Building an apartment block

What changes above two floors

Once you go past two floors, the reinforced concrete frame is doing the work and the walls are just infill. That means the structural engineer leads the design, the foundation is sized on calculated loads rather than experience, and the concrete has to be tested rather than trusted.

The approval route lengthens too. Depending on size and location you may need a NEMA project report, a fire access review and a formal drainage design, and those take time that has to be in the programme from the start.

• ✓Engineered frame, tested concrete, certified steel
• ✓Water storage, pumps and a riser designed for the whole block
• ✓Waste and stormwater designed as one system
• ✓Parking and setbacks decided by the county before the design is fixed

Where the money goes

On a small block, roughly a third of the cost sits in the frame and slabs, and about a fifth in finishes. Lifts, generators and boreholes are the items that move a budget most, so decide on them early rather than adding them at the end.

Questions we get asked

How long does approval take for an apartment block?

Plan for three to six months from the day drawings are submitted, longer where a NEMA project report is required. Counties differ, and the queue matters as much as the paperwork.