Floor Trusses

Editor's Message: Getting in on the Ground Floor

One of the most significant benefits of SBC Magazine’s new online polling approach is it gives component manufacturers (CMs) a glimpse into how their business model and/or local market compares to the industry as a whole. 

A Clearer Path

Open web trusses are the ideal match with a sprinkler system, maximizing use of space and making installation easy.

Deflection Limits for Floor Trusses - Educational Program

This research report will focus on manufacturer or trade association deflection requirements for a number of floor topping/covering related products where deflection requirements may impact serviceability.

Lumber Design Values

No matter the species, component manufacturers (CMs) purchase and rely on the accuracy and reliability of many different lumber design properties, including: bending (Fb); shear parallel to grain (Fv), compression perpendicular to grain (Fc^), compression parallel to grain (Fc), tension parallel to grain (Ft), and modulus of elasticity (E and Emin).

Chase Placement In Floor Trusses

Question: 

Is there a general rule of thumb to follow on chase placement within a top-chord bearing floor truss? In other words, how close to the bearing point of the truss can the chase occur?

Lumber Grades In Truss Design

Question: 

In truss manufacturing, can hemlock, fir and spruce be used instead of Douglas Fir/Larch? What grades can be used: Structural Light Framing (Select Structural through #3) only, or Light Framing (Construction through Utility) as well?

Penetration Of Fire Walls

Question: 

Can a roof truss penetrate a one-hr. tenant separation wall without having a one-hr. rated ceiling? The building official insists that the 2x4 chords are combustible and nullify the integrity of the one-hr. rated partition that is constructed in an attic above an 8 in. C.M.U. bearing wall. The partition consists of gypsum board attached to 2 x 4 stud framing. The building official insists that a ledger must be attached through the gypsum board to support the trusses each side of the wall. This is almost saying that any rated assembly must have bearing only on other rated assemblies.

Truss History

Question: 

How long has the truss industry been around and where did it start?

Owner Assurance

Question: 

As the owner for a building designed to have metal plate wood trusses, what documentation should I receive to be assured that the manufactured wood trusses delivered to the site have indeed been manufactured at a licensed and registered wood truss manufacturer under the required written quality control procedures?

Determining Truss Manufacturer From Stamps On Lumber

Question: 

I'm trying to find out who the truss manufacturer was that built the trusses in my home. I was told that there is usually a stamp on the side of the bottom chord. All I found was “2400F 2.0E.” What am I looking for? The other chords only have material stamps. Can you tell me what kind of information I should be looking for to find out who the manufacturer was?