Manufacturer: Scottish Housing Group
Designers: W A Fairhurst/ Melville Dundas & Whitson Ltd
Period built: 1940s–early 1950s
Number built: 3400
Site of Prototypes: Dalrymple, Ayr.
Designated Defective in England & Wales – Legislation Repealed in Scotland.
Built as 2-storey semi-detached and terraced houses with medium pitch gable roofs covered with concrete tiles or occasionally, copper sheeting.
The external walls are usually rendered throughout.
The windows are set in a Precast Concrete window surround.
This system was also used to construct flats.
Substructure: Built on concrete pad foundations with a square rebate to receive the vertical column bases. Concrete strip footings.
Frame: Eaves height 6″ x 6″ Precast Reinforced Concrete columns with PRC beams at ground floor, first floor and eaves level which are connected to the columns via reinforcing loops protruding from the rebated end of beam and fixed to metal lugs which protrude from the column face and a concrete cover to joint.
External walls: Rendered 4 1/2″ brick with a 6″ cavity, 3″ breeze blocks tied together with metal ties.
Separating wall: 3″ breeze block cavity wall.
Partitions: 3″ breeze blocks.
Ground floor: Timber boarding on timber battens fixed to PRC beams by metal clips.
First floor: Timber boarding on timber battens is fixed to PRC beams by metal clips.
Roof: Timber rafters and concrete tiles.
The ground floor was sometimes be constructed with timber joists in combination with PRC beams supported by sleeper walls or intermediate PRC beams which are supported on brick piers.
Concrete ground floor.
Some external walls have been found to be devoid of wall ties.
Investigations have noted that the outer leaf of external walls are sometimes constructed from 3″ breeze-block or 3″ foamed slag blocks.
In some instances the frame was without infill concrete at column and beam joints.
In some instances central PRC columns were jointed about 2′ 6″ above the first floor level.
Cracking and spalling of the PRC columns and beams can occur.
Surface corrosion noted of the loops that project from the beam ends and also on the plates and pins that project from the columns.
Cracking and spalling has been noted around the door and window surrounds.
Carbonation and significant levels of cast-in chloride in PRC columns and beams has been recorded.
Burnside Crescent & Burnside Street, Rosyth.