I went with a raised wooden deck. Allows for airflow underneath, and importantly is NOT a heat sink!
so theres NO heat plumes when viewing

in hot months
Also 2 mt. walls with fold downs to 1.5 mt. on N,E,W sides
North wall fold down is needed for Andromeda in Oct/Nov as she's low on the horizon 14deg

with 2 mt. height walls Max horizon I can get down to is 47deg.