A few questions on advanced framing strategies
Getting ready to start a house and will be using advanced/OVE framing techniques. 2×6 wall with 1” DOW SIS sheathing. Seems like all of the published literature on advanced framing always shows headers attached to the king studs with header hangers in lieu of a jack stud. I am thinking of moving the header up into the floor system (Band Joist) above and not even have a header directly above the window. Can hang the second floor joists on the hanger if there is not enough room on the 2×6 plate – on the second floor, the header can be up at the ceiling joist band. Seems like a no brainer – will allow more room for insulation. We already remove the headers in non load bearing walls so why not remove it in the bearing walls as well. Anyone have any reasons why this would not be a good idea?
Insulated headers – seems like everyone has different opinion on this – have seen the rigid foam used as the insulation on the inside, outside and the middle of the header. I would think putting it in the middle would compromise the strength of the header. Seems to me like it makes the most sense to put it on the exterior. Anyone have any pros or cons of the different locations?
我使用过高级框架的最后几栋房屋是砖。目前的房屋正处于壁板状态，因此需要考虑阻止/磨砂以进行外部装饰，并适当地固定。似乎在每个角落和每个窗口周围都需要在侧面安装2×4的侧面（如果修剪不太宽，则可能会撕成两半）才能用作钉子。似乎我们将不得不这样做来撤回许多我们试图节省的木材。有人知道更好的方法吗？
Not sure if it matters for this topic – but in NC – 3A
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
答复
Danny,
您可以将带托梁用作标题，在某些情况下，单个乐队成员足以承载负载，但是您必须进行工程。
Floor joists perpendicular to header/bands have to be on hangers so that their tributary floor load is carried on the header and not the top plate. Since the hangers will need to be below the bottom plane of the joists, you will want to place the header/band to the inside of the top plate. You can either place a secondary header member on the inside with the primary continuous band in the normal position on the outside (with foam in between) or move the entire band joist to the inside, hang all joists in hangers and add additional foam outside the band. Or you can leave the band joist on the outside of plate and notch the joists over the windows to make room for hangers.
大多数奥维建筑依赖外壳提供nailing for exterior trim and siding ends, but with SIS you'll probably need solid wood nailbase and longer siding/trim nails to get proper embedment.
Since the minimalist framing connections of the OVE system, I believe, rely to some extent on the sheathing to help tie it all together and provide additional structural support, be sure to follow SIS nailing guidelines around window and door openings (3" oc nailing at edges).
Do you know the thickness of the structural material on the SIS panel and what it's made from? Dow seems a little secretive about that.
关于将标题移至轮辋板，我经常想知道同样的事情。标头的整个点是将窗户周围的负载转移到支撑螺柱。为什么要有1 1/2英寸的轮辋板只需将双重标头放置在下方。相对于将两个零件放在下部？
A similar notion I had, while admittedly adding cost to the initial construction, would allow for greater flexibility and easier expansion/remodeling and that is to double the entire rim board along the load bearing walls. It should act as a continuous header across the load bearing wall. Thus replacing the need for structural window or door headers entirely, except for very large openings. This would allow for future owners to easily reconfigure windows and doors as needed and/or desired without extensive structural reconfiguration.
Robert beat me to a better explanation
The reason we use headers below the top plate for door and window openings in walls that bear floor loads is because the top plate(s) is supporting the ends of the joists - the end-grain nails from band to joist are not sufficient to transfer those loads.
So a band joist can serve as a header only if the floor joist loads are transfered to the band joist on hangers. This complicates floor construction and may create drywall problems, and doubling the entire band joist makes thermal bridging more problematic while also requiring more lumber than headers would.
Thanks guys - seemed like a simple idea and I didn't think I had invented it, but not sure how this has never been on any advanced framing details I have ever seen.
罗伯特（Robert） - 我不确定它是由什么组成的，但让我想起了旧的热层产品。一段时间没有使用过它，但据我所知，它可能是1/4英寸厚的。我第一次使用它的结构性有点学习。在安装后实际的刚性程度。
JLC有一个关于SIS的线程，有人将其发布有关结构材料的厚度：
“这些东西是隔热层层压到薄压缩纤维板上的。隔热材料是封闭的多丝氰尿布酸盐，并被视为蒸气延迟器和空气不渗透。SIS使用的板仅为.113英寸。厚度为.113英寸。只有.135厚。”
是的 - 大约1/8“可能更近 - 它们确实有1/2英寸的产品，因此更有意义。
我将使用SIS面板开始一个新房子，我想知道邮编墙和非结构性泡沫板与结构泡沫面板（SIS）之间的成本和性能差异是多少。
Even interior drywall is credited with a minimum of 150 lbs of lateral resistance per linear foot, so it's all cumulative. But I think it makes more sense to use a structural sheathing that is also a nailbase for trim and siding, then deal with insulation and weather barrier separately.
Almost without exception, anything designed to perform several functions performs none of them as well as a single-function element.
Why hasn't anyone talked about the permeability of SIS?
