Periscope
Doubts over new green panels on building walls
"The vertical green panels are just
to lower general temperature to a
certain extent, can they really make
changes to residents' behaviour?" she
asked. People nowadays care more
about convenience and comfort, and
they may not cut down on the usage
of air-conditioning, she said.
"The green panel installation is one of the many alternatives. They (the Housing Department) can test more (options)," Ms Ng said.
Jim Chi-yung, chair professor of geography at the University of Hong Kong, said evaluations to be made by the government were likely to focus only on the "horticultural aspect" rather than on the "scientific aspect".
"(If I were testing the project), I
would look at the temperature drop,
insulation effect and humidity level
(after installation)," Professor Jim
said. "I think they will merely look
at the plant growth and the
difficulties in taking care of the
plants."
He also questioned the maintenance of the panels. As the panels are to be fixed on vertical surfaces of a building, it is difficult to carry out irrigation.
"Is it practical? How will they carry out maintenance work in the future?" he asked.
The expert has been carrying out tests for suitable plant species on green panels at a 200-square-metre rooftop garden in his university.
The Housing Department spokeswoman said the future maintenance cost would be covered in the housing estate management fee, which was to be borne by tenants.
A scholar who researches on construction at the Hong Kong Polytechnic University and wishes to stay anonymous, meanwhile, expressed concern about the hygiene and health matters that could be involved. She said under the city's subtropical climate, the evergreen plants would easily attract insects and mosses. "That may cause deterioration (of the structure) of the green panels," she said. Water stains might also be resulted on those walls with the panels because of the wet climate.
Jim Chi-yung (left) and Kim Chan Kim-on (right) both
call for more planning on greening policies.