They say things like 'it's a wooden frame with a brick facade, right?' or 'I'm sure the supporting structure isn't brick.' No it's brick. It's all brick. The walls on all sides in every room are about 30cm of solid brick with plaster directly on top. Even the internal ones.
If you want to run a new light cable or something you'll be using a hammer and chisel to make a channel to put it in.
http://dme.engin.umich.edu/stubbornstructures/
The only advantage is cost and speed of execution, they call them McMansions for a reason.
So if the panelised timber frame superstructure for an rectangular two storey house of 150m2 is approximately 14 metric tonnes, you're locking up 7 tonnes of carbon for the life of the building (minus of course the carbon emitted to plant, prune, fell, transport, mill, treat, get the wood to site, install it etc.).
If you can use more timber through the construction, all the more effect.
It takes pinus radiata about 25 years to reach maturity. Then it can be turned into buildings/ houses, and the carbon locked up in that structure, which can be e.g in the city or suburbs- somewhere there will never be suitable for forestry.
And then the forest can be replanted and the virtuous cycle begins again.
tldr; locking carbon up in timber gives more flexibility than just relying on standing forests.
Also houses made from brick have a lot more damage in an earthquake - the mortar cracks and the structural integrity is lost.
That said, it was mostly older brick premises, chimneys, and facades that caused deaths. "Falling masonry killed 40 people in Christchurch's February 2011 earthquake"
I'm not sure how it's done in the UK with brick buildings though. It seems like if you needed much insulation you'd end up with an inner wall and brick facade.
Some medium-rise blocks of flats use steel frame floor plates from concrete central pillars with external cladding approach but most new houses are brick.