Composite decking materials - Structural?

[JAE]

There are numerous companies out there (Trex) that provide composite decking materials for exterior decks. I've got a potential project where they want to use a composite to replace an existing wood deck (fire marshall demanding it be removed since it is flammable).

Most sites I've visited appear to deal with composite decking only and don't deal with spanning members, columns, etc. Are there non-flammable composite decks that would provide spanning capability? Anyone aware of anything like that?

 

[flash3780]

Your post got me curious, so I hunted around a bit. Have you seen this manufacturer?

http://www.american-plasticlumber.com

 

[MiketheEngineer]

Why is the fire marshal so upset? Unless this deck is HUGH. Wood is used ALL over the world as deck material and meets the codes as far as I know...

 

[JAE]

flash - thanks for the link. I hadn't seen that. However, the spans are very limited - a very low E value and about 1/2 the stress levels of regular wood.

Mike - Deck is part of a hospital - non-combustible construction - so the wood deck is a violation of the code.

 

[MikeHalloran]

I'd expect the limp recycled thermoplastic decking they carry at the lumberyard to burn pretty well.

How about the FRP grating that's sold for chemical plants?



Mike Halloran
Pembroke Pines, FL, USA

 

[firai]

I probably wouldn't choose a composite product when the main concern is fireproofing in a hospital. The flash points for such products are usually slightly higher than wood, but not by much (100-200deg F higher). The ASTM flame spread also typically falls into class C (the worst). Once temperatures reach the glass transition temperature, loss of strength rapidly ensues.

As such, I don't know of any product that meets your needs. If anyone else knows of a product like that, I'd love to hear about it. Good luck!

Structural Design Engineer
New York, NY

 

[msquared48]

Yoiur architect will love this, but what about extruded Aluminum shapes in the form of decking material?

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[Ron]

JAE..agree with Mike on the aluminum. It can be a bit expensive, but it works. Connections have to be design for temperature extremes 'cause aluminum moves all over the place when heated....here's a link to a decking company and another link to an architectural aluminum company that does a variety of aluminum structures....

Aluminum Decking

Aluminum Structures

 

[csd72]

have you looked at the possibility of treating it with flame retardent

 

[a2mfk]

Is this an exterior wood deck?

 

[JAE]

OK - now I get from the client that it will be framed with fire treated lumber and over-decked with composite decking. I think I'm good to go.

Thanks for the answers - appreciate it!