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Increasing Sustainability over Time

A new home should have the capacity to adapt to varying levels of sustainability without sacrificing

value although working within a realistic budget. Attention is placed on how to enhance value through

sustainability when the home is initially completed, and importantly how the new home can adapt to

changing needs of sustainability.

Most people naturally assume that the current standards of new construction and the buildings codes are

the best standards that we could possibly build, in actual fact this is not the case. The current standards

embodied in the Australian building regulations are the best we have had but they certainly do not

represent the best possible standards and sustainability only became part of the building codes in 2004.

Moreover the current BCA only covers sustainability issues such as energy efficiency and there is a lot

more that it could conclude for example, water efficiency and durability issues.

For example take energy efficiency and conservation, it is possible to construct housing with walls and

roof that conserve much more energy than those built under current BCA standards, but we don’t – why

is this? Partly it is down to cost – yes it is possible to build walls and roof that leak less heat and

‘coolth’ (cool air) and that have much better inherent characteristics of heat retention and so on but it

would cost more to build and possibly add time to construction periods too. With housing affordability

as a key economic issue in all states – there is little driving the call to increase standards and make

housing even more expensive especially to first time buyers.

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So now we realise that even our new homes could be more sustainable, what can we do?

Sustainable options for new homes

A new home should have the capacity to adapt to varying levels of sustainability without sacrificing

value although working within a realistic budget. What is a realistic budget? Research tells us that

most people will stay in their home on average for about 7 years or so before moving elsewhere. When

you adopt any sustainability measure you will benefit from day one – whether it is to introduce more

insulation in your roof space or putting in a rainwater or grey-water tank you will benefit. The benefit of

the insulation is a warmer home during the winter months and lower energy bills whereas provision of

water tanks would mean you could retain or create a garden that water restrictions prevent you from

having as well as reducing your water bills. In order to benefit you have to pay for the item and so a

cost is involved.

There are a couple of ways of looking at this - one way of looking at what’s realistic is the payback

period and also maintenance of the item and durability (how long will it last?). If an item costs $900,

lasts 10 years and costs say $100 in maintenance over that time and saves you $100 a year then the pay

back is 10 years. The other way of looking at this is the added value to your property. If you invest the

$900, you benefit from the $100 a year savings from day one but you may add $5,000 to the value of

your home.

How you can add more value than the item costs?

Well if you have already made the improvement you are or have saved someone else the bother of

doing it. Think of all the research time spent investigating which is the best water tank to buy, where to

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locate it, organising the installation and so on – there are a lot of hidden costs to you in making home

improvements which is why others will pay for the benefit of not having to do it. Of course it is very

hard, some say impossible to actually breakdown exactly how much individual items add to a homes

value but each improvement you make that makes your home better than others in your area will add it

its desirability and this will lead to higher levels of interest when the property comes to be sold.

What this means is that your improved home will attract more interested buyers, which in an area where

auctions are the predominant method of house selling will almost certainly inflate its value.

Furthermore if you live in an area where auctioning in not the preferred method of selling you will

almost certainly sell your house more quickly and where blind bids are submitted people will pay more

to secure the purchase. In effect what you are doing by making these sorts of improvements is adding

pluses and removing negatives in the eyes of the buyers. The buyers are able to justify paying that little

bit extra at the point of purchase because they will argue that the costs of occupying or living in the

house will be lower than other similar properties without the sustainability measures.

So how do you enhance value through sustainability when the home is initially completed?

Energy conservation

Well of course any purchaser of a new house is reluctant to start ripping things out so let’s start by

looking at a range of low cost low impact sustainability measures you might consider in your new

home, starting with energy consumption. The lowest cost measure you can take is to install low energy

light bulbs into the fitting – this will reduce energy consumption, reduce the heat load in the home and

save money. Unfortunately it is unlikely to add any value to your home though. Therefore it may be

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worth considering some of the more expensive options at an early stage so that you actually benefit

from the measure in terms of usage and enhanced comfort as well as the added value to your property.

Table 1.1 below identifies a range of measures and also the general suitability to different housing

types. The level of impact is also indicated in the fourth column, here the level of impact is the

sustainability impact the measure makes, so for example the introduction of roof insulation has high

impact reducing energy and greenhouse gas emissions. The cost column indicates approximately the

average overall cost of implementation of the measures into low, medium and high categories. The

average overall cost of implementation includes capital, installation and maintenance and repair costs

for the average life expectancy of the measure. You must be aware however that costs will vary from

state to state and readers should always investigate all costs thoroughly before making any

commitments to improvements.

The final column indicates the life expectancy or durability of the item and is categorized as short (up to

5 years), medium (5 to 10 years) and long term (over 10 years). Housing types have been categorised in

the following ways; detached house (DH), town house (TH), single storey unit (U), high rise apartment

(HR), rural housing (RH), and finally all housing types (A). Table 1.1 shows the different measures

you can consider for new housing that will reduce energy consumption and reduce your household’s

carbon dioxide emissions.

