Question on floor decking

[Dennis]

Question came up earlier today by one of the engineers on floor decking. What products, OTHER THAN wood based or concrete, can be used for floor decking over joists?

Is there a plastic foam or composite material that anyone has hear of / used? Perhaps something used in Europe or Asia?

[<moo]

no

use plywood in residential and concrete in commercial

why the hell would you want to use foam for floors or plastic

are you building houses for Movie Studios so they can do a remake of the towering inferno?

Plywood can be made from new growth trees so there is no reason to not harvest it and use it

besides it will break down over years and biodegrade in landfills plastic wont

[DanG]

I know you said no concrete.

We used a cement board good for 100#/SF loading in 3/4" or 1" thickness. Used it on steel stud joists spanning 17&#39; as I recall. There was a requirement to buy in full bunk quantities. We used primarily for the fire rating.

Here is a link if you are interested:

______________________________ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[Bob Morrison]

If you are using wood joists why use anything other than wood for the sheathing?

If it&#39;s finished surface on top of wood sheathing you are after, then there might be fiberglass panels, steel sheets or other types of products available. Still don&#39;t know why you would want to though.

[Dennis]

That is interesting. I haden&#39;t heard of this amterial before. (And at 150 lbs a panel, it must be a real trick to lay in place.)

Thanks for your comments, Dennis

[Dennis]

Thanks Bob, it was just a hypothetical to discover if any unconventional products were being used.

There was talk a few years ago about the use of a plastic (or some alternative material - I can&#39;t remember now exactly what it was) composite material that had structural capabilities for both floor decking and exterior sheathing. But I haven&#39;t heard anything about it for some time now and thought I would put out a feeler to see if anyone else knew anything. (Could have been made out of seaweed for all I remember.)

Dennis

[Dennis]

Well OSB actually as plywood is too expensive. : ) Anyway it was just a hypothetical question.

The day may come when we may very well see plastics or paper composits or as floor decking. (After all, we now have cars that run on air - who knows?)

Thanks for your thoughts, Dennis

[Bob Morrison]

There are non-wood wall sheathing products, but none of these can be used on a floor. Plywood or OSB are still the least expensive products around for use as horizontal sheathing in residential and light frame commercial structures.

[Dennis]

Bob, I just ran across (released this month) a non-wood structural decking made from straw, and it has a PS-2 rating.

It&#39;s going to be made by Above Board Technologies, Inc., out of Saskatchewan.

According to the press release, it:

• performs at a structural equivalency to OSB,

• promotes a new way of harvesting the wheat straw utilizing the stripper header on the combine, which will save fuel costs, decrease time required to harvest grain, and increase the amount of straw left to be sold to the panel mills; *provides the wheat farmer with a marketplace to sell straw, which for the most part, is currently a waste product; and *is completely termite resistant, unlike OSB.

It&#39;s being referred to as Oriented Structural Straw Board (OSSB).

My how the world is changing. Next week, seaweed....... Dennis

[Bob Morrison]

From the document I can see that it does not yet have a PS-2 rating. For use as a replacement for OSB sheathing it will also need approval for use as structural sheathing in the US from ICC. Otherwise it does not have the horizontal shear capacity need for use in shear walls. There are several products on the market that can be used where wind loads govern the design, but they cannot be used where seismic governs.

Here in the Pacific NW, we get both wind and seismic!

[Wayne Whitney]

Can you comment on how a panel product could be adequate for resisting shear from wind loads but not from seismic loads? Is it an issue of load duration?

Thanks, Wayne

[Bob Morrison]

It&#39;s an issue of cyclic loading. The material around the fasteners starts to crush or become soft and the material no longer has the strength to resist the design forces. A classic example is GWB (sheetrock). It works fine for resisting wind loads, but is terrible in an earthquake.

Here&#39;s a link to a product I&#39;ve been keeping an eye on. Last year they did not have ICC certification to use this product in seismic zone D, but they have been testing and apparently now have that certification. If I can find a local dealer, then I may be adding this product to my specifications.

