South Africa’s first Bio-Climatic family home

The Producers – Michelle & Riaan

With a love for the environment and all creatures within, celebrity Eco-Couple Michelle & Riaan Garforth-Venter pioneered the building of South Africa’s first Bio-Climatic family home.

The most ambitious aspect of the house that the two Earth Hour Ambassadors built in Avianto Estate, a new eco-development in Muldersdrift, is their intention to be completely off the National electricity grid. As a qualified nature guide Michelle is deeply concerned about the state of the Planet and making a difference starts at home.

The Show

Their desire to ‘walk their talk’ has resulted in yet another TV first as the Garforth-Venter’s chose to document the build & produce a 30-part reality series on DSTV’s Channel 182 The Home Channel – inviting viewers into their daily lives and relationship, revealing how they juggled their busy careers and schedules while building and furnishing their first bio-climatic family home, in a reality TV show format. And mid-way through production, the couple welcome their first child Rainn Ashton

A few Clips from the Series

We Re-Thought Everything



What is SANS-204?

This standard addresses the Planet’s energy crisis and specifies the design requirements for energy efficiency in commercial & residential buildings with natural environmental control and artificial ventilation. It concerns all construction aspects of building, foundations, fenestration, walling, glazing, roof and ceilings of all future builds. This standard specifies the design requirements for energy efficiency in buildings with natural environmental control and artificial ventilation or air conditioning systems

What is the Green Star Rating

Climatic-house is not just about energy efficiency. The Green Building Council of South Africa had just completed the first Green Building RatingTool. It was the rating tool for offices, but we used it as a green guide for our house anyway.



Riaan & Michelle’s house is rated by Lisa Reynolds, the Sustainable Development Director for Saint-Gobain. Lisa is the Chair for the SABS Working Group that wrote SANS 204 (and SANS 10400-XA), & serving on the Regulatory Advisory Board for the drafting of the Energy Efficiency Regulation. Ms. Reynold’s was a member of the Technical Working Groups that drafted and published the Green Building Rating Tools for Offices and for Shopping Centres. Saint-Gobain is a Founding Member of the Green Building Council of South Africa. Lisa Reynolds

Chair for SABS, Saint Gobain

Reduce, Re-use, Recycle & Re-Think it

Bioclimatic House Features

Our beautiful home is built in a temperate interior climatic zone 1, namely the Muldersdrift area closer to Pretoria.  One of the challenges in the zone is the huge temperature variation from a cold winter’s night into the temperate winter’s days; only to plummet as soon as the sun goes down. With this is mind, we tried to incorporate as many of the principles of passive design as possible.

green house 2The first principle of passive design is correct orientation. Being in the Southern hemisphere, the best orientation is the living areas to be North facing – totally opposite to North America.

Thus, the solar exposure for this specific climatic zone is cornerstone of on-site positioning. We used optimum shading over the windows to allow for the ingress of the warm winter sun, but to minimize the amount of hot summer sun entering the house. The windows were low emissivity glass which also decreased the amount of heat into the building. All glazing frames were made of wood and sealed the home well. The positioning of the glass doors and windows allowed for great, natural cross ventilation, making the house cool and breezy on summer’s days.

green house 4The ceiling was well insulated to contain any heat generated within the house in winter, making it schnuggly comfortable in every room of the house. In summer, this insulation decreased the amount of heat from the blazing sun from entering the roof void. The PV panels on the roof provided the bulk of the energy needed to run this home and all appliances were rated as energy efficient (?) Natural cooling was sufficient and no air-conditioning was required. Minimal heating was needed for winter.

solar-powerThe solar exposure for this specific climatic zone is a cornerstone of on-site positioning. We built our eco-house in accordance with two regulations: Government’s new green architectural guidelines SANS-204 and the Green Star Rating from SA Green Building Council.

We achieved 100% from both entities!

Green materials are materials used in construction that have least impact on the environment and offer the highest level of performance.

Green construction materials have less impact on the environment, require less energy and chemical processing, are more locally sourced to reduce transportation and are either renewable (timber, bamboo, natural fibres, etc.) or highly recyclable. They have superior performance characteristics in terms of thermal performance, maintenance, longevity, stability, strength, and lightness, among others.

lightbulbWhile researching & writing their BOOK and like-titled TV series “GREEN LINE: A South African Guide to green living”, Michelle established an understandable and accessible approach to the complex world of sustainable-living. Most content can be filtered under 4 Pillars:

  • Energy Saving
  • Water Saving and Quality
  • Waste Management
  • Chemical Concerns

Riaan & I retrofitted our existing home extensively, but addressing insulation concerns prompted us to build new. With extensive nationwide research below are tips to assist you building your dream green home.

* Book & TV series – nominated for the David Attenborough ‘International Green Award” for Best Green Education & Awareness Category.


