Each building has unique characteristics that require special attention. Hold-downs, shear walls, blocking, backing, special stud heights, and posts are some of the more common miscellaneous framing items. The framing language for these framing items is not well-defined because the operations frequently change and the same ones are not always used. The Miscellaneous Layout
Language Chart on the next page gives you an idea of how these framing tasks can be communicated.
Hold-downs are probably the most difficult to mark correctly. They vary from location to location and require different studs or posts for connecting.
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Top plate tacked to bottom plate hanging over edge of concrete for layout
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Offset backer
Crayon marked
There are also different types of hold-downs, and each manufacturer has its own identification system. There are, however, four basic styles of hold-downs that you need to show in your wall layout.
1. Basic hold-down: bolts, nails, or screws to the hold-down post or studs. This type is typically attached to an anchor bolt in the foundation or bolted to an all-thread rod that is connected to a hold-down in the wall below. (See “HoldDowns with Floor Between" illustration.)
2. Hold-down already embedded in the concrete, which needs only to be attached to the wall. (See “Hold-Down in Concrete" illustration.)
3. Strap used to connect the top of one wall to the bottom of the wall above. (See “Strap Wall to Wall" illustration.)
4. Hold-down that is continuous between all floors from the foundation to the top floor. (See “Hold-Down, Continuous" illustration.)
The difficulty in laying out for hold-downs is knowing what to write on the plates so that the requirement will be easily understood. The best thing to do is to explain to all framers at the beginning of each job what symbols you are using to indicate hold-downs. Use the same language when possible at different jobs. The most common symbol for hold-downs is HD, followed by the number representing the size of the hold-down—for example, HD2 or HD5.
When you are laying out for hold-downs, it’s important to get the layout in the right location. Since the purpose of a hold-down is to connect the building to the foundation, the hold-downs must
line up with the anchor bolt in the foundation below them. Hold-downs are typically found at the end of shear walls. Engineers sometimes position hold-downs attached to posts at the ends of walls or within a specific distance from the ends of walls. If that information is not specified, keep the hold-down as close to the end of the wall as possible. If the hold-down anchor bolt is already in the concrete, then you can only position it in two locations—one on either side of the hold-down anchor bolt. (See “Hold-Down Either Direction" illustration.)
If the epoxy system is specified for installing the anchor bolts later, you have more options. A good rule of thumb is to keep the hold-down within one
foot of the end of the wall. However, the shorter the wall, the closer the hold-down should be to the ends of the wall.
When laying out for a hold-down, you want the studs or post to be in the correct position in relation to the anchor bolt or hold-down in the wall.
A good way to make sure the distance from the studs to the anchor bolt is correct is to use one of your hold-downs to mark the pattern and location of the studs or post. (See “Hold-Down as Pattern" photo.) If you do not have a hold-down available for this purpose, you can use the manufacturer’s hardware catalog to find the distance from the anchor bolt to the studs.
When you are laying out for the hold-downs on an upper floor, it is helpful to mark the location of the hole to be drilled in the plate and the floor. You have to locate the hole anyway to lay out the studs. By marking its location, you are saving someone else from having to locate it again. It is easiest to go ahead and drill the holes through the floor then, before the walls are built. These holes can be oversized to make alignment easier.
Shear walls have unique characteristics, but the most common information a framer needs to know about them is the type of sheathing, the edge nail spacing, and the nail spacing for nailing of the bottom plate. This information can usually be found in a shear wall schedule in the plans. The sheathing used is typically either plywood or OSB, commonly identified as "W," or gypsum, identified as "G." The edge nailing is designated as a number after the W
or G, and the floor nailing as a number before the W or G. An example could be "6W4," meaning that the bottom plate is nailed at 6” on center, the sheathing is plywood, and the edge nailing is 4” on center. The language for shear walls can be written on the plates with the other language, but it is best to also write it on the top of the bottom plate. That way, when you get around to nailing the wall down, the nailing pattern will still be visible.
