LVL for covered porch is possible?

[Localeng]

Dear Engineering folks,
LVL is NOT suitable for the exterior application according to the manufacturer, Weyerhaeuser.
Beams of a 1covered porch that have a covering and waterproofing roof, which is very limited chance of exposing to the weather, can use LVL?
Or, this application is still considered as an 'exterior application' and LVL should not be used?

Thanks for your thought, idea and tips on this issue.

 

[jayrod12]

If the building envelope encapsulates the beam, i.e. there is protection from the exterior humidity and precipitation on all sides, then sure go ahead.

Otherwise, do not do this. Even if it doesn't see direct precipitation, the humidity in the outside air will cause issues. You will end up having the same issues as engineered wood in poorly ventilated crawlspaces.

 

[jjl317]

Any reason you are not considering a Parallam Plus PSL (or similar), which are rated for exterior use?

 

[Localeng]

jayrod12 (Structural)
Thank you for the recommendation.
Did 'Encapsulate the beam' mean wrapping Tyvek around entire beam, covering the beam, or something else?

 

[Localeng]

jjl317 (Civil/Environmental)
There are many situations that I need to use LVLs.
- Cantilevered joists or beam for balcony
- Reinforcing existing joists or beam with a limited depth due to existing condition
- If a beam supports 4' cantilever for balcony and 8' spanning into the interior, only 4' cantilever will be treated or entire span of 12' will be treated?

 

[jayrod12]

Technically yes, essentially though you need to ensure that no moisture,and minimal humidity gets to the beam.