some things I can do the calculations for, but I don't have an engineering degree or license, so that does not count.

When inspector disallows something, legally they must supply a valid reason and point to the section of code their decision is based upon. But that is all they must do. That do not have to provide a solution. Most are better than that. Inspectors also have a lot of leeway in the other direction. If they deem that some infraction is not all that important in a particular case they can let it slide by. And they are human, they can make errors in either direction.

However, when it comes to things like tall walls or missing rafter ties, inadequate fastener use, etc., that can be a structural safety issue and the code book may be more strictly followed. And IMO in those cases the book is probably a very good guide. OTOH, if the code violation is finding a staircase a fraction of an inch too narrow, that be overlooked as not a big deal.

Oh, I had meant to say in an earlier post that there are many places on the web that sell plans that have minor to major issues. Sometimes it might be because of code changes made since the plans were drawn. Sometimes the seller is not a licensed architect or engineer in any state. Some plans I have seen being sold to anyone from anywhere would only meet certain location specific rules. It is another case of buyer beware. Usually they all include a phrase that it is the responsibility of the buyer to determine the suitability of the plans for where they will be used.

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