Teams of heritage experts and volunteer architects and engineers have gathered to devise repairs to some of Canterbury's most treasured landmark buildings, which were severely damaged in Saturday's earthquake.

One of them is the Gunyah Country Estate, at Darfield, 45km west of Christchurch.

The luxury lodge, built in 1912, had six brick chimneys collapse and fall into the centre of the roof.

Bricks crashed through the ceiling of the bedroom of owners Simonetta Ferrari and William Cottrell.

Their three children and six guests were unharmed.

"Our ceiling came down as I was trying to get out of bed," said Miss Ferrari, a prominent garden designer.

"I can't believe we got out.

"The quake was something: it was as if the house had been hit by a train 20 times, jolting back and forth and there was a bomb underneath.

"I have whiplash pain in my neck and back and William was struck in the back of the leg by a brick."

A tarpaulin patch in the roof blew off overnight and had to be replaced.

The beam holding up the first floor was cracked and the floor bowed, the dining room and antique furniture was smashed.

"The house took years of work to restore and now it will take months to repair."

A popular Canterbury attraction, the historic Deans Homestead at Homebush, was also damaged and about 7km away, the front of the Rhodes family's Hororata Homestead was destroyed.

The stone church at Hororata lost its spire and is severely cracked.

Selwyn District Mayor Kelvin Coe said about six homes had been condemned and 39 others suffered significant damage.

"I don't think they can be repaired. They tend to be older buildings but there are some relatively new ones," the mayor said.

"A lot of chimneys have come down and some have gone through the roof and people are quietly patching them with tarpaulins and corrugated iron."

Mr Coe said the council's building code included the possibility of earthquake because the Southern Alps fault line was not far away.

At Kaiapoi, in the Waimakariri District, the Blackwell's Department Store Building lost its facade.

"A lot of lovely buildings, including Bells Auctions, Kaiapoi Museum and the Gospel Church have been damaged," said a council spokeswoman.

At the port in Lyttelton, a town often described as a historical treasure trove, the Historic Places Trust's Lyttelton Timeball Station lost a chimney and the fire sprinklers were set off.

The 1876 station, which is the only surviving one in the country, is closed to the public until it can be repaired.

At Diamond Harbour, the 1880 Godley House had its chimneys topple and slide off with such force that they cleared the veranda below and thudded into the lawn.

At Governors Bay, Sir Miles Warren's historic home Ohinetahi was also extensively damaged.

The quake was also felt in South Canterbury. In Temuka, at the two-storey Royal Hotel built in 1894, a huge concrete architectural feature on its facade fell, smashing into a balcony on the way down and opening up a large hole.

"It's a real mess," said proprietor Maz Opele. "We've had the front of the building braced in the meantime."

The Temuka Hotel has a crack along its roof but is still open.

Historic Places Trust spokeswoman Shelley Fry said the trust did not know the extent of damage to Canterbury's heritage buildings.

But it would work with owners, councils and insurers on ways to retain heritage fabric in building repairs and for seismic strengthening.