The old companies were themselves amalgamations of earlier smaller ones. Therefore, no company had a standard "house style". However, certain styles were associated with companies, such as the gothic styles on the INWR and the yellow-brick of the GNR.
West Cork and the WRC were made up of many, many small companies with but a few stations each, but the corrugated sheet sides, and low platform awnings werecommon in West Cork.
The GSWR had stone buildings, often with great ornamentation, while the DSER used a lot of red brick, but with their very distinctive round-roofed signal cabins accessed off footbridges.
The SLNCR started off with nice stone single-storey buildings but ran out of money, so later buildings were tin sheet.