XtremeBlock with Cellular PVC Insert

Designed to maximize moisture movement away from the envelope of the structure while offering a pleasing appearance
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The XtremeBlock is made from predominately recycled materials in our continuing efforts to be good stewards of the environment. It has been uniquely designed to maximize moisture movement away from the envelope of the structure while offering a pleasing appearance. Lightweight, easy to install, primed - ready to paint or prefinished to match the siding color.

Available with solid cellular PVC inserts in both 6x8 & 8x12 sizes and each of these can have a wide variety of predrilled holes. Also available in one piece polystyrene 6x8 with electric box opening or 8x12 with 4" round hole.

MB812 8" x 12" with insert - all options
MB68 6" x 8" with insert - all options
MP68EB 6" x 8" with electric box cut - no options
MP8124R 8" x 12" with 4" round hole - no options
1R 1" round hole centered
15R 1-1/2" round hole centered
4R 4" round hole centered
SM Split mount cut with 1" round hole
EB Single electric box cut centered
XX Specify color using our standard code

End Dams prevent water from running over sides, maintain horizontal spacing from siding

Pre Punched for easy screw mount

Over lapping bottom edge maintains shingle style best practice application

Large, easy to use mount header avoids weep over water penetration

Raised Diverter forces water to edge of block

Cellilar PVC 1/2” thick face plate provides secure screw holding

Available with or without pre-drilled holes
Primed ready to Paint or Prefinished in all Common Fiber Cement Colors.
All Hole Cuts are available in either MB812 or MB68 sizes.
Custom Hole Cuts can be ordered.


Split Mount Insert with 1” round hole. Split Insert allows quick install over a hose bib or a/c drain pipe. Shown in Cobblestone.


Full face with 1-1/2” round hole for a/c line or other lager pipes. Shown in Khaki Brown.

MB68 or MB812

Basic block – non drilled for on-site adaptation or used as flat mount. Primed white, ready to field paint.


One piece molded, non-insert, block formed for standard single electric box. Shown in Khaki Brown.