GAUTENG DEPARTMENT OF INFRUSTRUCTURE DEVELOPMENT BUILDING ASSESSMENT REPORT WET SERVICES 78 FOX STREET BUILDING

Transcription

1 Report for Department of Infrastructure Development Wet Services Preliminary Report: 78 Fox Street Building October 2014 GAUTENG DEPARTMENT OF INFRUSTRUCTURE DEVELOPMENT BUILDING ASSESSMENT REPORT WET SERVICES FOR 78 FOX STREET BUILDING OCTOBER 2014

2 Report for Department of Infrastructure Development Wet Services Preliminary Report: 78 Fox Street Building October 2014 Table of Contents 1. INTRODUCTION Design Criteria and Specifications Scope of the Services Scheme Report PROJECT SUMMARY Plumbing and Drainage Systems Water storage tanks Water reticulation Drainage reticulation Solutions Water storage tank Cold water reticulation Hot water reticulation Drainage reticulation Green star building Rain water harvesting Grey water harvesting Other green initiatives already required by SANS Part XA Water saving sanitary fittings Water meters Alternative energy... 8

3 1. INTRODUCTION 78 Fox Street building is located in the Central Business District of Johannesburg on the corner of Fox Street and Sauer Street, Gauteng (see Locality Map): Figure 1 - Locality Map The project brief, as issued by Gauteng Funding Agency (GFA), was to conduct an initial assessment of the building s plumbing and drainage infrastructure and systems and to provide recommendations regarding the repairs and renovations of the building. 1.1 Design Criteria and Specifications This project will be implemented in compliance with all the requirements of the National Building Regulations and SANS10400, with specific focus on Part P (Drainage) and Part XA (Energy efficiency for building) of the regulations. 1.2 Scope of the Services Scheme Report This report deals with the wet services to be implemented based on the existing systems and proposed architectural changes to the building. 1

4 2. PROJECT SUMMARY 2.1 Project Description The building comprises of 34 floors, and is organised into three hanging volumes of nine office floors each. The respective floors above with 5.40 m high cantilevers house the air-conditioning plants, a cooling plant as well as the transformer station. The gross building area of the building is sqm. [incl. the basement levels] The current assessment of the existing building entailed inspecting the present state of sanitary, plumbing and drainages services within the building. Furthermore, the building does not comply with two elements of the National Building Regulations, SANS 10400; which relate to universal accessibility and the latest energy efficiency regulations. 3. Plumbing and Drainage Systems 3.1 Water storage tanks 78 Fox has a sectional steel tank located in a plant room on basement level 2 (Fig. 1). The water tank seems to be filling constantly due to excessive draw-off. All valves and pipe work is still intact, however some of the fittings show signs of corrosion. There is a 230m 3 pressurised water tank as well (Fig. 2), however, it is stagnant and not connected to any working infrastructure. The vessel was last inspected in January Another large sectional steel tank is located in the tower on roof level (Fig. 3). It is not clear whether the water is used by the mechanical equipment of for domestic purposes. All valves and pipe work is still intact, however some of the fittings show signs of corrosion. There are two sectional steel water tanks located on each of the mechanical floors. It is not clear whether the water is used by the mechanical equipment of for domestic purposes. Fig. 1 Sectional steel tank in plant room Fig. 2 Large water tank in plant room Fig. 3 Sectional steel tank in tower Fig. 4 Sectional steel tank on mechanical floors 2

5 3.2 Water reticulation Cold water transferred to the upper level water tank via a six booster pumps (Fig. 5) located in the plant room on basement level 2. The booster pumps are connected as 3 booster sets. Each set pumps water to a different mechanical plant level within the building above. Fig. 5 Booster pumps in plant room Fig. 6 Booster pumps in plant room Internal water reticulation to each floor is done via common ducts in the around the lift core. The sanitary ware on the upper floors and basements have been vandalised. The fittings can be serviced/repaired in some cases. Some fittings need to be replaced with a greener alternative in terms of water consumption. The lower ground floor sanitary ware is in a good working condition. Fig. 7 Urinals - lower ground floor Fig. 8 Paraplegic bathroom Fig. 9 Toilet cubicle Fig. 10 Kitchen sink 3

6 Fig. 13 Shower in basement ablutions Hot water is pumped to the building from 2 x boilers in the basement. There are some geysers located in the ceiling voids as well. Fig. 12 Boiler in basement plant room 3.3 Fig. 13 Geyser in ceiling void Drainage reticulation The main drain pipes all mainly ran down in two separate locations. The drains connect in the basement, then connects to the municipal sewer. There is a sump located in the basement to pump waste water up to the sewer connection. The drainage reticulation is at the end of its lifespan. There are many leaks, mainly caused by pin holes in the pipe work. The pipe are rusted from the inside out and must be replaced. Fig. 14 Rusted drain pipe Fig. 15 Leaking drain pipe 4