According to Dow's website:
As tested per ASTM E96, Procedure A, the perm rating of STYROFOAM™ SIS™Brand Structural Insulated Sheathing is approximately 0.03 perms.
A Class I vapor retarder with an R-value of only 3-5.5 is concerning.
因为问题是关于标题的。
Oh, I thought the thread was about "A few questions on advanced framing strategies" using a 2x6 wall and SIS as sheathing.
艾伦（Allen） - 我以前曾看过邮政系统，并且可能是结构性护套，但我选择了道琼斯指数（Dow sis）进行额外的r值和热折断，并使墙壁略微降低。有了2x6的墙，密集的隔热材料和1“刚性泡沫 - 我可以得到R -28，在这里我们的代码最低限度的两倍以上。两家制造商都说它们可以用作WRB - 但我个人不想依靠磁带是我的WRB，在结构的寿命中，因此从这种意义上考虑它们相等。使用两种产品，我都会在它们的顶部安装毛毡或房屋包装。两种产品均与我所知一样的空气屏障。
布雷特（Brett） - 在我第一次使用Dow SIS之前，我担心自己的墙壁无法干燥，我们在这个论坛上进行了讨论（一年多以前） - 我会看看是否可以找到它。在混合混合潮湿的气候下，太阳能蒸气驱动是有问题的力量，低渗透率将有助于防止该问题。使用良好的HVAC系统和适当的通风，对内部的干燥不应该是问题。
Shear strength of dissimilar materials isn't necessarily cumulative. It depends on stiffness, the stress vs. strain behavior of each material. The most elastic material can end up carrying all the load after the less elastic materials have reached their limits and failed. Thus, at the limits, gyp board will crack and carry no load, leaving plywood to carry the entire load.
在这一点上寻找一些备份，似乎有关此方面的规则最近在IBC下放松了，只能抵抗风负载。
IRC Bracing Methods, Relevant Test Data, and Recommended Design Values for Wind Bracing Analysis of Conventional Wood-Frame Homes
Prepared by Jay H. Crandell, P.E.
Prepared for ICC Ad Hoc Committee on Wall Bracing
Construction Requirements for IRC 2006 Bracing Methods (R602.10.3)
Minimum Interior Finish (inside face of braced wall)
•½“石膏墙
• Vertical or horizontal unblocked installation
• 8”oc nail spacing or alternatively pairs of nails at 12”oc; or 12”oc screw spacing for 24”oc stud spacing or 16”oc screw
Method 1 – let in bracing
基于仅使用GWB的类似墙的测试（稍后解决），仅使用1x4支撑，并且两者结合在一起，似乎出于加性目的，GWB提供了约250 plf（Ultimate），而Brace则提供约1,500磅（Ultimate）（Ultimate）结合。因此，作为代表性的完全侵蚀的1x4方法1终极剪切强度值（包括½英寸GWB内部饰面）可以确定如下：250 plf x 8 ft + 1,500 lbs/brace/brace = 3,500 lbs = 3,500 lbs每方法1撑杆（终极）。
Method 4 – fiberboard sheathing
As before, it appears that the strength of the GWB interior finish is additive and, thus, a characteristic ultimate shear value could be determined as follows: 500 plf (fiberboard) + 250 plf (GWB) = 750 plf.
方法5 - 石膏护套
Two-sided Applications:
• GWB (4”/8” fastening per gypsum sheathing) + GWB (8”/8” fastening per finish)
Ultimate shear value = 415 plf + 250 plf = 665 plf
415 PLF的值少于文献中报道的值，但它促进了一种添加剂方法，从而导致构造的总剪切值，这通常与测试数据一致
布雷特 - 以前的问答您可能会发现有趣：
//m.etiketa4.com/community/forum/green-building-techniques/14255/exterior-vapor-barrier-ok-exterior-mixed-climate
你好，专业人士。
I'm bumping this thread, which began with a headers discussion, because I'm a couple of weeks away from installing a window in 12" concrete block in my basement, right up under the rim joist. It'll be a new opening, and I'd like to size the header properly so I can also insulate well. I'm intending to do the install (but not cut the hole) myself. The person cutting the hole normally does the installs too, and he says he normally puts *two* 4x6 posts in as a header. I'd like to be able to balance safety and insulation a little bit better than that.
有特别的减肥注意事项installing in concrete block that I need to be aware of, even if I'm right up under the rim joist? Because apart from that detail, I don't think there's a lot of weight for me to worry about. The span isn't crazy--it's 33". This wall, gable end, is perpendicular to the joists, but the wall that the center beam actually rests on is a bumpout--parallel to this wall in which I'm putting the opening, but not the same wall. And in terms of the rest of the load above, the second story and the roof bear only on the exterior walls and not on the center beam. So, I don't think there's an exceptional amount of weight above this proposed window opening.
So how do I calculate or closely approximate how large of a header I'll need under these conditions, but not drastically oversize it? Even if I did a single 4x6 header and matched the depth of the sides to that, considering I'm in 12" block, that'd still give me a remaining 6" of extra insulating room before I even get to the interior face of the block wall, which sounds fine to me. Fair? Still drastic? Or insufficient?