Energy Saving


Water Saving


Waste Management


Chemical Considerations

Energy Saving

True North

Passive design notes optimal true North orientation and makes use of natural light in the abode, enhancing natural air flow for cooling in summer, and noting the arc of the sun for natural warmth in winter

Floor Insulation

30 millimeter thick polystyrene under concrete floor slab; insulation in double-brick walls – as per SANS-204

Low E Glass

A suitable alternative that creates improved insulation in the SA climate to double glaze windows (which are expensive)

LED Bulbs

LED Energy Saving bulbs: interior & exterior


Gas Stove; 1x Gas oven; 1x ‘electric’ or solar feed oven; gas fridges are available for purchase


Saint Gobain: Insulation in floors, walls, ceiling as per SANS-204

Eco Bricks

Brick, paving, concrete, natural local stone used as construction materials. (porous cement mix for exterior floors to ensure rainwater seepage to water table)

Fly Ash

Fly-Ash: a by-product of cement as a result of burning coal is used to bulk up concrete & make bricks, a new green use for tons of fly-ash that is traditionally dumped

Efergy Energy Calculating units

We are able to view our home’s energy usage by the hour with monetary value showing as energy unit of output.

Steele Roof Trusses

Light-gauge Steele roof trusses with wood over-hangs

Double Glaze Windows

Double Glaze Windows in wood frames: the first made in South Africa, including the sizable double volume ceiling to floor length. These windows are now the benchmark for all wooden framed double glaze windows in the country – as per SABS Construction Standards Division

Solar Water Geysers & Photovoltaic Panels

Solar Water Geysers & Photovoltaic Panels for electricity generation – building a CBD that is off-the-grid. *Eskom back-up power will still be required for points such as security cameras and fencing. Eskom rebate to be included for converting existing structures to greener buildings *Heat Pumps are under testing at a second location

Water Saving

Insulted Piping

Insulating hot-pipes

Rain Water Catchment System

3x 5, 000 litre jo-jo tanks re-inforced on the inside with galvanized piping, so that the pressure of the outside soil does not collapse the plastic structure.

Geyser wise Unit

We can monitor & control our geyser’s energy consumption (Love the cell phone communications it allows)

No Grass

Just wild flowers and veld grass.

Duel Flush Toilets

Duel Flush Toilets

Red-Water Gadgets

Installed at all geysers close to the water outlet. This cold water from all showers, baths and basins is diverted to the garden, swimming pool and herb garden before being up-to-speed with a warm temperature suitable for task.

Permeable Paving

Prevents huge run-off into municipal storm-water systems. Rather allow rain water to naturally seep down to water table level – we made use of a permeable concrete mix for the drive-way.

Drip Irrigation

Drip Irrigation System.

Grey Water Recycling

Baths, showers, basins – pumped for usage inot the indigenous garden and for washing cars.

Flow reducing valves

Flow reducing valves on all taps

Water Saving Showerheads

Water Saving Shower heads efficiently utilising water-flow

Indigenous plants

Indigenous plants for a water-saving garden brings bee’s birds and butterfly’s to your garden.

Waste Management

Recycling Bins

Recycling bins.


Vermiculture or composting Wormeries


A chicken run.

Bokashi Compost

Interior Bokashi compost bins.

Compost Heap

Compost Heap.

Veggie Garden

Door-Frame Size Veggie Gardens.

Sink Grinders

Sink Grinders for wet waste disposal through the homes sewage system.

Water-Wise Garden

An Indigenous Water-Wise Garden

Chemical Considerations

Grey Water

Grey water recycling means only using biodegradable bath products and cleaning products that are chemical free. Avoid parabens, phthalates and sodium lauryl sulphate (SLS).

No Toxicity

Products like V.O.C free paint.

Green Articles

Extreme Makeover, Green Edition

Worms are king in Riaan and Michelle Garforth-Venter’s new house. The couple’s unlikely housemates are going to provide essential garden and homes services in return for their favourite meals – butternut and egg shells.

read more

A Home Birth

Michelle Garforth-Venter is no stranger to South African television viewers. In recent years, she has become something of an eco-warrior, championing the cause of endangered species and the environment in series like Wild LTD. Her latest venture pairs her with husband Riaan – himself the star of a number of DIY programmes – in Love & Mortar, which follows the couples trials, tribulations and triumphs as they build a truly green home.

read more

The Bio-Climatic Home

Why do it? With some extra effort on our part our homes can provide us with a space that connects us to the pleasures of the natural world, keeping us in touch with the seasons and providing our families with a buffer against our fast paced lives. Eco-friendly homes...

read more

Accolade Construction

Environmental Site Management

Accolade live their construction beliefs by:

  • Acting with integrity.
  • Exciting our customers by providing them with the best products and service.
  • Treating all people with dignity and respect.
  • Promoting individual creativity and teamwork.
  • Responding to our changing environment with innovation and enthusiasm.
  • Respecting and safeguarding the environment.

