It seems that the outdoor cages are being removed and new outdoor added on the end of the existing house, which seems to be being retained after extensive alterations (which is probably the best idea if the house can be converted as it will save money).
The building works shown here resulted in a new lemur enclosure added to the end of the house and an extension/ renovation of the indoor area. Visitors can now view the chimps indoors via the lemur area. The chimp outdoor enclosures remain these cages.