As the global threat of climate change increases and the availability of the planet’s precious natural resources decreases, a growing number of people are doing everything possible to live in a more sustainable manner. So what better place to start than in our own homes?
There are many things that you and I can do including using less water; creating less waste; paying closer attention to conservation on all levels; avoiding the use of fossil fuels wherever possible; and using environmentally-friendly products as much as we can. Of course if you are planning to build your own home, you should embrace all these issues and go green from the very beginning. But what does building a green home entail? And are you up to the challenge?
There are some simple answers to these two questions, and also some that are quite complicated. But essentially what it means is that you will look at enviro-friendly materials in addition to enviro-friendly methods of building. You will also build in such a way that when you move into your new home, you are able to use less water, create less waste, conserve what is precious, and use energy produced by the sun or wind instead of coal (if this is indeed the energy option you are given by your local authority). There is more of course – never less.
Environmentally friendly home building
There are a variety of factors to take into consideration when choosing building materials that are environmentally friendly. In essence these relate to reducing our carbon and water footprint on earth and improving the efficiency of both resources and energy. There is no doubt that the production of construction materials (particularly cement, lime, bricks, glass, plastics, and traditional paints, sealants and wood preservatives) contributes to toxic pollution. But on the positive side, we can do something about it.
According to thinkstep AG (www.thinkstep.com), sustainability experts with 16 offices worldwide, the building sector has the greatest potential of all sectors to reduce CO₂ emissions and reduce the use of precious non-sustainable resources. While their focus is primarily on commercial and industrial properties and large building construction, there can be a major ripple effect within the home building industry. Similarly various standards (including the Toronto Green Standard, LEED and Green Globes) that have been established to improve environmental sustainability within the building industry should be implemented, not just by large construction companies, but by home builders as well. This means that home owners also need to be informed.
Furthermore it isn’t just the materials themselves that we need to consider – although this is terribly important. It is also the impact of production and delivery to site which needs to be addressed. It is for this reason that it is good practice to use not only “green” materials and products when building, but to also use local materials wherever practically possible. It stands to reason that anything that has to be transported long distances (be in by road or in the air… or even by railroad) will immediately add to the carbon footprint.
It is also preferable to use products manufactured by companies that are proactive in terms of sustainability – and happily a large number of them are. Just one example is All Weather Windows (www.allweatherwindows.com), an Edmonton-headquartered company that specializes in energy efficient windows. Winner of the 2010 Energy Star Window Manufacturer of the Year Award, the company is strongly committed to green options. Apart from focusing on conservation conscious window designs, the company:
- recycles its cardboard and uses it to produce cellulose fiber insulation and other products,
- recycles the cut-outs from all its polyurethane-insulated door panels, using them for various insulation applications in the agricultural sector,
- recycles thousands of pounds of PVC on a daily basis so that it can be used to make PVC deck and fencing products, and
- recycles all its scrap metal.
They are also hugely energy conscious, using waste heat from the heat ovens they use to make sealed glass to heat the manufacturing plant, and they only use high efficiency lighting. These are all actions that work in favor of the environment rather than against it.
But what in fact makes products environmentally friendly?
Ensuring products and materials are environmentally friendly
When choosing environmentally friendly materials and all the other products we need to build our homes, we need to feel secure in the fact that they really are what they say they are. There are two ways you can go:
- You can look for materials that are going to ensure your home is going to be a sustainable haven, or
- You can simply build using materials that have been declared sustainable.
The ideal, of course, is to combine the two, but be warned … it will take a bit of work for you to achieve the ideal. So if you really are sincere in terms of wanting to create something that really is sustainable, and you really are forging a path towards building a green home, then you will want to explore every possible option. Extensive research prior to building is essential. A good way to tackle this is to combine your green research with your compilation of a schedule of finishes and costing. After all you’re going to be shopping around anyway, so why not spend a little extra time checking out green capabilities to ensure your expectations will be met? Considerations will include:
- the building method you use – remembering that lumber is at the heart of the conservation issue,
- materials for heating and insulation, including the roof covering,
- interior finishes, including paint,
- alternative forms of energy and wastewater systems.
Of course each of these opens up a realm of possibilities and options, and it might be easier to find a designer or even a builder who has experience and commitment building green. For example FORT Architect Inc. introduced a new sustainable design concept to the public just two years ago, steering away from traditional timber-frame homes. Sure there’s wood in their houses (quite a lot of it), but wood frame homes use as much as eight times less energy to heat and cool than those constructed with steel or concrete products. In addition, they’ve come up with a system that incorporates a range of conservation strategies. These are clearly top class because the concept they have launched resulted in them being awarded first prize in a Canadian architectural design competition that aimed to find a prototype for leading edge sustainable design in 2009.
