About this Timber Truss
The king truss is probably the most common used style of exposed timber trusses. There is an explanation for this- Timeless Geometric Beauty! It is a cross cultural gem that can really be adapted to fit any style.
You can use the arched bottom timbers and curved webs increase the elegance factor. The Timber King Truss works best with Rustic, Traditional, Classic, and Euro Timber styles. Although I’ve had the opportunity to work with an old style timber king trusses on a restoration project which used an iron rod as the king post. While this project was very rustic, this king truss variation could easily compliment a modern style well.
A common mistake you’ll want to avoid if you choose a king truss style, is positioning the angle of the webs 90 degrees or perpendicular to the sloped/top beams. This is a mistake we see repeated often, probably because it seems easy and natural to align the webs at right angles to the top cords, but it really kills the balance- the center of the truss will appear pinched or cramped, especially so with the lower pitched trusses.
Note: If the webs are eliminated, it is still a king truss, as it utilizes a center king post.
I believe it is better to align the webs by eye to achieve the best balance- the same principal applies when you are deciding how much arch to apply or how much to raise the bottom horizontal truss member if your criteria so dictates- you will be working with factors such as wall height, room volume, truss spacing and roof slope to arrive at the best decision for your timber truss.
Regarding load bearing capacity, it is relatively easy to span 30’ with timber king trusses spaced 12’ apart. Certain king truss joinery is achievable at 30’ without hidden metal connectors to address the tension loading. But, timber king trusses spaced 20’ apart, spanning 40’ are significantly more difficult, still achievable.