The company, said the offering, together with £51.2m raised through a share placing in June, will help fund its regional development pipeline and replace short-term debt maturities.
The unsecured convertible bonds, due in 2018 will carry a coupon of 2.5 per cent.
The initial conversion price – the price at which the bond can be converted into stock – has been set at 509.73p per share, 35 per cent above the volume weighted average price of the shares from launch to pricing on 3 October.
Finance chief Joe Lister said: “This issue is another milestone in the group’s strategy in diversifying its sources of funding and will contribute to lowering the group’s cost of debt”.
JP Morgan and the Royal Bank of Scotland acted as joint bookrunners on the offering.