Their target market was home builders, specifically those living in the suburbs.
Starting with the idea of minimizing waste and improving efficiency, they came up with the idea of using what they call “building blocks”. They designed 26 “modular blocks”, all of which may be combined in different ways to create homes with anything from two to seven bedrooms. Using this imaginative mix and match system, they introduced a unique way to improve both affordability and quality control. Furthermore they focused directly on the LEED (Leadership in Energy and Environmental Design) green building rating system ensuring that all houses built according to their specifications will meet the standards set for LEED-platinum, the highest rating possible.
In Canada the LEED rating system is operated by the Canada Green Building Council (CaGBC) which, since 2003, has been working hard to ensure buildings have a sustainable future.
FORT Architect’s homes also meet the international Energy Star standards for energy efficiency. They incorporate passive solar design, top notch insulation, and they are built using durable materials, many of which have a high recycled content. They specify and use only FSC certified wood, install low-flow toilets, use both double and triple glazing for doors and windows, and even specify “recycled paint”. They are hot on renewable energy, water efficiency (which includes grey water and rain water harvesting), waste heat recovery, innovative wastewater treatments and advocate the planting of drought tolerant plants that are native to your area. These are the things that really do matter if you are building a green home.
Sustainable building methods
Different building methods are favored in different parts of the world, which means that materials used for building also vary. The most popular building methods for domestic houses in both first world and developing countries include timber frame and bricks and blocks that are laid using mortar. Concrete footings and foundations are required for both.
But there are many other methods, some that use steel, and others that rely on concrete products. When it comes to the manufacture of these broadly defined construction materials, there is no doubt that lumber is the most eco-friendly option – in spite of deforestation being a major environmental issue. The reason is that it takes more than 50% more energy to make steel products for building than those made of wood. It takes more than double the amount of energy (up to 120%) to make some products that are made from concrete. Furthermore, both steel and concrete manufacturing processes result in very high emissions of CO₂.
Concrete is, of course, made using cement and a mixture of coarse and fine aggregates (crushed stone, sand and so on) which are combined with water to give it strength. The shocking part is that cement production is one of the worst culprits when it comes to greenhouse gas emissions. Even though not even 15% of the concrete mix is cement, other factors to consider are:
- the mining of the aggregates used,
- the fact that a lot of water is used, and
- the fact that the manufactured product usually has to be transported quite long distances.
In addition, if the concrete is reinforced, it will also have a fair amount of steel in it.
While timber frame construction is favored in North America and Australasia, twice as much concrete is used for building construction throughout the world than all the other materials put together (including wood, steel, plastic and aluminum).
But if timber is to be used, it is vital that it is sustainable.
Green wood for building
An awful lot of wood goes into building houses in North America, and so this is an area that demands a lot of attention when we talk about going green.
First and foremost, FSC certification is a must (ic.fsc.org). An international organization established nearly two decades ago to promote the responsible management of the world’s forests, the FSC (Forest Stewardship Council) certifies forests that are environmentally acceptable – meaning that they are sustainable. There are several other organizations that certify wood, and the Canadian Standards Association (CSA) keeps a handle on these worldwide – www.csa-international.org.
But it isn’t enough for wood to come from sustainable forests. If laminated products are used – be they beams or flooring – it is essential that they aren’t manufactured using toxic adhesives. It is also important that sealants and varnishes are non-toxic too.
Of course another green wood option is to use old wood that has been salvaged, either from old buildings or from companies that specialize in recycling building lumber. There are a number of these in North America, including the Canadian Heritage Timber Company (www.canadianheritagetimber.com) that has been rescuing old building wood for more than a decade. They re-mill it so that it is suitable for a range of uses including hardwood flooring, fireplace mantles, and stair treads. Second Wind Timbers, another Canadian company, produces an even larger range of recycled timber building products. In addition to flooring and decking, they manufacture both entry and interior doors as well as structural lumber for timber frame homes.
It isn’t only old building wood that is recycled, several companies reclaim lumber from rivers where it fell long ago during the logging process. Logs End (www.logsend.com) for example mills and crafts wood that was felled generations ago, but which has been lying under water in the Ottawa River, perfectly preserved. They also harvest from environmentally friendly, well-managed forests that are FSC-certified.