7 Fig. 16 Suspended drain pipe Fig. 17 Damaged rodding eye Fig. Sump in basement plant room 5

8 4 Solutions The remedial work required to meet the minimum national standard and reinstate the plumbing and drainage systems is recommended and a high level budgetary cost for the remedial work is presented. 4.1 Water storage tank The existing water tanks should be drained and inspected for any damage or rust internally, then disinfected if deemed to be in good condition. Apply the following disinfection procedure to any storage tank: a. Remove all visible dirt and debris from the inside of the storage tank; b. Fill the storage tank with clean water and then drained until empty; c. Refill the storage tank with clean water and add a solution of sodium hypochlorite to the water until a free residual chlorine level of 50 mg/l in the water is measured; d. Leave the chlorinated water in the tank for not less than 1 h and not more than 3 h, after which (in turn) open each terminal fitting served by the storage tank, starting at the one closest to the tank and working progressively away from the tank, until the water discharged begins to smell of chlorine, then close each terminal again; e. Do not allow the storage tank to become empty during the discharging described in (d); refill and re-chlorinate the tank as in (c), as necessary; f. When the discharging is carried out on the terminal fitting furthest from the tank and the smell of chlorine becomes evident, measure the level of free residual chlorine in the water discharged. If the concentration of free residual chlorine is less than 30 mg/l, repeat the disinfecting process, starting from (c); and g. Keep the tank and pipes charged with the chlorinated water for at least 16 h and then thoroughly h. Flush them with clean water until the free residual chlorine level at any terminal fitting does not exceed that present in the clean water from the mains. In the case of pipework under pressure, apply the following procedure: a. Carry out chlorination treatment through a properly installed injection point, using a chemical pump at the start of the installation until the measured free residual chlorine at the end of the installation is at least 20 mg/l; and b. Leave the chlorinated water in the system for at least 24 h, after which flush the installation with clean water until the free residual chlorine level in the water, measured at the furthest point from the injection point, does not exceed that present in the clean water of the mains. NOTE 1: Disinfection should be compatible with the pipe system manufacturer s specifications. NOTE 2: Should the use of alternative disinfection systems be considered, the process should be performed under the supervision of and the results certified by a suitably qualified specialist personnel as specified by the manufacturer of the materials and equipment. NOTE 3: Following the performance of the disinfection process, it is recommended that a water sample be obtained and submitted for quality analysis in terms of the requirements given in SANS and SANS Alternatively, cold water storage tanks should be replaced to ensure a continuous water supply to the building in event of a municipal main failure. 4.2 Cold water reticulation The cold water reticulation system and pipe work is still in working condition. The system could be thoroughly inspected and tested for signs of severe rust. Some of the galvanized pipes have rusted through over the past years, these sections must then be repaired. 6

9 We recommend that all galvanized pipes be replaced with new galvanized pipe or polypropylene random copolymer (PPR) / multilayer pipe (MLP) to be used in terms of green star and ensuring the future longevity of the installation. All cold water reticulation should be replaced to ensure longevity of the system. All the installation must be in compliance with SANS part Hot water reticulation We recommend that all hot water pipes be replaced with a polypropylene random copolymer (PPR) or multilayer pipe (MLP) to be used in terms of green star and ensuring the future longevity of the installation. The hot water reticulation system and pipe work is still in working condition. The system could be thoroughly inspected and checked for signs of severe rust. Damaged/rusted sections can be repaired and reinsulated. All the installation must be in compliance with SANS part 1 To comply with the part XA building regulations, 50% of the hot water generation energy must consist of alternative energy i.e solar panels or heat pumps. The hot water vessel is past its life expectancy and should be replaced. 4.4 Drainage reticulation The existing cast iron is in working condition, however due to the age of the installation the cast iron pipe work would be corroded internally. Green star rating will be improved when adherence is given to the PVC mineralization category with in the green star requirements. We recommend using HDPE pipe as a replacement. Installation to be in accordance with SANS part 2 and the national building regulations part P 7

10 5 Green star building In attempts to get a 5 green star rating on the building, we suggest the following: 5.1 Rain water harvesting Rainwater is collected by capturing rain via the roof and then storing it for purposes of WC flushing, irrigation or fire prevention. Water is captured on the roof though gutters or specialized rain water capturing systems. The water is then stored in a water storage vessel. From there the water will be filtered by a rain water treatment plant and stored in a separate storage vessel. The storage vessel will be large enough to supply the intended demand for 5 days. The water is then pumped back into the building for the purpose of intent. The water produced by the water treatment plant in not safe for human consumption, thus should be kept separate from the domestic water supply. 5.2 Grey water harvesting Grey water is another good way to conserve water. However, grey water is only recommended for irrigation purposes. Similar to rain water it is stored in a storage vessel, then treated and again stored in a separate vessel from where it will be pumped. Even though the water is treated by a treatment plant, there are many pathogens that remain in the water. These pathogens may cause many health issues within the building it is used when consumed by the occupants. 5.3 Other green initiatives already required by SANS Part XA Water saving sanitary fittings The building regulations require that sanitary fittings within the building be of the low flow type: WC to have 3 and 6 liter dual flush options Wash hand basins to have a maximum flow rate of 6 liters per minute Showers to have a maximum flow rate of 9 liters per minute Urinals to flush 0.8 liter per flush Water meters Water meters must be installed on each section of the building to detect higher usage levels. With this information the efficiency of the water reticulation system can be measured and faults can easily be detected Alternative energy 50% of the energy used through the conventional resistive heating of water shall be of an alternative source: Solar Air to water heat pumps Gas Coal 8