[Dennis]

As I delve deeper into this I&#39;m getting more and more amazed. Turns out that the ICC developed acceptance criteria for OSSB (OSB straw board) in 2005. I suppose we&#39;ll see plastic power-driven nails in the future. (After all they have cars that run on air now - smile)

If the product ends up having values similar to OSB, it could have an interesting future; particularly in the developing world. I can see China developing an OSB-type product based on bamboo. (At least that would allow the price of OSB to return to somewhere around normal.)

Personally, I don&#39;t a problem of using the board for resisting either wind or ground acceleration, as long as it&#39;s used within its parameters like any other diaphragm panel. (Considering non-wood panels, gypsum shear walls come to mind for example.)

Yea, the Pacific NW is geologically interesting. I visited Mt. St.Helens a few years ago; incredible forces of nature. Love visiting either Oregon (esp. Portland) or Washington (my son works in Seattle, but I don&#39;t get the opportunity to get out there as often as I like.) I could never live there, love the sun too much. My wife & I are going to retire in central Arizona in a few years. Love the desert even more.

Anyway, from a personal viewpoint, my clients range from seismic areas like Missouri & South Carolina to wind areas like Florida & OSB is still the flavor-of-choice of course, but who knows. There was a time when no one what ever consider using anything but plywood. In five years we very well see horizontal diaphragms and shear walls make from straw!

When I started this on a rant of "why not seaweed panels" and never really thought that I&#39;d find anything. Surprisingly, I found a whole ration of new ideas for products that we may very well see someday. (Ok, being no spring chicken, perhaps not me).

I just found a website on alternatives for concrete foundations. Outside of the usual wood pier, wood panel wall and the like, there&#39;s a considerable diversity of methods and products being touted. Maybe seaweed panels are not as ridiculous as I was attempting to be at first.

Take care, Dennis

[marson]

(At least that would allow

Might not be the best time to build a straw board plant...7/16 OSB is down to about 6 bucks a sheet in my neck of the woods.

[Dennis]

Wow. That&#39;s a far cry to what it was last spring.

Don&#39;t get me wrong, I&#39;m not a proponent of non-wood products, I simply find it extremely interesting that a deck made from non-wood products like straw is even feasible. A product considered as waste. I find it interesting as to what the world is coming to.

[Bob Morrison]

Many of these products are structural resin with some sort of fiber filler so that they can be installed with nails or screws. The trick is not what is is being used for the fiber filler, but the proper distribution of the fibers in the resin. The fibers must be the right shape and weight, or they don&#39;t distribute through the mix and then press into sheets properly.

[Dennis]

I&#39;ve seen a lot of those type products, but I wouldn&#39;t consider them as non-wood as they need the wood fiber for strength. (Actually I&#39;ve only read about them, never seen them used anywhere.)

The OSSB seems differnt however. According the the manufacturer, they "split the hollow plant stalks to maximize the surface area on the straw fibres. The increased surface area allows the individual fibres to bond when mixed with an isocyanate resin, which is then subjected to heat and pressure. This process causes the individual fibres to inter-weave, creating a panel equal in strength to wood based OSB products."

I haven&#39;t read what the nail holding values are, that would be a critical factor; of course.

In the future, the little piggy&#39;s house made out of straw may very well be the better one! Dennis

[Wayne Whitney]

The information on OSSB that Bob Morrison originally pointed to said that the product is not to be used as a nail base for siding.

Cheers, Wayne

[Dennis]

The info published by the manufacturer states it&#39;s going to be the equivalent to OSB. (Still in pilot plant.) (And there&#39;s an ICC spec on it as a structural board.)

(BTW, I was the >

[Wayne Whitney]

Sorry, my mistake, I was confusing the "Fiberbrace" Structural Wall Sheathing that Bob Morrison did reference (and which says it is not to be used as a nail base for siding) with the OSSB that you referenced.

Cheers, Wayne