Fletcher Building wants $750 million new equity from shareholders, has established $500 million in banking loans to strengthen its balance sheet and is in a trading halt.

The surprise announcement comes after the business announced recently it expected to lose nearly $1b on major construction contracts.

"The company is raising $750m through a fully underwritten accelerated pro rata entitlement offer, enabling eligible shareholders to purchase one share for every 4.46 they own...for $4.80 per share," it announced this morning.

That is a 23.4 per cent discount to the closing share price on NZX yesterday, the company said.

"The offer will comprise institutional and retail entitlement offers, with any entitlements that are not taken up by eligible shareholders and entitlements of ineligible shareholders being offered for sale in the institutional and retail book builds respectively," it said.

"In conjunction with the offer, Fletcher Building has also established a new standby banking facility of $500m with ANZ, MUFG Bank and Westpac," it said.

The offer and new bank lines would strengthen the balance sheet and enable the business to meet its longer-term strategic objectives, Fletcher said.