chimney cap alternative?-2

[Aaron]

I have just finished putting lickem' & stickem' stone on my chimney and I am ready to pour a cap on top. The "chimney" is totally non functional and is just for looks. It measures 4'x8' and is aprox 18'-20' tall, and is basically a "stick framed" structure (2"x4" 16"oc walls and 2"x6" 12"oc ceiling).

Is there a "lighter" alternative to pouring a 4" thick cement pad on top for a cap? A 4"x4'x8' would weigh about 1200 to 1600lbs. correct?
I did price having a custom fit cap made out of tin, but it was about 5 times that of a concrete cap.

I am currently laying tile in a walk in shower, and the floor tile is lade over a Poly styrene pan (Schluter-Kerdi system), is there a similar product for concrete?--a foam base or foam core type system?

I attached a pic, I can add close ups if needed.

[tscarborough]

You have a non-functional chimney chase covered by fake rock and you want a fake cap to top it off? My recommendation would be to cap it with foam and use a one coat cementious base coat with an elastomeric finish coat in light gray.

Unless it was detailed and flashed correctly, however, all you have built is a conduit for water intrusion into your home.