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Table 1.1 – Potential energy consumption sustainability measures for new homes

Sustainability measure – energy consumption

Housing type

Level of

sustainability impact

Indicative Cost level

($)

Life expectancy of the measure

Insulate roof space DH, RH, TH, U High $$ Long term

Insulate timber floors with sub-floor insulation

DH, RH, TH, U High $$$ Long term

Insulate external walls DH, RH, TH, U High $$$ Long term

Insulate windows – film A High $ Short term

Provide internal window blinds to prevent excess heat gain and solar glare.

A Medium $$ Long term

Provide external blinds to prevent excessive heat gain and solar glare

DH, TH, RH, U Medium $$$ Long term

Provide draught stripping to gaps around window and door openings

A Low $ Medium term

Provide new double glazing

DH, TH, RH, U Medium $$$ Long term

Provide new energy efficient boiler / heating / cooling system

DH, TH, RH, U High $$$ Long term

Overclad external walls to provide additional insulation

DH, TH, RH, U High $$$ Long term

Provide solar heating system

DH, TH, RH, U High $$$ Long term

Provide PV array for energy

DH, TH, RH, U High $$$ Long term

Provide wind turbine for energy

DH, RH, High $$$ Long term

Use wood burning or biomass for heat source

RH, DH Low – Medium $$ Long term

Provide low energy lighting

All Low - Medium $ Long term

So now we know the different options in terms of energy consumption and new homes and the level of

sustainability impact each, and the indicative costs involved as well as the life expectancy of the

measure. But what about the added value to the home?

The big issue with some of the measures like, installing insulation in the roof is that you can’t actually

see it! Unless someone tells you that it’s there you don’t know. So if you are selling make sure your real

estate agent is aware of any ‘invisible’ improvements and if you can provide them with before any after

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evidence of the energy savings you have made – save those old energy bills and demonstrate that your

house actually reduced its energy consumption and energy bill by x% or y dollars. This is a powerful

marketing tool which will really affect buyers especially when energy costs are increasing. In some

European countries all homes require an energy rating at the point of sale so that all potential buyers can

assess its energy efficiency – we don’t it here in Australia yet but it could be coming our way in the

next few years.

Generally speaking the low cost items like retrofitting clear film to window openings and draught

stripping door and window openings is unlikely to add much value to your home in today’s market.

However some of the higher cost measures such as solar heating or a PV array is highly visible to

buyers and will attract high interest from the sector of the market which values the environment and

sustainability measures. This proportion of the market is a fast growing sector and as more Gen Y

people move into the property market with the value they attach to the environment the sector is set to

grow even more. Again any evidence you have on maintenance costs and saving that you enjoy from

the measures must be passed onto the real estate agent to ensure that it is included in the marketing and

promotion of your property.

Some measures like the installation of wind turbines in urban settings may deter some people especially

if they perceive an issue with noise from the turbine – if you have fitted a turbine with very quiet

operation then let the agent know so it can be passed onto purchasers. Some measures have dual

benefits for example, double glazing will reduce heat loss and also reduces noise pollution so make sure

both benefits are noted to the agent when they come to make their assessment of value and sell the

house.

The second most important or some say, the most important issue for Australia is water consumption so

what you can do to your new house in terms of reducing water consumption?

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Water conservation

Just like the energy consumption measures above there is a wide range of options available to

homeowners with water conservation measures which range from low to high costs, low to high impact

and short to long term. Table 1.2 below shows the different types of measure you can take with regards

to water conservation, housing type, cost, potential sustainability impact and life expectancy of the

measure.

Table 1.2 – Potential water consumption sustainability measures for new homes

Sustainability measure – water consumption

Housing type

Level of

sustainability impact

Indicative cost level

($)

Life expectancy

of measure

Swap shower heads in a water company initiative* note there may be a limit on the number of shower heads you can swap

A High None Long term

Fit water flow restrictor washers in showers and wash basins

A Medium $ Long term

Purchase low water usage appliances

A Medium - High $$$ Long term

Install dual flush wcs A High $ Long term

Relocate washing machine to discharge into garden or water tank

DH, TH, RH, U High $ Long term

Install small rainwater butt or tank to collect rainwater from roof for garden use and car washing

DH, TH, RH, U Low $ Long term

Remove bath(s) A High $$ Long term

Install larger rainwater tanks

DH, TH, RH, U Medium – High $$-$$$ Long term

Re-plumb the property for a dual water system where grey-water (from sink, showers and wash basins is diverted to water tanks for garden and car washing use)

DH, TH, RH, U High $$$ Long term

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Some options like re-plumbing the property to operate under a dual system will almost certainly,

involve a considerable amount of disturbance to the finishes and fittings of your home so they are not to

be taken lightly. As with the energy consumption measures it is necessary to collect evidence about the

benefits of your improvement when selling your property. Value is added to your home when others

perceive that they too, will enjoy the benefit. For some buyers, probably quite a few – this means you

will need to educate them about the benefits of the measures you have implemented. With water

economy measures pre and post measure bills are a good way of demonstrating the savings in water and

money you have made.

