The escalating costs of building materials are jeopardising a first home buyer's $20,000 Kiwisaver grant.
The speed with which costs are rising is pressuring builders to invoke escalation clauses within so-called 'fixed price' contracts.
Lucy McPherson and her partner Ben Butterick signed up in July for a $545,000 dollar build yet to begin in Selwyn near Christchurch.
Already the price has risen by $7000.
If the cost breaches a cap of $550,000, she and partner Ben will lose their $20,000 Home Start grant.
She says the bank has warned them against going ahead, saying cost over-runs are in some cases hitting $60,000.
The 25-year-old who works in agricultural marketing says it is crazy and stressful for first home buyers - and they would never have ploughed their savings into Kiwisaver if they had known.