Tilehurst

Mountnessing is a house built in 1884 by George Sherrin for Sir Sebastian Petre, with minor alterations made in 1906. The building is constructed of red brick in English bond, featuring limestone dressings, some exposed false framing, and tile-hanging, topped with machine-made red clay tiles. It has a complex plan and faces approximately west, with two internal and three external stacks. The house is two storeys high, with attics and cellars.

All windows are casements, many with rectangular leading. The ground floor windows, and some on the first floor, have chamfered stone surrounds and moulded stone mullions, with some also featuring moulded transoms. Three first-floor windows are oriels supported on profiled brackets, with exposed false framing in the gables; two of these have brick nogging below the windows arranged in an oblique square pattern. There are two gabled dormers with exposed false framing, which displays various regional styles, including close studding, square panels, and decorative patterns. The entrance features double half-glazed doors in a moulded stone surround.

At the southern end of the house is a square tower with a belvedere on the second storey, false framing below the windows on three sides, and topped with an ogival cupola and weathervane. The left return has a two-storey splayed bay and a moulded stone parapet gable. The eastern garden elevation features a similar two-storey bay with a close-studded gable, two stone mullioned and transomed windows on each floor, and a close-studded gable dormer. Near the southern end, there is a timber gallery on the first floor and twin gables with exposed false framing in a decorative style.

Inside, the original main stair and doors on the ground floor remain, while the upper floors have been altered. The house was originally named Tylhus.