The destruction predominantly affected the Lowlands, the Highlanders being a law unto themselves within their own social system, strategically using the mountains to defend their proud autonomy. Castles continued to be strengthened, often growing in size to accommodate larger buildings. The impressive 14th-century castles of Tantallon near North Berwick and Doune in Perthshire both contain a massive gatehouse employed to protect the entrance, and provide the lord with accommodation. This gave him full control of the castle's defences, necessary at a time when hired mercenaries were commonly used in private armies. For lesser nobles, the tower house was the perfect solution to the conflicting problems of comfort and defence. It became a popular high-security residence, being smaller and cheaper than a great castle. Tall and narrow with smooth walls and few windows, these buildings featured a raised entrance and crenellated parapet as the main elements of passive defence, relying on thick walls and great height for effect. Being of a simple yet flexible design, the majority were expanded and decorated in later centuries, and none exist in their original form.

The 15th century, fluctuating between periods of war and peace, allowed tower houses to retain their popularity among the lesser nobles, being secure, yet comfortable enough for everyday living. High Gothic principles became established in ecclesiastical buildings, and the construction of the great royal residences introduced the spirit of the Early Renaissance to Scotland. In the 1420s, James I began to rebuild Linlithgow Palace, which by 1500 had become a large and symmetrical structure, in contrast to the random organization of medieval castles. Designed as a quadrangle with an open central court, it was primarily a domestic royal residence with a system of corridors and stairwells and large, regularly placed windows. This hint of Renaissance order and elegance was markedly different from the usual defensive principles of high walls and small window openings. Once considered the finest in the realm, the central chambers would have been luxuriously decorated with painted plaster and wall hangings.

The Gothic style was still favoured in ecclesiastical architecture, most apparent in Melrose Abbey. Twice destroyed in the 14th century, the rebuilding left excellent examples of High Gothic, the east window being the work of the York school of masons, and the richly carved south transept by a French master mason, which accounts for the lavish use of decoration. The flying buttresses are of particular note, being structural, not merely decorative. Due to an increase in trade with other countries, wealthy landowners could afford to construct small churches, staffed by secular clergy to pray for the soul of the benefactor. Many small collegiate buildings were built at this time, predominantly with a Late Gothic flavour: the most unusual and extreme is the mid-fifteenth-century Rosslyn Chapel near Edinburgh, with its elaborate carving and decorative flying buttresses. Also around this time, the castellated features of castles and towers began to creep into church architecture, seen in the use of crow-stepped gables at St Michael's Church in Linlithgow, or the crenellated parapet at King?s College Chapel in Aberdeen.