National's U-turn on housing density is one of many factors leading developers to put their projects on ice.
The party has pulled out of its bi-partisan agreement with Labour, confirming it will allow councils to opt out of legislation allowing three-storey homes on most residential land.
Subdivide Simplify Head of Strategy Troy Patchett says it will put developers off making decisions.
But he told Mike Hosking it's just one of many factors creating uncertainty.
"There's lending, there's immigration, there's the fact we've now ringfenced losses on development, building depreciation."
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