Need beam size to support 16 ft scissor trusses on 22 ft span.
#1
03-03-14, 05:53 PM
Need beam size to support 16 ft scissor trusses on 22 ft span.
Building a gable end roof over a backyard patio. Want to use 16 ft scissor trusses. What size beam can I use to support the trusses? Will tie beam into house at one end and support other end of beam with post on footer. Want to span 22 ft without having to use a center support post? Is there a difference between glulam beams, microlam beams and LVL beams? Can I span 22 ft without a center support post?
#2
03-03-14, 06:21 PM
All the types of beams you name are basically the same, some of different manufacturers. Laminated Veneer Lumber in 11 1/4" height, doubled can span 22' without center support. You should have a structural engineer determine the weight that will be placed on this beam to see if it falls into support parameters.
#3
03-04-14, 01:06 AM
Member
Tying the beam into the end of the house could prove to be the scary part. Most typical exterior residential walls are not designed to support significant externally-applied loads.
That structural engineer is your friend.
That structural engineer is your friend.
#5
03-04-14, 01:35 PM
Member
For the record: Glulam and LVL are not the same. Two entirely different products, intended for different applications. That's a plain fact, not an opinion.
Glulam beams are composed of relatively thick, stress-rated planks or laminations (but less than 2" thick), glued together under pressure with all grains essentially parallel, along their horizontal planes. Higher-strength planks are typically located at higher-stress locations (either at the top or bottom of a given beam), while lesser-grade laminations are located closer to the interiors where they won't impact the overall strength of the member. Such members are typically built for exposed, long span, commercial applications, and can also be curved during the glue-up process, making them particularly attractive architecturally. With the correct glue, they can be suitable for exterior use, but are far more commonly used at interior locations.
Laminated veneer lumber (LVL), on the other hand, consists of large, thin sheets of veneer, bonded together under pressure in a vertical orientation. They are commonly used in residential and light commercial construction, for shorter span structural applications. Member size, and resulting load capacity, can be increased by bolting several identical pieces together. They are typically used only for interior locations, where they are not exposed but rather usually covered by sheetrock.
Glulam beams are composed of relatively thick, stress-rated planks or laminations (but less than 2" thick), glued together under pressure with all grains essentially parallel, along their horizontal planes. Higher-strength planks are typically located at higher-stress locations (either at the top or bottom of a given beam), while lesser-grade laminations are located closer to the interiors where they won't impact the overall strength of the member. Such members are typically built for exposed, long span, commercial applications, and can also be curved during the glue-up process, making them particularly attractive architecturally. With the correct glue, they can be suitable for exterior use, but are far more commonly used at interior locations.
Laminated veneer lumber (LVL), on the other hand, consists of large, thin sheets of veneer, bonded together under pressure in a vertical orientation. They are commonly used in residential and light commercial construction, for shorter span structural applications. Member size, and resulting load capacity, can be increased by bolting several identical pieces together. They are typically used only for interior locations, where they are not exposed but rather usually covered by sheetrock.
