"That on the application of the owners, The Martin Estates Company Limited, a new street on their property situate off Ardenlee Avenue, be named Shelbourne Road". (19th March 1912).
Shelbourne Road runs at right angles to several residential streets from Ardenlee Avenue to Onslow Parade. However, there are no properties which have this address and, consequently, it is not listed in some sources such as Royal Mail Postcode Finder.
Despite the slight difference in spelling, it seems likely that this street was named after one of the holders of the title "Earl of Shelburne", an extinct title in the Peerage of Ireland, or related titles. The title "Baroness Shelburne" was created in 1688 for Elizabeth Petty, wife of Sir William Petty, This argument is strengthened by the presence of Onslow Gardens / Parade / Park and Haddington Gardens in the same neighbourhood. Onslow (Shropshire, England) and Haddington (East Lothian, Scotland) are unrelated geographically but are also names of earldoms.
Shelburne is a barony in the south-western part of Co. Wexford, which includes the Hook Peninsula. Despite its resemblance to English names in -burn or -bourne, this is an anglicisation of Irish Síol Bhroin, originally the name of a population group which inhabited this area. The spelling with the addition of an O is also found in the name of the Shelbourne Hotel on St. Stephen's Green, Dublin. The history section of the hotel's website states that it was strategically named "after William, 2nd Earl of Shelburne, former British Prime Minister and former owner of the site." Our History - The Shelbourne Dublin McCready also attributes Shelbourne Road in South Dublin to the Earl of Shelburne (Dublin Street Names, Dated and Explained, p. 117).