Guide
Heavy timber connectors: sizes, steel, bolts, and finish
Our post caps, post bases, joist hangers, and angle brackets are made to the sizes you enter. This guide covers what they have in common: how to measure a timber, the steel, the holes, the bolt spacing our configurators enforce, finish, shipping, and load ratings. What is particular to one part is on that part's page.
01 Sizes
Nominal vs. actual size: measuring your timbers
Enter the size your timber really is, not the size it's called. Lumber is sold by a nominal size, which is a name. A surfaced timber is smaller than its name, and a rough-sawn timber is close to its full size but varies from mill to mill.
| Called | Surfaced, typically | Rough-sawn |
|---|---|---|
| 2x8 | 1 1/2" x 7 1/4" | About 2" x 8" |
| 4x4 | 3 1/2" x 3 1/2" | About 4" x 4" |
| 4x8 | 3 1/2" x 7 1/4" | About 4" x 8" |
| 6x6 | 5 1/2" x 5 1/2" | About 6" x 6" |
| 8x8 | 7 1/2" x 7 1/2" | About 8" x 8" |
| 10x10 | 9 1/2" x 9 1/2" | About 10" x 10" |
| 12x12 | 11 1/2" x 11 1/2" | About 12" x 12" |
Treat the table as a starting point. Measure the timbers you have, where the connector goes, and enter what you measure. If they haven't arrived, ask the mill or the lumberyard for the actual size.
Don't add clearance of your own. Every pocket is cut 1/16" larger than the size you enter, so the timber slides in.
02 Steel
Steel and how the parts are made
Post caps, post bases, and joist hangers are 3/16" A36 steel plate. Each plate is laser cut, and the plates are welded together in our ISO 9001:2015 certified shop in Texas. Angle brackets are 1/4" A36 plate, laser cut and bent to 90° in a press brake, with no welds.
Every configured part is made to order, so check your sizes before you order.
03 Holes
Holes and fasteners
You choose the fastener's diameter in the configurator, in 1/16" steps. Every hole is cut 1/16" larger than that, so the fastener goes in easily.
- Post caps: 3/16" to 1"
- Post base: 3/16" to 1" for the post bolts, and 1/2" to 1" for the anchor
- Joist hangers: 1/4" to 5/8"
- Custom bracket: 1/4" to 3/4"
The caps, bases, and brackets open at 5/8", a size that is strong, inexpensive, and easy to find. The hangers open at 3/8".
Fasteners aren't included. The kind of fastener (a through bolt, a lag screw, or a structural screw), its length, and how many your loads need are for your engineer or your building official to say.
04 Bolts
Bolt end distance: the 3 1/2 diameter rule
A bolt too close to the end of a timber can split it. The National Design Specification for Wood Construction (NDS), the standard that U.S. building codes point to for wood, sets how far a bolt must be from a timber's end, counted in bolt diameters.
Our configurators hold bolts to the NDS's reduced end distance: at least 3 1/2 bolt diameters. That is 2 3/16" for a 5/8" bolt, 2 5/8" for a 3/4" bolt, and 3 1/2" for a 1" bolt. Choose a larger bolt, and the configurator asks for a longer strap, a longer saddle, or a taller base.
- Post caps: the strap bolts, measured from the top of the post. On corner and cross caps, also the second beam's bolts, measured from that beam's end.
- Post base: the post bolts, measured from the bottom of the post.
- Angle brackets: the holes stay 4 bolt diameters from the bend.
- Joist hangers: no end distance rule.
"Reduced" matters. It is the least the NDS allows, and at that distance the NDS also reduces what the bolt can be counted on to carry. Treat it as a floor, not a design. The configurators don't check edge distance, bolt spacing, or your loads. For those, ask an engineer.
05 Finish
Finish: bare steel, powder coat, or galvanizing
Parts ship as bare steel unless you add a finish. Bare mild steel rusts, so expect some surface rust. In most cases you can apply your own finish right over it, or take it off first with steel wool or sandpaper.
Matte black powder coat can be added in the cart. Our powder is a urethane polyester rated for exterior use: a smooth, low-sheen black that holds its color and sheen well outdoors. If the coating gets chipped during installation, touch it up with matte black paint so rust doesn't start there. For coastal or constantly wet locations, ask about galvanizing through the quote form. Need to match our black on other metalwork? Ask, and we'll send the powder's maker and product number.
Galvanizing is by quote, and it adds substantially to the lead time.
06 Shipping
Shipping and lead time
Shipping is free in the lower 48 states. Each configurator shows how soon its part ships, and the cart shows the current lead time for your order. Powder coating adds time. Lead time runs from your order to the day it leaves our shop.
07 Engineering
Load ratings
We don't publish load ratings for these connectors, and we haven't had them tested or evaluated. If your project needs rated capacities, or a permit calls for an engineer's stamp, have your engineer review the design and its fasteners. Give them:
- The part's dimensions, from the configurator's 3D drawing and your cart.
- The steel: 3/16" A36 plate, or 1/4" for angle brackets.
- The hole size and where the holes are, from the part's page.
- Your timbers' sizes and species, and the fasteners you plan to use.
If your engineer needs something else, contact us.
Ready to design a part? See our post caps and post bases, joist hangers, and angle brackets.