The deal is part of Chubb's stated ambition to expand in the Australasia region where the market for electronic alarms and closed-circuit television is growing faster than in Europe.
"The acquisition is of major strategic value for Chubb in relation to the development of the business in Australia, Asia/Pacific and world-wide," Sir Ernest said.
Chubb, which has almost pounds 90m in the bank, will fund the deal from a combination of cash resources and bank facilities. The acquisition is the latest in a series of deals involving Chubb in the Australasian region, which accounts for more than a quarter of group sales, and its second in a year with James Hardie.
In December Chubb paid pounds 5.3m for Hardie's security monitoring and manpower division. Six months later it bought MSS Security, an Australian electronic security company, for pounds 19m cash.