Block above a mean house (8)
I believe the answer is:
bungalow
'house' is the definition.
(bungalow is a kind of house)
'block above a mean' is the wordplay.
'block' becomes 'bung' (bung is a kind of block).
'above' says to put letters next to each other.
'mean' becomes 'low' (I've seen this before).
'bung'+'a'+'low'='BUNGALOW'
(Other definitions for bungalow that I've seen before include "Single-storey home" , "One-storey building" , "One-storeyed house" , "A one-storey dwelling house" , "Single storey dwelling" .)