Lyons O'Neill

Pembridge Square

The existing property is a combination of the main 3 storey residential building with a small basement level, together with a single storey extension between the edge of this building and the neighbouring property. The existing vertical structure to the building comprises of a number of both exterior and interior flank walls, both formed with solid masonry. The upper level floors are formed from timber joists spanning between external/internal walls whereas the ground and basement floor construction is ground bearing concrete slabs. The proposed development will comprise of a new basement level under the full footprint of the house and a new rear 2 storey extension, together with internal structural alterations.

The existing brick perimeter walls will be underpinned in mass concrete following a hit and miss sequence. Reinforced concrete L shaped retaining walls will be cast inboard the mass concrete underpinning. The new basement slab will be formed using a suspended concrete slab, tied back into new retaining walls, whereas the new ground floor slab will be formed using concrete cast onto a metal deck, spanning between steelwork placed within the depth of the floor. The new steelwork will typically span between new steel columns forming goalpost frames and loadbearing masonry walls. A new 2 storey steel portal frame spanning from basement level to 1st floor level will provide the stability to the building in the new arrangement.

Architect Archio
Contractor Room Below
Contractor Room Below