London-focused property investment group Workspace has signed a deal for the sale of a portfolio of non-core industrial estates for gross proceeds of £44.3m.The portfolio of 10 industrial sites, which was purchased by Capital Industrial One, was sold at a premium of 35% to the March 2014 valuation and reflects a net initial yield of 5.3%.Altogether the sites cover 281,500 square feet.Workspace Chief Executive Officer Jamie Hopkins said: "I am delighted to announce the strategic disposal of this portfolio of industrial estates at a substantial premium to their book values."There was substantial depth of demand for the properties from a number of potential purchasers and we are pleased with the result and timing of this sale."