With climate change, all glass building facades have had their day
All-Glass Facades Won’t Exist in Sustainable Cities, Davis Baggs, Sourceable, 13 Oct 15 “……..Glass alone cannot cover all contingencies, and the hotter the summer sun, the less successful it is. In winter in cold and even temperate climates high transmissivity (untinted) highly insulated glass units with Low-E coatings are typical and work very well. Problem is, in summer unshaded glass lets a lot of heat in, and the very factors that work for the building and occupants now works against them letting heat in and keeping it in, very efficiently overheating buildings and people all the better for the air conditioning engineers (whose fees are often based on the size of the air conditioning plants) and suppliers (who designed some of the major software tools engineers commonly use to design buildings).
So to overcome this, heat absorbing and reflective glasses were developed and to greater or lesser extent are used in all glass facades in climates where there is any bite at all in the summer sun.
Herein lies some of the problem; heat isn’t just ‘heat’. Solar energy does enter buildings by conduction (efficiently offset by insulated glass units or IGUs) from the atmosphere but the majority enters via direct and diffuse solar radiation.
If we make the glass reflective enough to stop enough solar radiation to avoid overheating of unshaded all-glass facades, we create strong rogue reflections that cause accidents and literally melt cars. So we wind the reflectiveness back and bump up the tinting levels to absorb the radiation in the façade and this is where the next problems begin…………..
The human body is up to four times more sensitive to radiant heat than any other form of heat. In fact, we are more than two times more sensitive to radiant heat than all of the other heat loss or gain pathways (convection, conduction, respiration, and evaporation) combined. The body is highly sensitive to even small changes in radiant temperatures; that’s why we love radiators, heated floors and mass surfaces in buildings to retain heat and keep us both warm and cool.
But as you tint glass, it progressively absorbs more and more heat itself and it becomes in effect a large plate radiator. The darker the tint, the more heat it both absorbs and then eventually re-radiates even when it’s double-glazed, such as in IGUs. Its important to note that this doesn’t cause the room air to heat up much, so its not picked up by the room temperature sensors of the HVAC, but it does heat people up easily and effectively, even through clothes.
Even a few degrees of radiant temperature can make a room very uncomfortable. A radiant temperature increase (or decrease) of five degrees can make the room feel eight degrees hotter (or colder) without changing the temperature in the room…….
Let me share my experiences of a building I visited in mid-winter (January) in the desert, midway between Dubai and Abu Dhabi. It was comprised of two 12-storey office towers of azure blue (heat absorbing) reflective (silver blue mirror look to the outside) double glazed IGUs linked by a three-storey entry podium of clear IGUs……
At midday, things got even more interesting. The outside temperature had risen to 35 degrees, the inside air temperature was still 21 degrees, but the outside skin of the building in the sun measured 65 degrees and the inside skin temperatures of the blue IGU in the offices were 35.4 degrees. Interestingly, the clear insulated glass podium was an astounding 37.2 degrees – because it was not reflective like the blue IGUs, it absorbed more heat……the solar intensity in UAE at that time of year is similar to Australia in summer….
Unshaded all glass buildings as we know them now, have no place in sustainable cities of the future. https://sourceable.net/all-glass-facades-wont-exist-in-sustainable-cities/#
There needs to be a stronger framework for Aboriginal property rights
At the heart of current concerns are two apparent contradictions.
First, to get back their land, Indigenous claimants need to legally demonstrate continuity of rights and interests under traditional laws acknowledged and traditional customs observed and to demonstrate continuity of connection with lands and waters since colonisation. Similar requirements are stipulated in earlier land rights law to demonstrate primary spiritual responsibility for land and to have a right to forage, to economically use, land claimed.
Such special relationship with land that is usually of low commercial value, in turn requires land owners to live remote from mainstream work opportunities. The maintenance of tradition that is required to claim the land, and hold it, geographically disadvantages land holders in their engagements with 21stcentury global capitalism. This also raises important questions about what constitutes ‘economic development’ from the perspective of Indigenous land owners.
Second, in accord with tradition land is inalienable. There was no trade in land pre-colonially and so land was passed inter-generationally on the basis of descent.
I am not convinced that inalienability is a major hurdle to development………
What is more significant, in my opinion, is the issue of property rights and the legal finding that mineral ownership is vested with the crown alongside state assertion of exclusive rights to own and regulate valuable natural resources like fresh water, fisheries and even carbon for commercial purposes….
Unfortunately, the Native Title Act framework provides native title groups a far weaker property right, a mere right to negotiate with a window of opportunity of six months, at best, and a right of consultation, at worst. This has resulted in many benefit sharing agreements, although whether they are equitable remains a contentious point.
And as Indigenous people get back more and more of the continent, political pressure continues to deprive them of ownership of commercially valuable resources: minerals, fisheries and fresh water. And as resource hungry developers look to explore and exploit Indigenous lands, there is a risk that disparities between Indigenous and non-Indigenous Australians might increase rather than decline.
Equally unfortunately, while the dominant approach to Indigenous development focuses on ‘mainstreaming’ the only guarantees that Indigenous people have to resources are outside the market system. So, Indigenous groups may be guaranteed ‘customary’ non-market rights, but not commercial market rights.
The Australian Law Reform Commission has produced the only policy response to grasp this key issue when it recommends that native title rights and interests might be exercised for any purpose, including the commercial alongside hunting, fishing, gathering and trading rights and interests. This is a means to empower Indigenous land owners to have the freedom to make development choice, although such policy reform could exacerbate wealth and wellbeing differentials between those who own land and those who do not.
Others like the White Paper and the Australian Human Rights Commission focus too much on real or imagined over-regulation of Indigenous lands and seek the removal of what Mick Gooda and Tim Wilson refer to as ‘red and green tape that stifles Indigenous development’. This all sounds too much like Keating’s warnings about ‘workability’ and risks change that will be structural and disempowering of the Indigenous disadvantaged in favour of the rich and powerful.
It might be timely for those who champion ‘rights to development’ to advocate for stronger Indigenous property rights either by making them inclusive of commercial rights, at best, or by making them the equivalent of the free prior informed consent rights proposed by Justice Woodward and embedded in land rights law nearly 40 years ago.
Such advocacy might see prospects for Closing the Gap enhanced for those Indigenous people who prioritise development in the mainstream while simultaneously enhancing livelihood prospects from alternate forms of development for those who choose otherwise.
As the Broome Communiqué of May 2015 noted there are tensions between cultural matters, environmental protection and development objectives. Stronger native title property rights are a potentially important means to ameliorate such tensions.
A version of this article was published in Land Rights News Northern Edition August 2015/Edition 3.
1 This month
of the week – Disrupting War & Militarism in Oceania. Active solidarity. Radical practice.
Antinuclear 