26 PROJECT
From the ground up
By
Tanya Olckers with technical input from Vic Ball Plumbers and Marnus Pretorius , Wet Services Engineer
A new 88-bed private hospital in Malmesbury in the Cape was designed to be as efficient as possible while keeping budget as well as operating costs in mind .
Crest Care is a group of private hospitals aiming to bring superior healthcare to their patients . With the building of their new Malmesbury facility , water and plumbing were high on their list as it related to water supply and pumping systems through to drainage , types of soil and waste drainage materials and systems to be used as well as hot water generation and hot water return circulation .
The work included a below ground drainage and a conventional stormwater system . Twin City Properties acted as the developer while Crest Care was the client . The initial site handover occurred on 14 November 2022 , with the principal contractor ' s final completion slated for 16 July 2024 . The project scope included designing wet services covering plumbing , drainage , hot water generation , a deionised water treatment plant , domestic water storage and water booster pumps .
The above ground drainage was created with PVC while the water reticulation made use of CU Class ‘ 1 ’ pipe . All hot water and hot water return piping was insulated to prevent heat loss , and design was engineered to provide minimum lengths for hot water dead legs .
The hospital features medical suites , radiology , maternity , pediatrics , ICU , MRI , surgical facilities , pathology , and other services available on the website . Drainage systems utilised PVC-u piping , while domestic water supply used copper class 1 . The deionised water supply , for specialised medical equipment such as scope and bottle washers , used Geberit Mepla multi-layer piping , with the DI water treatment plant installed by UCS Services . The hot water plant comprised two 6 500-litre heat accumulators supplied by IEES , with GreenBro 50kW heat pumps , and energy-efficient Wilo Stratos Pico / 1-6 hot water return circulation pumps .
In a move that could be seen as counter-intuitive , the hot water loop did not follow the most direct path to the point of use . Instead , a ring feed was snaked through the building to minimise dead legs . This was also part of the overall spec provided for hot water delivery at point of use . This means that the waiting time for hot water at any draw-off point is less than eight seconds . The system maintains temperatures above 50 ° C at all draw-off points within the intended design waiting times .
All images supplied by WFP Consulting Engineers
Tank levels for treated and potable water were also included in the dashboard .
Tank system .
A plant area that included the hot water generation plant was created and consists of heat pumps with thermocubes and circulation pumps . A water storage tank with booster pumps and deionising water treatment plant were also included . The cold water was separated into two ring feeds to feed the ground and first floors .
The architectural design and layout of fixtures , ablutions and kitchens guided the drainage system ' s implementation . All waste fixtures were drained separately to the building ' s perimeter , where they discharged into purpose-built brick gullies . These gullies were designed to accommodate multiple waste pipes at different invert levels and angles while complying with discharge and overflow gully regulations . No underground connections were made inside the hospital ' s footprint , which increased the length of underground piping but reduced the risk of blockages . Special care was taken to ensure adequate venting and to enlarge waste discharge pipes where necessary and in accordance with SANS regulations .
Energy efficiency was prioritised in all pumping and heating systems , and design criteria were established based on occupancy
www . plumbingafrica . co . za @ plumbingonline @ plumbingonline @ PlumbingAfricaOnline January 2025 Volume 30 I Number 11