Plumbing Africa July 2019 | Page 42

40 PROJECT “One thing that proves a common challenge in development like Katherine Towers is that when you are dealing with tenants, the tenant criteria can change all the time.” Says Trinesh Chanka of Izazi Consulting Engineers, “We chose copper for the installation because we went to tender on alternate piping solutions, and what we found is that the overall cost to the client at the end of the day is still more expensive for the alternate piping solutions. You will get a lot of stories from a lot of suppliers telling you that alternatives are cheaper, but then you start investigating as we did, and the result is that on a project such as Katherine Towers, the entire system is cheaper in copper, and this needs to be factored in for the client at the end of the day because everything is price sensitive these days.” Security on site is obviously important and should definitely be an element where no corners are cut. Two 5 000ℓ hot water storage vessels and heatpumps powering the hot water generation system are installed in the plant room on the ground floor. fail, there are electrical back-up elements in the storage tanks that would turn on automatically on a false signal from the heat pumps. The hot water is circulated throughout the building, up one of the ablution cores, and then turns on the topmost level and down the next ablution core, and then returns to the boiler. There is a ring of circulating hot water with no dead legs longer than 12m as per the requirements of the national standards. The domestic cold water installation consists mainly of large bore galvanised steel piping, typically from 50mm to 100mm. Small bore cold water piping as well as all hot water piping was plumbed using copper. A common noting or complaint from industry is that plumbers want to stay away from copper because of theft, but according to Leon Tobias of Jazzman Plumbing, “in all reality copper is still a cheaper option – even considering the theft element. The cost difference in fittings is vast between copper and plastic piping systems, even though the pipe is more or less the same price. When you look at big installations like this, copper lands up being highly competitive. Other companies may argue that plastic piping is better and faster to install, but for the plumbers on site chasing of the walls is still needed, you still have to install the pipe, still have to crimp the fittings and so on, so the time spent is not actually less.” July 2019 Volume 25 I Number 5 All of the waste lines installed are the Valsir HDPE system and the rainwater system installed is the Valsir Rainplus system. Rainplus was selected because it was also a cheaper overall solution and because the systems are interchangeable, it was just easier to run with. In terms of the HDPE drainage system, it was selected simply because it is a more robust system than PVC and its longevity is superior. You also don’t have the risk of the issue of glue coming undone in a couple of years. PRODUCT CHOICES Jazzman Plumbing contributed to the choices of sanitary and brassware, which specified the same products as the Sasol Head Office, which is two buildings down. The choice of products were based on an overall experience with the brands, that are reliable and available. One particular thing about choosing copper and galvanised pipework was that for a maintenance service, this is readily available from any plumber, and you also don’t need any specialised fittings or tools to weld the piping, which is one of the advantages of using a standard copper or galvanised system. Also, if a leak is sprung at midnight, the chances of you finding someone who deals with copper or galvanised is much more likely than with any specialised pipe system. IMPACT ON EFFICIENCY AND SUSTAINABILITY The Katherine Towers project is on par with the Green Star rating system for water usage guidelines. There are low-flow fittings installed on all units, so all of the basins, taps, and WCs are low flow. UNIQUE SYSTEM ELEMENTS One of the things that was initially a worry for the wet services team was the fact that building was 20 storeys high and the plant room was on the ground floor. If you have to estimate on a 20-storey building with each floor being 3.5m high, this equates to 70m tall, which then www.plumbingafrica.co.za