The site is significant to English Heritage (who rate is Grade II*) because, unusually, it is a purpose-built gallery for the collection of a single artist; still more so because GF Watts commissioned the building in 1904 shortly before his own death to house his own works. The original buildings were of mass concrete and brick walls with roughcast render externally, and lime render inside. The new architects made clear distinctions between preserving the best of the existing fabric and making major interventions to upgrade the galleries to modern environmental standards for the long term preservation of the collection; design interventions and restoration were carefully researched and faithfully implemented with no fakery or pastiche.

Winner of RIBA Regional Conservation Award