Holdfast Training Services Trial Blog

Introduction

Introduced previously is my current short-term project; designing a fitout for a Vetwest animal hospital. This is my first project as a Project Leader (PL), essentially project managing from start to finish. Before leave I/we submitted a concept design solution for review by our client, the managing contractor, Perth Citi Fitout (PCF) and their client, the building occupier, Vetwest. This blog discusses the on-going project and challenges.

Concept Solution Review

Reading my first client email correspondence, with reference to the concept design, I am already sensing the commercial challenges of the client facing side of design consultancy. PCF are concerned about changes we have made from their initial thoughts, particularly referring to the mechanical design of the air-conditioning (A/C) system. This is because we have included additional equipment which will increase their costs and eat into their profit margin. Without seeing the contract between Vetwest and PCF it’s hard to know if PCF are on a fixed price contract or not. I think they are as indicated by the technical data sheets they supplied us for the air conditioning units, which included a supplier quote of AUD $55k for 3 x Daikin split DX Variable Refrigerant Volume/Variable Refrigerant Flow (VRV/VRF) units.

Our concept design suggested 4 x packaged units costing circa AUD $70 – 100k. This was based on the layout split into four zones and included a dedicated unit for the HEPA filter in the surgery room. Packaged units aid in mitigating operational interruptions for maintenance as they will all be roof mounted. But PCF’s proposed split DX units would mean the indoor unit being located in the ceiling void which would disrupt operational use, including treatment/surgical operations. There are also other benefits of using packaged units but PCF, with confirmation from Vetwest, want to keep the costs down. That’s absolutely their prerogative but our view is split DX units are more suited to domestic buildings rather than commercial.

Although not our contractual duty, we feel we must look out for the interests of Vetwest and provide a design solution to their requirements, especially as they are seeking Australian Veterinary Association (AVA) hospital accreditation. This will indirectly aid PCF because if they fail to deliver the scope of works in accordance with Vetwest’s specification then they will become liable for variation charges.

How to manage this…

In order to tackle this I set about highlighting the benefits, via justification, of our design. Annoyingly, this information had already been submitted, written into a Consultants Advice Note (CAN). But, not wanting to simply reiterate this information, I set about giving the problem its due diligence by providing additional information which I gained from further research. This gave me the opportunity to review our design myself and pick-up on a couple of improvements that could be made. For example, the specific requirements of the Accreditation Scheme for the AVA (ASAVA) referring to the prohibition of any Air Transfer Grilles (ATG) and requiring a dedicated exhaust fan to outside the facility for the isolation room. This also included a dedicated exhaust fan and a motorised volume control damper connected up-stream of the supply air (SA) grille. This ensures the design’s ability to maintain negative pressure and if the exhaust fan should fail the SA damper can be completely closed to avoid positive pressure build-up.

Talking this through with the Project Director (PD) we came up with a compromise and amended the concept design, see figure 1. We reduced the number of A/C units to three, utilising the split DX units PCF proposed to keep costs down, by combining the surgery room with the rooms in the purple zone. The surgery room would therefore require its own SA leg of ductwork and a dedicated inline booster fan to overcome pressure losses from the HEPA filter unit. It would also still require a dedicated exhaust fan as air from the surgery room cannot be returned to the main A/C unit.

Other changes were: combining exhausting air from the cat and kennel rooms, via linked ducting, which reduced the number of exhaust fans by one; reducing rigid ducting and replacing with flexible ducting where possible, but still in accordance with BCA guidelines where maximum lengths of flexi duct must not exceed 6m; and; designing in two options for drainage, one using bucket and floor waste traps, the other a grease trap. This was TBC by Vetwest as to the outcome of their application to Water Corp for a trade waste permit. Ideally this should have been done before so we knew the exact requirements for which we are being asked to design to rather than us having to suggest multiple solutions.

I also drew-up three hydraulic concept designs for: hot and cold water, oxygen and suction, and drainage.

Figure 1. Revised Mech Concept Design.

Next steps

These changes were submitted to PCF and Vetwest for review and I am awaiting their feedback. Vetwest physically gain access to the building on the 1 Feb so is the earliest any on-site works can commence. Therefore, once the concept design has been approved and frozen (hopefully in the next two days) we have said we can complete final detailed design two weeks from then. So hopefully ready by the 1 Feb. In the mean time I am cracking on with software based heat load calculations so I can size the A/C units for the supplier to order in and stay inside lead times.

Heat load calculations

Figure 2 shows an example of my initial estimated heat load calculations – using the Australian Institute of Refrigeration, Air Conditioning and Heating (AIRAH) template.

Figure 2. Estimated Heat Load Calculations for the yellow Zone.

For detailed design NDY currently use a software package called TRACE to calculate heating and cooling loads in order to aid sizing of key plant, such as, A/C units, boilers, etc. It is shortly to be superseded by an advanced programme called CAMEL; I vaguely remember Ben Foster making a pun about it when comparing it to Hevacomp. CAMEL has the added bonus of integrating its building details and input data with another software package called BEAVER. BEAVER is a building energy simulation programme which is used by the majority of building owners/occupiers to estimate: heating, cooling, fan, equipment and lighting energy consumption. However, for this project I will be using TRACE.

What did I learn?

In summary, so far – a lot! It really is just like conducting one of the projects from Phase 1, so in that respect that was perfect training. The only real difference is the standards being Australian – but then they are very similar and searching for them is the same.

Stakeholder engagement is key. We had an initial project meeting before Christmas and followed it up with a site recce. Getting stuck into the detail this past week has highlighted a number of areas that needed clarification. Therefore a number of RFIs, directed at both Vetwest and PCF, were sent, all to aid project management. The good old fashioned telephone being the preferred method, with all communications followed up in writing, be it by email or CAN.