From before Roman times roof slates have been fashioned from the beds of limestone which underly the western part of the Estate. A high proportion of Estate houses and parts of Burghley House itself are roofed with Collyweston Slate. These roofs require regular attention, being stripped and relaid perhaps every 50 years or so.

These attractive roofs are to be found widely spread across this part of England, and the shortage of new material is now an issue of national importance. Since Burghley possesses most of the known deposits of workable slate log, it may be that in years to come the Estate can help to address local conservation and national heritage concerns over the progressive decline in the number of Collyweston slate roofed buildings.