Building in a green, energy efficient way.

The Land

  1. Identify Indigenous plants & trees on site. Keep in tact or carefully remove and replant elsewhere with a landscaper
  2. Remove invasive plants & trees and destroy during construction phase
  3. Any trees contributing to the harmony of the house are kept in tact
  4. Remove the Top Soil (good soil) from the construction area and stockpile. Use this as the final layers for landscaping. Avoid chemical spills on piled soil as it will impact plant vegetation
  5. CARBON FOOTPRINT – Excavate by hand where possible – example footprints instead of using a machine
  6. Human & Vehicle traffic – vegetation must only be cleared to provide essential access for construction purposes. Deep furrows lead to excessive soil erosion and can change water run off patterns

Recycling On Site

  1. General Building waste like cement, bricks, paper can be recycled by using as fill to surface bed.
  2. Items such as doors, frames, windows, pipes, gates etc can be reused at other homes or sold/contributed to needy organizations
  3. Organic waste can be used for compost and landscaping
  4. Rain Water Tanks: water can be reused for dust on roads, general cleaning, cement and plaster mixing
  5. Try to employ local suppliers in lieu of importing materials (Carbon footprint)
  6. Purchase re-usable products or visit demolition sites
  7. Establish waste recycling facilities for rubble, paper, metal, plastic, wood, glass etc

Anthony Papageoriou Architects

Architecture Handbook Pictures


The house makes use of natural lighting, LED bulbs; motion detection and day/night switching; solar panelling for exterior, landscape and accent lighting; gas and solar geysers; a central vacuum system and the use of paints with a low VOC content help greatly to give our family a healthier environment.

Our best performance of the building to create a enclosed envelope is to ensure a low U-Value and a high R-Value, preventing heat gain and loss from outside to inside our home.

The use of wind lobbies, typically used in commercial buildings are under-utilised in homes, particularly in areas of extreme weather. These allow access to the home without losing valuable heat in winter. Wind lobbies can also be used in to trap prevailing winds in Summer helping cool internal spaces.

The Green Dictionary

What is the difference between your Carbon Footprint & your Eco Footprint?

Carbon Footprint: This is the tons of carbon dioxide each person emits. This is your personal contribution to climate change.

Eco Footprint: This is each person’s personal land usage during your lifetime. The land & water required to grow the food you eat, the materials, leisure activities, textiles & fuel you make use of – a figure of 1.8 hectares is sustainable for today’s population, but our world’s average is currently living and using 2.2 hectares per person

Stuff you can live without

  1. Disposable pens: Buy a good pen that only needs the ink-well changed
  2. Disposable razors: Invest in a razor that needs blades changed once
  3. Straws: NEVER use a straw

Projected extinction date of the African Penguin is 2030

Almost a quarter of the World’s Mammal Species and 1 in 8 Bird Species are likely to be extinct in the next 25 years.

Set up Meatless Mondays at your home

Meat is the most resource-intensive food on the table

  • A half kilogram of beef needs around 40,000 litres of water to produce
  • Compared to 200 litres for a half kilogram of potatoes

Never buy another plastic bag, use fabric bags

PLASTIC is the Serial Killer of the marine world & the bush


A pioneering project we completed to a true-as-possible green result with ‘partners willing to question the traditions of conventional construction.

Swartland Windows & Doors
Swartland Windows & Doors
Through this project researched and created a design of double glaze windows about a South African first of double-glaze windows with wooden frames – aluminium metal frames being a poor insulator.
Read More
A rule of thumb is to insulate the ceiling, however insulation in the floors and walls is vital. In Climatic Zone 1, SANS 204 reccommends 40mm thick polystyrene built into cavity walls and flooring – creating a ‘cooler box’ and airtight effect.
Read More
La Farge Cement
La Farge Cement
La Farge are all about sustainability, using Fly-Ash, which is a waste product from burning coal. The green ethic is to reduce their use of non-renewable resources, reduce carbon emmisions during manufacture and cut back on what is being sent to landfill sites.
Read More
Franke Kitchens
Franke Kitchens
We chose to build with baked-clay brick similar to how our forefathers made homes. We investigated the green practises of the company, such as their rejuvenation of quarry sites, usage of rain water catchment & factory recycling programmes to their ethical employee practises. Packing and delivery are improved by eliminating plastic wrap for bricks delivery…
Read More
Cobra Taps and Solar Geysers
Cobra Taps and Solar Geysers
Accolade Construction
Accolade Construction
Accolade attend to clean building site practises, understand local and environmentally sustainable materials as well as insulation knowledge as applied to a variety of sized structures. Keith van der Linde, CEO told me “green building is about equal parts science and ethics, but mostly it’s about common sense!”
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Contact Person

Peter Unsworth

Founder & CEO

Cape Town, South Africa
Tel: +27 21 419 2390/1
Website: www.theprteam.com
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