Bricks, Masonry, Asphalt and Concrete - how to make a decrative cement slab

I saw a molded plastic form that looked like cement 30" x 40" with a palm leaf in it - of course it was fairly light weight. I would like to make a similar type item out of cement or some lightweight weather proof material that I can use to cover the septic tank in the yard - that way I could plant around it and still be able to access the tank in the future - Is there a light weight cement - do I need to put some sort of mesh or wire in the slab to bind it together? suggestions please

http://www.gardenmolds.com/pages/resources/foamcore.html

I think this might be what you are looking for. :)
Peg

this is a good site - but I'm looking for a larger size and info for free not the actual mold - I figure I can free form something and decorate myself - I just don't want the final product to fall apart or be too heavy to move - Thanks again

Why do you want to cover the septic tank? The only thing that should cover a septic tank is dirt and grass. Don't even think about planting anything else around it. That will lead to problems.

that's the point - I don't want a permanent cover - rather something I can move - If I plant grass or ground cover I'll have to dig it all up to access the tank. If I can duplicate a light enough decrative stone - I can move it without diging up the yard and it will look nice. I'm looking for a natural look. :thinker:

I don't know what you mean by "lightweight", but the term lightweight concrete refers to a mix using hadite instead of regular stone aggregate. It does weigh a bit less, but not enough that it would work for your application.
Regular concrete weighs about 18 lbs per square foot at 1 1/2 inches thick. Lightweight weighs about 12 to 15 lbs per square foot at that thickness. I don't know how thick youre planning on making your item, but if it is too thin it will crack and break apart, and if it is too thick it will be too heavy to move.
Why not just buy a birdbath to set on the septic lid, and put down landscape cloth or plastic and mulch around it. Then if you have to access the tank, you can easily move the stuff out of the way and back again.

Perfect answer - I like it - a birdbath would fit the land scape and easily manageable - The cement you mentioned that is lighter weight - where do you buy it - just for curiosity sake :o

Although this link is to how to make a planter, the lightweight construction process of hypertufa will enable you to make something light in weight but formed in the same fashion as concrete.

http://www.taunton.com/finegardening/pages/g00117.asp

Hope this helps.

The hypretufa may be OK where the writer of the magazine article lives, but I doubt it would last a winter in a freezing climate. The materials in the "concrete" mix do not lend themselves to durable concrete.

If you do use it, make sure you do not over-mix the mess. The perlite and moss will fall apart quickly.

Dick

Thanks for the info about hypertufa - in addition to the current project of a cement slab to cover the septic tank - we are going to be making a pond and of course the artificial rock would be perfect around our pond - does anyone have a reliable site to buy this hypertufa stuff?