Interior Logic is an interior design technology provider that also offers supply chain and installation management services to homebuilders. : (Bloomberg)—Blackstone Group Inc. is buying Interior Logic Group Inc. for about $1.6 billion including debt, preempting the company’s initial public offering and bolstering a bet on single-family housing. Private equity funds managed by Blackstone are acquiring the interior-design technology provider from a group including Littlejohn & Co. and Platinum Equity, according to an emailed statement Monday. Last month, Interior Logic applied to list on the Nasdaq under the ticker “ILG.” Interior Logic also provides supply-chain and installation-management services to homebuilders.