Part 2 : Coating materials for Aluminium cladding – Misery of “Self-cleaning”

Following with our part 1 discussion, we now share another hot topic about coating applied on the aluminium. “Self-cleaning” is indeed a merchants’ name . The behind sciences are varying from among different manufacturer. We have conducted some comparison among different materials being applied to the cladding surface.

Theory of “Self-cleaning”

Self-cleaning : Hydrophilic approach 

In short, there are a few theories behind the “self-cleaning” . One typical approach is to create the surface which reduce the water surface tension. When the water droplet lands on the surface, the water droplet has formed an wetting angle to the surface of cladding. The stronger the water tension, the more acute the wetting angle is. The below diagram explains the wetting angle and how it carries the dirt / stain / attachment on the surface. Different manufacturer has formulated different chemical materials to reduce the water tension and flatten the wetting angle. The water is to carry and flush away the dirt. The most typical chemical approach is to create the coating surface which offer better hydrophilic (hydrophilic is origin from latin word, the word philic means love).

 

 

Self-cleaning : Photo-catalytic Oxidation 

Another theory is by “Photo-catalytic Oxidation” . We are not Chemist and cannot cite the theory . Nevertheless, we found one extract from “Chemosphere 193( 2018-198-206)” ,  there explains the “photo-catalytic oxidation” with the below graphic. In short, it is the oxidation process to the VOCs by UV and Photon. This is again alleged by many peers as ” self – cleaning” , but obviously the theory is very different from “hydrophilic approach”

Self-cleaning : Hydrophilic approach

To the contrary of “Hydrophilic” , some manufacturer applied the opposite ; hydrophobic approach. The theory behind is to keep the strong water tension of the droplet and let the droplet to “PICK” the dirt away. From our very preliminary scanning , this technique was more relying on the water – repellent nature ,

Product in the market : – 

We have encountered different approaches in the market. All suggest their “self-cleaning” properties. We try to cite some examples to illustrate different theory behind . We are not in the position to comment each performance and indeed it is difficult to do comparison. We hope this articles can offer some ideas for future research

Kansai Paint : 

One of the product is made by Kasiai, we were given the understanding that the materials is silicon-based modified resin materials with their own additive untold to the public. This is to create the “Hydrophilic” by flush and deliver the dirt.

 

 

Hydrotech from TOTO

Hydrotect is the tradename by TOTO. We extract their self-allegation from their official website. In short, they claimed their coating technique is photocatalytic which is to OXIDE the VOCs in the air. Their website further suggests this “Hydrotect” can offer the hydrophilic surface to flush the dirt

XX Sheet film paper 

A manufacturer , named to be untold here, claimed that there film sheeting offer the self-cleaning. We cannot identify their theory online. Nevertheless, we did a quick water spray test on the surface. We noticed that the water droplet kept intact on the surface and did not appear wetting pattern which is for flushing the surface.  From the picture below, the water – droplet keeps visually keeps the sharp and the droplet drip pattern is in the form of line.

 

 

Fire Safety in Commercial Premises

Fire safety can be regarded as one of the primary considerations in building designs. The terms of fire safety cover a wide range of building concepts, ordinances, and regulations under the law. When we consider the fire safety works in banks, the concept of Fire Safety (Commercial Premises) Ordinance should not be omitted. The introduction of FS(CP)O is one of the ordinances which aims to provide better protection to the occupants and visitors on certain kinds of commercial premises.

Prescribed commercial premises and specified commercial buildings are under the scope of the ordinance.  For the captioned the premise, they are required to update that fire safety construction including means of escape, means of access, fire-resisting construction under the Code of Practice for the Provision of Means of Escape in Case of Fire 1996, Code of Practice for Fire Resisting Construction 1996, Code of Practice for the Provision of Means of Access for Firefighting and Rescue 1995 respectively. Also, the premises required to update fire services installation following Codes of Practice for Minimum Fire Service Installations and Equipment and Inspection, Testing, and Maintenance of Installations and Equipment 1994 when the total floor area exceeds 230 square meters.

As a building professional to cope with the above issue, a desktop study needs to be conducted first. It is essential to calculate the number/width of the exit door and exit route following the purposed usage of the premises. The comparison of the recorded plan and Fire Safety (Commercial Premises) Ordinance may draw attention to the fire safety deficiencies. The site visit is followed to identify the deficiencies. fire services system always associates with water supplies and electricity. For the aged building, some non-emergency services like electricity will be located in the exit route. However, those non-emergency services did not enclose by FRR materials. It may post a potential fire hazard. Insufficient width of the MOE route, insufficient number of exit routes to the required staircase, presence of the fire shutter in the exit route, absence of exit sign, absence of the exit door, etc are the common scenario for the aged commercial premises to deal with the ordinance. The reasons for the above deficiency can be caused by certain reasons including the change in use, the absence of the fire safety ordinance during the construction period, and unauthorized building works by the owners.

