Q&A / 

Scissors Truss Design

Scissors Truss Design TIPS

Scissors = Vaulted Ceiling

A scissors truss is a really cool roof framing option. You not only get the speed of framing that you get with common trusses, but also the added benefits of an interior sloped ceiling.

The slope of the interior ceiling is one-half the slope of the outer roof.

For example, if you have a fairly steep 8:12-pitch roof outside, your inside vaulted ceiling pitch will be 4:12.

Those numbers stand for inches of rise per foot of run. In other words, the 8:12 means the roof goes up 8 inches for every horizontal foot it travels.

Special Software

The companies that fabricate the trusses use sophisticated software to design the trusses. You provide the span of the roof and the desired exterior roof pitch and the software does the rest.

You can ask the structural engineer at the truss fabrication plant if there is a way to increase the interior slope, but I doubt you'll get much more than one-half the slope of the exterior roof surface.

CLICK HERE to get FREE & FAST BIDS from carpenters who work with trusses all the time.

Partial Scissors

I think the motto of truss engineers is: If you can dream it, we can build it.

I say this because I've been to truss manufacturing plants and seen countless drawings for trusses of all different shapes.

A few years ago a new home being built near where I live in central New Hampshire had a unique truss that was a partial scissors.

The truss was a scissors for a short distance where it came up off the exterior walls and then the bottom chord flattened out until it approached the other exterior wall.

This truss was used in a large garage where the owner wanted a taller ceiling, but this truss could have just as easily been used indoor where a homeowner had a large room they wanted some sloped ceiling as well as flat in the same room.

Partial Scissors Truss Video

Watch this video to see the truss I saw at that new home site.

This scissors truss provides support , while providing a vaulted interior.

This scissors truss provides support , while providing a vaulted interior.

Remember, the closer you get to the actual exterior slope, you negate the impact of the interior truss components. A true cathedral ceiling using regular rafters mimics the actual roof slope because each rafter becomes a large beam.

Mix & Match

Remember you can mix and match trusses! Over part of your home you can have scissors trusses, while over another part you can have common ones and over the garage you can have attic or storage trusses.

The cool thing is that from the outside no one would ever know since the exterior roof slope of all the trusses is identical. Ask your builder to explore all truss options including attic trusses and storage trusses!

CLICK HERE to read about attic trusses.

CLICK HERE to read about storage trusses.

CLICK HERE to get FREE & FAST BIDS from carpenters who work with trusses all the time.

Column B348


9 Responses to Scissors Truss Design

  1. I'm adding an addition to a ranch house which has scissor trusses throughout. I'd like to add a saddle to one section of scissor trusses without adding a bottom chord.

    Is this possible?

Leave a Reply

You have to agree to the comment policy.