# How far can a parallel chord truss span?

## How far can a parallel chord truss span?

Scissor truss slope differentials between top and bottom chords must be greater than or equal to 2/12 ▪ Maximum span to depth ratio is 24 for parallel chord roof trusses (For example, a 24” deep parallel chord roof truss should not exceed a span of 48′).

## What are the advantages of parallel chord trusses?

Parallel chord trusses, also called girder trusses, are often used to support traditional trusses, rafters or purlins. They are extremely strong, so they can often span longer distances than traditional trusses. They are a good solution when trying to span a distance without needing a central supporting post.

**What is the span between roof trusses?**

Roof trusses should be 24” apart, on center. Trusses are allowed to be closer together, at either 12” or 16” on center, but building codes allow for 24” on center spacing without using heavier duty fasteners for truss to wall connections.

**How thick is a parallel chord truss?**

In low or no snow load areas, the trusses will be about an inch deep, for every foot of truss span, with a minimum thickness of about two feet. This thickness results in a loss of clear height at the eave of the building, which is going to reduce the headroom or useable space along the sides of the space.

### How far can a floor truss span?

A floor truss can be designed to span 30 or more feet with ease. The truss manufacturer can build them so strong that there’s no bounce to the floor at all. This comes in handy if you desire a tile floor.

### How do you calculate spacing between trusses?

For economic spacing of roof trusses, the cost of truss should be equal to twice the cost of purlins +the cost of roof covering. As a guide the spacing of the roof trusses can be kept : ¼ of span upto 15.0m. 1/5 of span upto 15m to 30m.

**What is the maximum span for roof trusses in feet?**

Max. Live Load 20 lbs/ft2 (956 N/m2)

Maximum Span (ft – in) | ||
---|---|---|

Nominal Size (inches) | Rafter Spacing, Center to Center, OC (inches) | Lumber Grade |

2 x 10 | 12 | 27′ – 6” |

16 | 25′ | |

24 | 20′ – 9” |

**How far can 2×4 floor trusses span?**

A 2×4 can span a maximum of 6′ 7” when spaced 16” apart and used as a floor or deck joist. When used as a ceiling joist or a roof rafter, a 2×4 can span up to 7′ 3” spaced at 16”, and 6′ 4” when spaced 24” apart. Due to the small spans of 2x4s, they often are not used in horizontal load-bearing capacities.

## What is a parallel chord truss?

A parallel chord truss is made up of two chords, one on top and one on the bottom, separated by webs—diagonal and vertical pieces that span the entire length of the truss. What Is a Parallel Chord Truss Used For?

## What are the dimensions of a roof truss span?

Roof Truss Span Tables NOTES: These overall spans are based on NDS‘01 with 4″ nominal bearing each end, 24″ o.c.spacing, a live load deflection limited to L/240maximum and use lumber properties as follows:2×4 f =2000 psi f =1100 psi E=1.8×10 2x6f =1750 6

**What is a scissors truss?**

As a scissors truss, the slope of the top chord again follows the slope of the bottom chord, with both chords having a peak at the center of the truss. There are some limitations. As with most roof trusses, there exists a limitation on what can be manufactured and shipped down the highway.

**Where to put attic space with parallel chord trusses?**

I assume the former; in that case, with parallel chord trusses I’ve always included an attic space in the top half or third of the span. The bottom chord of the attic portion provides most or all of the resistance to spreading. If you want a fully vaulted ceiling you may need to use deep trusses, or change to scissor trusses.