Refurbishment of a Modern House, Wargrave, Berkshire

We were asked by the Architect to devise the new structure for extensions to a 1960’s house. The existing structure is an exposed steel frame and, for once, we also had the original Engineer’s drawings, along with a site photograph of the frame without cladding.

The house is a two storey steel framed rectangular box, similar in arrangement to a box kite, with hidden diagonal braces stiffening the upper storey. All of the columns are square tubular sections that pass continuously from roof down through the first floor to mass concrete pad foundations. Lateral stability of the building relies on these columns, and their structural continuity through the first floor. As expected this bracing system was found to have no additional capacity, and so our new extensions were structured using similar arrangements of tubular columns and rolled section beams, although in our case circular section tubes are used. The roof and floors are timber joists, as in the original, and foundations are shallow pads. As the site is subject to frequent flooding our calculations allowed for significant water pressure caused by flood water flowing under the building.

Architect John Pardey Architects