Then there is another equally important issue when it comes to building a green home – the chemical treatments used to preserve wood.
Preservation and treatment of timber
All timber used for construction should be graded and treated to make it resistant to insects, fungus, mould and so on. The question is what sort of preservatives are used. Until relatively recently, the best option was probably pressure-treated lumber.
The American Wood Protection Association (AWPA) is responsible for wood preservation standards. Until 2003, the most common wood treatment was chromate copper arsenate (CCA) – administered under pressure – which contains arsenic. AWPA put a stop to the use of CCA in the US, and since then copper-based pesticides have been used there, although CCA is still used in many other countries.
In 2006 a company called New Wood Global was formed in Vancouver, Canada to source and market what they termed “advanced wood protection products”. They discovered an amazing product line called BluWood and bought the rights to it from WoodSmart Solutions in Florida, USA. New Wood Global became BluWood International and then Nexgen Protection (www.nexgenprotection.com) and continued to promote this extraordinary two-part, trademarked, wood treatment product that provides what seemed to be the ultimate protection against mould, fungus and insect infestation.
Now they have produced the next generation of BluWood protection – BluWood NexGen (also trademarked). Timber in covered structures has a lifetime warranty for mould, mildew, rot, fungus and insects (including terrible termites). Because there is a tough UV-blocking agent in the new product, there is also a 30-year exterior use warranty on all outdoor applications including sidings and cladding, shingles and shakes, as well as fencing and decking.
The product is applied in the factory either as a clear coat or a custom-tinted color. It works on all wood species and laminates. No harmful VOCs are added to the wood, there is no off-gassing, and there isn’t any leaching of harmful chemicals. Better still, it can be used as a primer since both paint and stains can be applied over it.
It gets even better. BlueWood NextGen ADVANCED also has a fire inhibitor that upgrades the lumber from a Class B fire inhibitor to a Class A. This is the same classification that concrete has. The additive used is a registered “green” product that is used to protect many other products including clothing and mattresses. It is fast becoming the material of choice for all framing materials in North American construction. With offices in Europe, South America and the Asia Pacific region, it is also making an impact in other parts of the world. It would seem that blue is truly green!
Alternatives to wood
There are, of course, alternatives to wood when it comes to building materials. These range from metal (including both steel and aluminum) which as previously mentioned can be used structurally, to bamboo which is becoming increasingly popular for flooring. Concrete roofing tiles may also be used instead of cedar shingles.
The leading producer of bamboo flooring in North America is Smith & Fong (www.plyboo.com) and their selection of products is impressive, incorporating as many as 75 solid and plywood finishes.
Like wood, bamboo should have an FSC certification so that you are assured it comes from a bamboo plantation that is truly sustainable.
Smith & Fong also produces flooring made from palm trees, another green option worthy of consideration. While it is relatively expensive, its sustainability is unquestionable since it is made from non-productive palm trees that were originally planted for their coconuts.
While your roof covering will depend on both the structural design of your home and budget, there is considerable choice in terms of materials. One Calgary company that manufactures both concrete roof tiles and fiber cement sidings is Unicrete Products Ltd. Not only are these tiles economical, but they are also reasonably sustainable and may be fully integrated with solar panel systems. The company also encourages home owners to install roof tiles using their Ener-Vent roof installation system to maximize energy. This provides air vents and optimizes air flow under the tiles reducing the potential for ice to dam in winter and improving overall energy efficiency. Taking the downside of concrete, it becomes a case of swings and roundabouts.
Energy efficiency
Energy efficiency needs range from insulation to heating and effects walls, floors, roofs and ceilings, doors and windows, and of course hot water systems and power generation. The subject is huge, but there are numerous specialists who are ready to advise new home builders, which is just as well since this really is an essential aspect of building a green home.
Solar energy One solar electric specialist in Canada is Home Energy Solutions (hespv.ca), which supplies a range of different products including fully code compliant off-grid solar heating kits. They can also assist with grid-tie inverters and the MicroFIT program for Ontario homeowners who get paid for solar electricity they generate that is then delivered to their utility provider.
There is no denying that solar is smart, even in countries that suffer from severe winter weather conditions. Quite simply, it is a sustainable energy system that is based on a renewable energy resource. What could be better?
Generally the first step people take is to install a solar water heater. But now more and more people are going the whole hog and using solar power for electricity as well. In most parts of the world, governments and local authorities offer rebates and incentives that encourage more and more people to take the step to solar.
