Alaska Cedar NLT Panels In Exterior Conditions?

[sgs114]

Hello,

I had posted about a bridge question I had earlier, and got some good suggestions as far as bridge deck. I was also looking into using Alaska Cedar NLT panels for the bridge deck. Researching NLT panels, it seems as though moisture content (wood swelling) is of quite concern. My environment is on a trail on the side of a mountain and would be quite exposed to rain and heavy snow, so I am wondering if this environment would be too harsh on the NLT panels even if they are made of Alaska Cedar. Steel would be more durable I am sure, but it is fairly remote, so I think installing these NLT panels would be considerably easier. Anyone have any input on Alaska Cedar NLT panels?

SGS

 

[SlideRuleEra]

1) Researching NLT panels, it seems as though moisture content (wood swelling) is of quite concern.
My environment is on a trail on the side of a mountain and would be quite exposed to rain and heavy snow...

2) Steel would be more durable I am sure, but it is fairly remote, so I think installing these NLT panels would be considerably easier.

1) Panels are only as good as the fasteners. Are galvanized or stainless steel nails used?

2) Based on what objective criteria? Weight? Size? Connectors?

http://www.SlideRuleEra.net

 

[dhengr]

Sgs114:
In an exterior application, with significant moisture, I would be worried about the nails rusting through at each joint btwn. laminations. Then, in fairly short order all you’ll have is a bunch of loose boards floating down the river, and large holes in your bridge deck. Take a look at some nails in any exterior joints, residential deck boards to joist, ledgers to the wall, any joint water can get into and not readily dry, and you’ll find rusty nails or screws immediately around the joint area (at that nail length location). While the nail at mid-thickness of the lumber is still in pretty good shape. And, I’ve seen decks fail because these fasteners rusted through. Furthermore, you probably want a deck with open joints in it, so that the deck drains well. Cedar 3x6’s or 4x6’s might be a better choice for decking and save all the nailing. Then, on top of that, put a couple, three/four wide 3x6 wear strips the length of the bridge, at the tire tracks. At the horiz. joints btwn. the deck boards and the main timber beams, apply some peel-n-stick, ‘ice and water guard’ tape to the top of the beams before laying down the deck. This stuff tends to seal the nail/screw holes into the top of the beams and helps the beams drain at that joint.