Large Scale Central

Hadrie Board/backer

I don’t know where else to ask this so I will ask it here because I do want a review. For the bench work section of the layout which will be the yard and maybe also the wye area I want a flat hard surface that is weather resistant/proof. I was thinking of making this bench top out of trex decking or some other composite decking. But it is a very expensive product and I don’t want the rounded edges, I would want them flush fit. That means ripping each one. When looking at siding I see that Hardie makes a smooth fiber cement panel and also a stucco fiber cement panel. 4’X8’ sheet materiel. Its about the same price if not cheaper than exterior grade plywood. It is thinner and would need more bracing. But best of all is made to be weather resistant and rot resistant.

Has anyone used it for this or even making buildings for the layout.

(http://i234.photobucket.com/albums/ee259/smcgill_pics/Engine%20terminal%209_zpsfuwybx9m.jpg)

The grey floor is backer board. But it’s inside .

I thing Greg is also using but out in the weather.

It works for my purpose!

The cement board does work fine outdoors, painted or not, although painting at least the edges, provides some additional protection from the elements. It commonly comes in ½ and ¼ inch thicknesses. It needs little bracing if placed on the ground, but elevated, 12 to 16 inch bracing is a good idea to prevent cracking and/or breaking. Works very well for structure substructures. I used it for my outside storage shed with good results. It of course provides a very level and stable surface for switches, etc. Much more durable and weather resistant than PT plywood. Not particularly cheap.

I’ve got some under my town buildings, been outside for years-unpainted and doing fine. It’s the thinner stuff.

If it’s the Hardi-Backer board that’s got the squares embossed in it, don’t use it in contact with the ground.

There used to be a depot on top of that. The stuff deteriorated to the point where the depot just detached.

This stuff delaminates into three distinct (and very weak) layers with just a season or two of freeze/thaw. Also, stay away from a product called “Fiberock.” It, also, disintegrates after not too long a time in the elements. There’s other stuff (I don’t remember who makes it) that is more of a concrete with fiberglass mesh reinforcement which may work better.

Later,

K

If I’m not mistaken there are at least two distinct types of “backer board” one type is water resistant and is used behind tile walls/floors etc

the other is more a cement board as mentioned above and is mostly water proof. The type I used was smooth on one side and very rough texture on the other. sheet size was about 4X6 if I remember correctly. Used a 4 foot square section for the base/pit of a turntable that was out in the weather for 8 or 9 years with no problems at all.

Disclaimer: I did prime the sheet on all sides and edges with a high quality primer and had drains so water couldn’t stand in the pit. Also this was on raised benchwork so it had a chance to dry between wettings.

Rick

I used Hardiboard, the tile backer board, based on the advice of a friend. I made the floor and lower outer walls of my saw mill out of that stuff. The first spring that stuff was outside, it delaminated into little wafers. Same thing with my bridge abutments. But the bridge cap, that I made out of that stuff, held together just fine, year after year, until the tree rats (squirrels) gnawed the edges away, sharpening their teeth on it.

So if its in contact with the ground, it will become useless very quickly. If its up off of the ground, then you have a chance.

Have you given any thought to Sintra? Sintra is a PVC foam board that works well in outdoor applications.

Thanks for all the great experiences. The stuff I was thinking of is the cement stuff with fiberglass mesh in it. And I did ask about buildings but the main purpose here is for the bench work which will be above ground.

Steve,

I assume when your recommending Sintra your talking about for buildings.

Look at Ken Brunt’s thread on his raised benchwork. He uses a Sintra like PVC board product to support mesh and screen which holds dirt and/or ballast. You could use PVC boards the same way you would use Trex decking, but it has square edges. It too is very pricey. PVC board will weather very well and last a long time out doors. It does need to be supported well. Trex works with 16" centers, but I think you would need to be closer with PVC to avoid sag.

I plan to start building elevated this summer. In my job make a lot of PVC scrap that I can bring home as well as other weatherproof substrates and framing members. Still trying to decide how best to use what I can grab from the dumpster at work.

Ah I know the stuff I think your referring to. That is a distinct option.

Ouch that stuff is expensive. But would be a great idea. I will have to weight the cost of this stuff over the cement board and some exterior paint.

Doing some quick calculations that stuff would be very expensive to use in this way. I think the cement board would be a better way to go at least on my pocket book.

Wonder if It would give a good look if the cement board had a coat of foundation sealer applied (black tar stuff) and then sand applied to the wet tar to make it look more like earth. Then the tar would even further seal the cement.

Devon, is this the product you are referencing? It is Hardee Panel which is a 4x8 fiber cement panel.

If so, I have this product on one of my rental houses. Installed it 15 years ago and it looks just as good today as it did the day I put it up. It will require additional structural support, but will hold up to the elements well.

No, thats what I am going to side my house in though.

This is the stuff I was thinking of

I guess its not made by Hardie. I thought it was.

Devon, how expensive will the cement board be if you have to do it over.  "I can't afford to do it right, but I can afford to do it over."

Steve, isn’t that the American (corporate) way? Never enough time or money to do it right, but always enough to do it over.

That’s true Steve for sure. I would hope that the cement board elevated off the ground and then treaded with a sealer wouldn’t need to be done over. Cetrsiy the PVC wouldn’t need to be done over that’s for sure. I am still very much h considering the 1x3 PVC for the ladder for that. Very reason.

Devon,

The board in your picture is Durock Cement board. Not sure if is rated for Ground Contact.

I am not putting it on the ground. The yard will be the top of an elevated cabinet. The only real exposure to moisture or weather (not found in the air)will be the surface which I want to treat with a sealer.

But I would still be concerned that it will deteriorate, I know PVC won’t in my lifetime. But if this stuff will hold up in this situation then it is certainly cheaper than PVC. I like being frugal but like Steve says I can’t afford to do it over.

I went back and read my first post and I have even confused myself. Originally I was thinking house siding like Dan H. posted a picture of which is fiber cement. Then I switched to the cement board idea with the fiberglass mesh. I didn’t really convey that. I apologize for being ambiguous.

Devon, I don’t think the cement backer board will hold up over time. It certainly was not designed for exterior horizontal use. Also, it is meant to have a solid subsurface to rest on like a plywood subfloor. The PVC that Steve suggested will be there for almost forever. Have you considered using the method that Ken has used on his new elevated RR. Have you considered just pouring an elevated concrete slab? It would take a little work but it will also be there for a long time.