A basic solar-powered system requires just a few basic components including solar panels, a solar regulator, a battery and an inverter to convert the electricity from direct current (DC) to alternating current (AC) that we can use to power appliances and tools. AC is basically like the electricity we get from the utility supplier, while DC is what batteries need to operate. Solar panels are what we call photovoltaic meaning light (photo) + electricity (voltaic); and what happens is that the panels extract light from the sun and quite simply convert it into DC electricity. This is channeled though a solar regulator to the battery or a bank of batteries. A power inverter then converts the DC power into AC electricity.
Once you have installed a solar heating system, you can save as much as 40% of regular electricity grid costs. Better still, it’s green. However it is true that solar energy is variable, depending on weather and season. For this reason you should have a generator that you can use as a back-up during winter. Alternatively make sure you have a larger-than-normal battery bank and consider the wind turbine option as well.
Wind turbines While the wind turbine option hasn’t yet caught on quite as much as solar, it can be very effective, particularly where there is a lot of wind – since the more wind there is, the more electricity you will generate! Having said this, if you live in an area that is prone to hurricanes, you’ll need to lower the turbine if there is a hurricane warning.
Essentially a wind turbine works the opposite way to a fan, and it uses wind to make electricity in a generator. There are various factors that influence the amount of electricity you can generate this way, including the height of the turbine tower and the size of the rotors. This will obviously affect cost, but the two generally balance out in the end.
Like solar power, wind turbines may be connected to the grid but they don’t have to be. However to produce electricity they should be connected; those that aren’t generally used for charging batteries – great if you need it to charge batteries for an electric car. Wind Energy Solutions Canada (WES Canada), a subsidiary of a Dutch manufacturer of wind turbines, maintains that their system can save up to 90% of fuel costs.
Having sorted your energy source, you need to consider insulation issues. After all if glazing isn’t energy efficient and you lose heat because you don’t have adequate insulation in the building, then you’re going to need more electricity in whichever form it is available.
Glazing and insulation We build our homes so that that are weatherproof and can be made airtight – or at least reasonable airtight. Within this context, we use various materials to ensure thermal insulation. Generally speaking, there is a “thermal envelope” which is the living space within any house. Sometimes we include the attic or basement of the house in this space, sometimes we don’t. But however the house has been designed, the important factor is to prevent heat loss or heat gain to and from the building. Once the house is airtight, a system must be available to manage the air.
A house that is badly insulated will be cold, damp and directly under the roof (in an attic for instance) unbearably hot on sunny summer days.
Our houses incorporate different types of insulating materials, depending on function. Some have low thermal conductivity while others are primarily effective at blocking heat radiation, while others (like foil-faced rigid panels) can reduce heat transfer in various ways. But for a product to be green, it needs to be eco-friendly, as well as safe and unhealthy (or rather not unhealthy).
More than a decade ago the North American Insulation Manufacturers Association (www.naima.org) introduced a voluntary work practice partnership with the US Occupational Safety and Health Administration (OSHA), primarily to promote the safe handling and use of insulation materials, primarily fiberglass, rock wool and slag wool products. But this doesn’t necessarily make them green. Eco-friendly products include those made from recycled paper and several others that are listed at www.greatgreenlist.com.
When it comes to windows, in cold-climate countries like Canada, it is essential to have double or even triple glazing. In countries that experience a great deal of heat, like most of South Africa, single glazing is the norm. Even so it is best to use quality glass that blocks ultraviolet light when it’s hot, and benefits from solar gain. This means that the window pane will retain heat and not transfer it out of the window. The other factor to consider is how much visible light is transferred through the panes. About 5% of visible light is filtered naturally. Clear glass with no coatings will allow about 90% of visible light to enter. Triple glazing with an ultraviolet sun stop coating may only allow 40% to 60% of visible light to filter through. A company like All Weather Windows will be able to give you the full specifications so that you or your designer can make an educated choice. Another is Cascadia (www.cascadiawindows.com) which produces windows with fiberglass frames and high performance glazing. Th
eir products meet or exceed the Energy Star criteria, which is a very important consideration when building a green home.
Environmentally friendly paint products
Paint is another building orientated product that has been targeted by advocates of green buildings, primarily because of the VOC factor. Happily a growing number of companies are now producing eco-friendly products including Benjamin Moore (www.benjaminmoore.com).
Or you could hire an eco-friendly paint company like Element Painters Inc (http://paintcanadagreen.com) to do the job for you.
Of course there are many other details to consider when going green. This is just the beginning.
