The many shades of green

Stand 47’s efficiency and innovation concepts drive the vision to achieve a quality home that embodies state-of-the-art principles for style, comfort, and efficiency both during construction and later in future use. Although it is not the direct intention to make Stand 47 a ‘green building’, a consequence of many of the decisions made during Step 1-3 of our process is that through the efficiency and innovation concept, we have been able to achieve many ‘green’ principles. This demonstrates that while Stand 47’s main concept was not to be ‘green’, following the process from concept to design to specification has led to many strategies in Stand 47 that are also ‘green’, such as passive design (orientation, cross ventilation, natural lighting and shading), alternative energy sources (heat pumps and PV panels), future-proofing (easily altered interior plan)  acoustic and thermal efficiency (range of Saint-Gobain products and light steel frame construction) and rainwater harvesting.

A benchmark that could be used to gauge the ‘shades of green’ that Stand 47 embodies, is that set up by the Green Building Council of South Africa. As stated in their website “The green building movement addresses what are becoming the major issues of our time: excess energy consumption and the related CO2 emissions from burning carbon fuels; the pollution of air, water and land; the depletion of natural resources; and the disposal of waste. Green buildings have lower operating costs, are more efficient, future-proof, provide a higher rate of return and have been shown to promote wellness, healing and productivity.” Using the Green Star rating tools (Multi-unit Residential, Public & Educational, Office, Retail and more recently, Existing Building Performance PILOTInteriors PILOT and Socio-economic Category PILOT), buildings can be assessed, achieving the maximum rating of 6 stars either during design phase or after completion. 

Tenth site meeting

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With the roof sheeting having been installed over the main structure and outbuildings, it is possible to get a feeling for the scale of the internal spaces that will make up Stand 47.

On site, construction progresses as weather conditions allow; the retaining walls continued to be clad with stone obtained from a local quarry while the ETICS walls are going up at a steady pace. 


Interior space – the clerestory window frames the trees & the overhang

Stone clad walls

After the first rains…

After the first rains, the golden hues of winter have transformed into the bright greens of summer, marking a magnificent metamorphosis of the Monaghan Farm landscape, wherein the discreetly positioned Stand 47 has also been experiencing its own transformations. All the structures now have roofs, and work can continue in the interiors despite the possibility of further rain.
Embedded within this landscape, the roof over the main living areas of the house appears to be suspended in the air, providing shelter for the spaces below, while the natural rock walls appear to anchor the house within the site from which it extends.

Building regulations – burden or benefit?

Most home owners planning renovations to their property or own home builders, are confronted with regulations that stipulate what they may and may not do. In many cases these regulations are a source of frustration since many of the limiting restrictions are not apparent upfront. 

These regulations are usually in the form of title deeds, zoning as well as the National Building Regulations. Broadly speaking, a title deed, stipulates the ownership of a property, and includes the rights and obligations that pertain to the property. Land-use and zoning is decided by the municipality’s town planning departments and controls the heights, coverage and setbacks a building must adhere to, as well as its functions (eg. residential, commercial or a mix of uses). Thirdly, the National Building Regulation (NBR) maintain the standard and quality of construction (and hence the built environment) in South Africa. It is in the pursuit of quality and excellent, that the building regulations are a benefit: since all properties should by law conform to these regulations, the collective value of our built environment improves. 

New building regulations overview

The NBR is established by the South African Bureau of Standards (SABS), whose mandate includes the development of the South African National Standards (SANS) and others, covering a spectrum of products and services, such as those which regulate quality control in the built environment. 

For the purposes of building a home, the building regulations consist of a number of parts that together comprise SANS 10400. These include (among others) regulations for dimensions, structural design, public safety, excavations, foundations, floors, walls, roofs, accessibility and fire safety. 

In the last few years, the SABS have responded to the growing pressure from development on limited environmental resources by adding new part, SANS 10400-XA, which are the deemed-to-satisfy rules that deal with energy usage in the home as well as SANS 204 which are the guidelines that look at how to achieve energy efficiency. This is done through passive design strategies including orientation towards north, window sizing and positioning, shading, materials (thermal and insulation properties), solar heating, natural cooling and daylighting. 

Summary of a few key areas of SANS 10400-XA:

  • Windows – the total fenestration area cannot exceed 15% of the floor area unless the design can accommodate alternatives that demonstrate that heat will not be lost. This could for example be through the glazing specification, materials, insulation, or roof overhangs, which is the case in Stand 47.
  • Roofs – The minimum R-Value of an assembled roof structure is roughly R3.7 depending on the climatic zone. There is a substantial difference between the roof structure and cladding, meaning that insulation like Saint-Gobain’s aerolite, become necessary.
  • Walls – Non-masonry walls like the ETICS walls being used at Stand 47, must achieve a minimum total R-Value of R2,2 or R1.9 depending on the climatic zones. The ETICS Wall system from Saint-Gobain has an astounding R3.76 R-Value.
  • Artificial lighting – Plans must now specify light levels, energy demand and energy consumption in the lighting plans. Stand 47 have specified low energy bulbs throughout the house, and using their electrical consumption calculations have specified Photovoltaic panels to run the household, supplemented by grid-electricity when necessary.
  • Geysers – 50% of all hot water in new builds must be sourced from alternative energy, not grid-electricity. Therefore, hot water must be supplied by either solar water heating systems, natural gas or alternatively a heat-pump. In Stand 47, gas and heat-pump options were explored.