Boundaryless collaboration to turn state-of-art Architecture design into “down-to-earth” reality solution

In a highly congested urban context, how can a building stand out from the backdrop and become memorable ? There are strategies such as a practical internal layout, modern interior design and impressive building facade. Since buildings are usually arrayed in highly dense urban areas, the building facade becomes the first impression and first touch in many metropolitan cities. To create a distinct impression in international city likes Hong Kong, the architectural design created by powerful multi-cultural collaboration is the bespoke element underpinning the design solution.  

It is to the benefit of future users, landlords and every stake-holder of the development when the building is positioned and presented in the right site, right angle, right context and right location. To gear the architectural design toward practicality rich solutions, a down-to-earth technical analysis becomes profoundly important. K.P.D.O + GBE like many leading edge internationally award-accredited architects, believes a good balance of design, usage, layout, cost, and site features are essential to the development.

Grateful and thankful to collaborate, rather than presenting a simple yield diagram, K.P.D.O.+GBE. presented an aspirational solution showing the full site potential. K.P.D.O+GBE has analysed the details, negated technical deal breakers and prepared a sensible and approvable layout for the future user’s consideration. The turn-around for these are 6 days only. This assignment showcases and highlights our strong ability to find additional value whilst producing distinctive and memorable architecture.

 

Structural Appraisal to the Loading Case in Yuen Long Premise

When I was an undergraduate in Building Surveying, I learned from many textbooks that the structural design process usually starting with the loading assumption. This assumption is presented by outlining different loading cases. In simplicity terms, some loading cases are what we called UDL while some are point load.

Example of UDL

Example of point Load 

When we deepen the idea of loading further, there are generally three types of load including dead loads, live loads, and wind loads. Dead loads are due to the self-weight of the structure. Live loads consist of all the loads which are designated to be placed on the structure, For example, loads of people and furniture. This live load is strongly correlated to the usage and obviously the heavy-load machine will demand strong live load capacity.  Wind loads generally come from the pressure of wind acting on the structure.

Example of live load, dead load and wind load

In order to ensure safety and health for the built environment, Buildings Authority has enforced the Building (Construction) Regulations under HK CAP 123. There emphasizes the minimum imposed load or live load in our term for different usage. For instance, the distributed load for the domestic floor is designed as 2 kPa while the general restaurants are designed as 4 kPa. The structural design should follow this stipulated requirement to attain compliance.

 

Drifting down the river, the user of the structure, i.e. the occupier in the premises, may mis-sue or alternate the usage without carefully considering the designated live load. In our many Structural assessments.We noticed the occupier might have over-loaded the structure unintentionally or might have alternated the usage which exceeds the permissible live load.

 

In the situation like aforesaid said, the structural element itself may exhibit some undue behavior like the development of a huge crack on beam component or deformation. Adversely speaking, it is a very unfavorable observation because the structural damage may cause immutable damage to the elements. Sometimes, immediate propping or secondary support may be required to stop the damaging.

The Case for Building Better Residential

Residential properties in mega metropolitan cities are often short of satisfaction for occupiers. Many may find their flat small, inefficient, and developers trying to cram in all kinds of features with the hope of justifying its price. This is a result of residential units built to prioritize developer’s profit over end user’s satisfaction. With WFH becoming a well adopted trend due to Covid-19, tenants and occupiers are now reexamining their homes, and demanding higher quality space that is compatible with the current environment, and less so on the building’s location or proximity to the CBD.

Taking the Kennedy Terrace project as an example, a building that was designed with the end user is the priority. With a peerless 3700 sqft for its 3 en-suite standard simplex, it sits comfortably on the top of luxury residential tenants’ shortlist. As a direct consequence of not building 1800 sqft flats, competing with the surrendering offerings, Kennedy Terrace achieved approximately double that of neighboring apartment buildings when compared on a per sqft basis. The ample ceiling height, efficient layout of the unit, and the centralization of the apartment’s electrical system make the flat the ultimate blank canvas for its occupiers to personalize the unit to their heart’s content

Increasingly, landlords and developers of luxury residential sites are now faced with a dichotomy, whether to prioritize the volume of units available, or catering to the undeserved demand for larger space such as Kennedy Terrace. While the decision to provide truly spacious flats at the expense of a number of units may seem counterproductive at the beginning, filling the glaring disconnect between developer and end user’s may be as rewarding, if not more. 

Conceptual Design for Shanghai Exhibition from Our Partner KPDO

Glad that we can submit the design & management proposal for the exhibition in Shanghai. The artistic design from KPDO has expressed the theme of 4 seasons, idea of regeneration, reborn and recycle.

Adopting the vertical blind creates both visual effect from different perspective, it also provides the good sound barrier for privacy.