Pink Batts insulation is not the only building material that is running short as alert level 4 in Auckland cuts off both manufacture and distribution of all but essential building supplies.
It was revealed this week that Fletcher Building has stopped making Pink Batts under alert level 4, and even in Auckland has only "extremely limited" stock.
The CBS cooperative of almost 700 construction companies in Canterbury says several other product lines are also at critical levels across the industry: steel coil for roofing, RAB board, GIB wallboard, aluminium extrusion used in windows and doors, glass, and paint.
CBS executive member Mike Blackburn said the shortages are also stretching out waiting times to get products, so things like timber framing may not be delivered for months.
"Electrical appliances appear to be well stocked, however, almost everything in stock now is already booked by builders and new orders are generally requiring a lead time of 12 to 16 weeks," Blackburn said.
"Similarly with frame and truss, which means that orders placed today won't be delivered until December.
"But the reality is that this will probably roll over into the new year."
One electrician who is a shareholder in CBS, has been buying up cable, switchboards and fittings but is worried the business' work will dry up if builders can't finish projects due to other materials running short.
A house cannot be lined inside if the insulation has not been fitted.
If roofing runs short, unfinished houses will not be able to be closed-in against the weather.
The Building Industry Federation - which represents suppliers - is providing officials with lists of companies seeking exemptions to manufacture or operate their warehouses.
"By Friday week most lines of building products will have run out in L3 [alert level 3] parts of the country," said the federation's Julien Leys.
He expects limited exemptions might be granted next week.
So far, no exemptions have been given for any type of manufacturing at level 4.
As for travel exemptions to the construction sector - for instance, to deliver goods out of Auckland - many more have been rejected than granted so far.
In the four days to Thursday afternoon, 1053 construction sector applications were received and 68 were granted; 439 were declined; 301 needed extra information; and 245 were still being processed.
Mostly businesses were declined because they did not meet the threshold for essential work under the terms of the Health Order, the Ministry of Business, Innovation and Employment said.
To meet the order, work has to be either to address an immediate health and safety issue, or nationally important infrastructure as defined in the order.
"An alert level 4 business cannot produce non-essential products for delivery to alert level 3 regions, even if it is already manufacturing essential products," the ministry said.
Where products had both essential and non-essential uses, businesses should ensure manufacture was for essential purposes only.
"Having too many businesses operating during alert level 4 increases the odds of transmission with workers moving in and out of their home bubbles, connecting bubbles, and increasing the potential chain of infection."
The Government said the Construction Accord is working with it on the supply problem.
Accord transformation director Dean Kimpton said its forum of 60 industry leaders and MBIE officials has met weekly under level 4 and discussed the supply chain problems.