Site progress – stone wall cladding

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Stand 47’s architectural narrative, which is essentially that of a light techtonic shelter emerging from the heavy stereotomic walls that anchore the building within its landscape, is starting to be articulated strongly in the latest phase of construction. The masonry retaining walls that mediate the site boundaries and the broader setting at Monaghan Farm, are now being clad with natural stone, to further emphasise this narrative and develop the aesthetic of a light building rooted to the land. 

Site progress – roof & wall cladding

This week started off with a few key components giving life to the Stand 47 project and marking yet more tangible construction progress on site. The addition of more ETICS wall panel systems and their plaster, the further installation of the roof structure over the main living areas as well as roof sheeting over the garage and domestic unit, is starting to create a realistic impression of the future form of the house in its setting, and the spatial quality within the structure as well as the spaces between buildings.

Etics walls – a close-up gallery of photos

On the 19th of September we featured a post on the ETICS wall cladding system. Below are a few photos of the installation of the product on masonry and light steel, showing the EPS panels, to Isover insulation, mesh reinforcing and the plaster render.

Roof structure + cladding

With roof trusses, purlins and beams manufactured off-site, the assembly of the roof structure occurs relatively quickly, followed by the installation of the roof cladding. Without having to depend on the traditional process of masonry walls needing to be built to wall plate height before the trusses and roof cladding can go up, the external and internal walls here can be clad in parallel to the roof structure, also meaning that internal work can continue once the roof cladding is up without delay during the rainy season.

Insulating Stand 47 using isover products

Why insulate?

Insulating a building makes good sense. While it been considered a luxury for a long time, it is now becoming a necessity for economic and environmental reasons. These two main motivating factors mean that for a minimal cost, insulation saves a lot on annual energy bills over a long period of time (making it really favourable in South Africa where energy costs will keep rising); and they also mean that the energy consumption demand at source is decreased as is the demand for the earth’s precious non-renewable energy resources. Stand 47 will be using Saint-Gobain’s Isover insulation products, including the geyser packs, pipe-packs, cavity-batts, SAGEX EPS and ceiling insulation, to ensure that the highest thermal quality is achieved.

How does it work?

Isover’s properties are used to “slow down” or “resist” the flow of energy such as heat or sound. Its thermal insulation provides a high resistance to the flow of heat from a warm surface to a cold surface and thus limits the impact of the outside temperature in disrupting a comfortable living environment. These properties are very effectively demonstrated in two areas of thermal insulation design: ceiling insulation and hot water systems.

Striving for excellence

After the National Building Regilations (NBR) were updated in 2011 to include Part X and XA for sustainability and energy efficiency, Isover’s insulation products have proved their value once more. Isover’s Ceiling Insulation, Think Pink Aerolite has a variety of thicknesses for each climatic zone that comply with SANS 10400-XA. Isover’s Geyser Pipe Insulation Pack consists of six 1 metre Glasswool snap on pipes which achieve an R- value of 1.00 which is required by SANS 10400-XA legislation. In addition, Isover’s Geyser Insulation Pack exceeds the requirements laid out in SANS 10400-XA.

Did you know?

  • To properly insulate a ceiling and geyser system in a typical home costs less than 1% of the total per square-metre building costs and positively influences 63% of the electrical consumption, therefore reducing energy bills considerably.
  • By installing insulation, the building’s thermal comfort is improved not only in winter by reducing the energy consumed for heating, but also in summer for cooling.
  • Insulation also provides acoustic comfort and reduces noise transmission.
  • Insulating hot water pipes can save up to 37% of the energy used by the geyser system, offering a payback period within 6 months.
For more information about the thermal insulation systems available from Saint-Gobain’s Isover range, please go to their website or download the brochure below:

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Saint-gobain site visit

Saint-Gobain‘s commitment to innovation and product excellence was illustrated during a site visit to Stand 47 today. Local product experts from the various Saint-Gobain departments as well as two international directors, were invited to examine progress on site and to observe the seamless integration of many state-of-the-art Saint-Gobain products that have never been used in a residential application of this kind before. 
While on site,  there was a healthy conversation around the technological issues and public perceptions that this project is trying to demystify through a process of creating public awareness and by providing a practical example. General consensus remains that the Stand 47 case study is a means of demonstrating to the public an available alternative for residential construction in South Africa, that is not only efficient, faster and more practical to build, well designed and rooted to its context, but is also a means of highlighting the high quality building materials and technologies that are readily available locally, but up to now have been under-utilised by the market. 

The roof structure is up

This week has seen the start of a substantial development on Stand 47, with the installation of the steel roof structure (that arrived on site in pre-manufactured panels of trusses and purlins). This new step in the construction phase has given immediate rise to the form of the house which will soon allow for the roof cladding to be attached to the structure. The gentle pitch of the roof with its long and elegant overhang, already provides some tangible signs of the spatial qualities that will characterise the house.