Quality, Consequences and the Construction Industrial Complex (# 31) All IMHO: NIOSH notes the main cause of Sick Bldg Syndrome is inadequate ventilation. To impact this we need to move to Dedicated Outside Air Systems (DOAS). VAV systems in reality deliver poor thermal comfort and inadequate levels of outside air even when they are designed and commissioned correctly, which is a very unusual occurrence. Dedicated outside air systems provide accurate, stable outside air with a more predictable energy profile. Also thermal comfort can be acuratly targeted with separate heating and cooling systems once they are decoupled from the outside air. In this scenario,…
I tend to write about what I see and experience as a way to help prevent my onset of madness. I also seek excellence over mediocrity and user experiences as advertised. I have been consulting on many 5 star hotel projects and they all have one thing in common, the standard of buildings services engineering (design and construction) is 2 star.
What this means in practice is that a very expensive hotel room experience can consist of:
- Noise from the AC unit (normally a very cheap FCU)
- Air blown directly onto the bed
- AC and lighting controls so complicated a training course is required
- Long waits for hot water
- Water fittings with too much flow and poor drainage.
Owners design brief, design management and procurement are the root of the problems. Getting it right from the start matters.
When reviewing a hotel design I use a bedroom and bathroom key criteria quadrant to assess the design.
- Heatpumps are very noisy (yes I am talking to you North America). If they are located in the room, their enclosures need to be treated acoustically.
- Outside air should be ducted directly or to within 100mm of the FCU/VRF/Heatpump units. Just pointing it vaguely through the room wall into the ceiling void is not acceptable.
- FCU chilled water and heating should be piped reverse return and include AAV’s, main plant room air separators and no local stainers at the FCU’s. This will greatly assists system reliability and performance in the face of what will inevitably be poor or zero maintenance.
- Possibly the most important factor is proper selection of diffusers to ensure that occupant comfort, low noise level and adequate ventilation mixing are provided. This can be assed via the ADPI (Air Diffusion Performance Index). My point here is don’t just throw on the drawing any old pretty diffuser, please assess and select it correctly.
- The DHWS should be a piped and pumped continuous loop, instantaneous hot water system with a maximum hot water draw time of 20 seconds at the furthest faucet.
- The pipework and particularly the waste pipe should be located and/or insulted to minimize sound transmission. The user should not be able to hear an adjacent room flush the lavatory!
- 10 ACH is the minimum for odour control and a shadow gap air extraction solution is effective and low noise level.
- Too much water is as bad as too little. Medium flow, not low flow fittings are required for luxury experiences.
- Oversized shower drainage is also required. Standing in a shower basin with high flow water from the shower head with slow drainage and pooling is not a luxury experience.
One final issue. Either I am losing brain function or room controls are way too complicated. The user should be able to control the room environment without a training course. I feel hotels are “show boating” when they install complicated room controls via a screen user interface. All users really want to do is turn the lights on, adjust the temperature and turn on the comedy channel?
It seems strange to me that more 5 star hotel room users do not complain. Personally I take action, I used to stay at the Media Rotana Hotel in Dubai and now I use another chain. This is because most rooms had fixed air diffusion blowing directly over the beds, hot shower water that took at least 3 minutes to run hot and you can hear the adjacent bathroom user flush the lavatory. Not 4 or 5 star! However the hotel lobby looks fantastic. You can tell, my life struggle is real! #firstworldproblems
If the hotel owner overrules the design team and insists on bad decisions that result in a professional engineer signing off a project he/she does not believe in. The engineer should IMHO, move firm or sector because unless users vote with their dollars and design professionals say no or abstain things will never change. Qualified engineers are, in my experience always in demand, so moving sector is absolutely a choice. We all get what we tolerate.
Related posts & links:
#41- Who Knew? – Commissioning Design Reviews Save Money, Time and Reputations ( https://www.linkedin.com/pulse/who-knew-commissioning-design-reviews-save-money-time-muggleton?trk=mp-author-card )
#68 – Hotel Design – How Many Stars? ( https://www.linkedin.com/pulse/hotel-design-how-many-stars-adam-muggleton?trk=mp-author-card )