Walk through the near empty Sarjeant Gallery and then tour its temporary home on Taupo Quay and you'll experience one of those "Now I get it" moments. Chunks of masonry on the inside of the building have fallen from the ceiling, not as the result of earthquakes but simply because the Queens Park building is deteriorating.
Senior curator Greg Anderson said that over time water has got into the internal walls. Then after skylights were replaced, the building started to dry out. That combination has seen masonry falling inside the gallery.
"It is falling to bits."
In one of those little ironies, some falling plaster hit the bust of gallery benefactor, the late Henry Sarjeant. Call it an omen. But it was the issue with building deterioration that prompted the Wanganui District Council to shut the building and move its contents to a temporary location on Taupo Quay.
Holes have been drilled through interior walls to find out what was behind them. What engineers found was unreinforced double brick walls and some of them are in need of urgent repair.
Even discounting any extension, the existing building will be earthquake-strengthened using a method called base isolation. It was the same system used in the new wing built at Whanganui Hospital where the building sits on giant rubber bushes that absorb the quake shake. About 90 of them will be put under the Sarjeant.
But using that system means what has been the Heath Robinson storage area for many years will disappear. The gallery extensions include the new purpose-built, climate-controlled storage area.
Mr Anderson said like any old building, the Sarjeant has its share of hairline cracks and these are monitored regularly to see what changes have occurred.
"We're genuine when we say we're trying to restore and enhance Henry Sarjeant's legacy. It's a magnificent building and we owe it to the community, and indeed the country, to bring it back to what it was and make it last for beyond the next 100 years," he said.
Jennifer Taylor-Moore, the gallery's curator of collections, said the renewal will bring it back to its original form, except the detail will be much crisper.
Everything in the gallery will be replicated. The wooden flooring will be removed and every single plank numbered so it can be put back in its original position once the foundations are upgraded. It's all in line with dictates from Heritage NZ. Some of the double brick walls will come out and be replaced by steel-reinforced concrete.
Apart from packaging - called travel frames - that are still inside the building, the Sarjeant is virtually empty. All the art works have been moved to the Sarjeant on the Quay, its temporary home.
It meant moving paintings, glass, ceramics, and works in marble to the temporary home. It also meant carefully swaddling thousands of priceless arts works and lugging them down the hill to the Quay.
The Sarjeant is a majestic building and certainly unique in this country. But while it's grand, it's not so grand that it overpowers what its purpose was - to provide a permanent frame for the art works inside.
"It's no exaggeration that when it was built it was referred to as the Rolls-Royce of art galleries. It was the best that money could buy," Mr Anderson said.
The redesign intends to have a small viewing platform that will let visitors look down into the old basement area and see the new foundations.
The basement was where staff worked but it wasn't designed that way. It was excavated sometime in the 1960s to provide storage. It's a rabbit warren: cramped, a little bit musty and difficult to maintain at precise temperatures and humidity levels that art works require.
"It's not a matter of nipping downstairs and shifting some piece of art upstairs. If it was only that easy. We couldn't get a lot of works upstairs because we simply couldn't get them out of here," Mr Anderson said.
It's only with the shift out of the gallery that the transition team, busily cataloguing the collection, have been the only people to ever see the entire collection which numbers close to 8000 art works.
The storage at the Taupo Quay gallery is itself state of the art and will return to Queens Park when the redevelopment is complete.
Ms Taylor-Moore said having a climate-controlled storage environment on Queens Park will be a godsend for the collection.
"The climate in the old basement fluctuates dramatically so it was not a great environment for the painting. And we had no room. Paintings were just leaning up against the pillars and that cut down access for staff as well. The low ceiling and archways made moving stuff around hugely difficult."
Mr Anderson said the Sarjeant collection is roughly the same size as the Christchurch city collection.
"What it means is Wanganui has this vast chunk of the country's cultural heritage, about 400 years of art history. And that significance is what the Government's contribution [a promised $10 million to the redevelopment project] is predicated on," he said.
"We want to get this place fixed, come back and get back into business."