Health and well-being measures

A third area where sustainability measures can be implemented is related to improved health and well-

being of buildings occupants.

What are the measures related to health and well-being they you can implement in your now home?

We have already covered some of the issues previously but we have become more aware over the last

few years of the effects on humans from the toxins and pollution in our homes. This part of the

discussion looks at the measures you can take to improve the air quality in you home, reduce toxins and

pollution, eliminate sources of radiation, improve sound insulation and reduce noise pollution and

create a healthier internal environment.

There is a very substantial negative affect on property values where there are concerns about any

damaging effects on human health – think about the impact on value for properties located near to

sources of contamination or polluting factories. As time goes by more and more evidence is

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accumulating on the negative effects of some of the common materials used in everyday products in our

homes.

It has been estimated that there are around 60,000 chemicals in every day use around the world – some

are synthetic or man made like formaldehyde, while others are naturally occurring like the carcinogenic

radon gas for example which seeps up through the earth and migrates into housing. The amount of

chemicals in your home partly depends on how frequently you clean and redecorate as well as the

products and materials you use. Any toxins and pollutants you remove from your home should be

disposed of safely in accordance with your local authorities’ guidelines. It is likely that a new house will

have that ‘new’ home smell – this is actually all those chemicals and toxins off gassing so leave the

windows and doors open as much as possible to ensure all the chemicals dissipate quickly as possible. It

is very worthwhile; where you get choice of materials in new housing to select those that are as natural

as possible to avoid introducing chemicals and pollutants into the home.

Indoor air quality

To improve indoor air quality there are a number of measures you can take – firstly remove and or

avoid materials with that contain any of the following; asbestos, formaldehyde (found in glues) and air

borne micro-organisms. Bacteria, mould spores and amoeba are often found in indoor air where they

can form colonies and can enter the respiratory systems of occupants. One of the biggest determinants

of indoor air quality is the relative humidity – this is the amount of water vapour presenting the air.

Basically the higher the amount of water vapour present, the higher the relative humidity (RH) the more

likely it is that micro-organism can form their colonies. Mould growth is a manifestation of a micro-

organism colony formation which can lead to allergic reactions in people. Bathrooms, laundries and

kitchens are the rooms which are likely to have the highest levels of humidity and so you should make

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sure they are well ventilated and the micro-organisms can’t form their colonies. Extractor fans or

dehumidifiers should be used in extreme cases. On the other hand if the relative humidity is too low and

the air is too dry – humans will be vulnerable to more infections where the mucus membranes in our

throats dry out. 20-30% RH is considered a desirable level to aim for.

Ventilation is the key to good indoor air quality – where possible doors and windows should be opened

to allow air changes to occur. In this way any toxins can be flushed out and replaced by fresh air. The

number of air changes depends on the size of the room, number of occupants, humidity, temperature,

any sources of combustion, odours, and sources of toxicity. When it comes to selling your property

most buyers are looking for a home which feels light and airy and not stale and smelly. As more people

become aware of and or affected by poor air quality and toxins the issue will go up the agenda – any

parent of a child with allergies or asthma will attest that when looking for a new home health related

issues are top of their buy list.

Sound and noise issues

Sound can be pleasant or unpleasant and this part of the discussion looks at unwanted sound or noise

pollution as it sometimes referred to. Sounds affect our bodies as a series of pressure waves or

vibrations which vary in intensity and frequency. The intensity determines the loudness of the sound

whereas the pitch (how high or low it sounds) is determined by the frequency. The human ear can pick

up a vast range of sounds (measured in decibels (dB)) from rustling leaves at 10 dB to the pain

threshold of loud thunder (120 dB). Normal conversation is about 60 dB and a heavy truck 90dB (see

table 1.3). Extreme sound is painful and can be damaging so we need to ensure we strike a healthy

balance of sound especially inside our homes.

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Table 1.3 Different types and levels of sound

Types of sound Level of sound (Db)

Rustling leaves

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Normal conversation

60

Heavy truck

90

Thunder

120 (pain threshold!)

To control noise in your home we need to understand how it is created and transmitted. Firstly airborne

sound – noise is most easily transmitted when there is nothing blocking its pathway, for example

through an open window or through crack or gaps. You can simply reduce airborne sound by sealing

gaps and cracks. Impact sound is another form which is created by the impact of one thing on another

thing – for example shoes on the floor. Not surprisingly heavy objects and hard surfaces combine to

produce the most impact sound. An easy solution is to use soft floor coverings and or soft shoes in areas

where low impact sound is required such as bedrooms.

Structure borne sound is where sound will travel through a structure from one level to another and this

may affect those living in high rise and low rise apartments. Building regulations generally try to reduce

this effect by introducing discontinuities in floor levels to break the sound pathway and an example of

this a floating floor which uses sound resilient pads or layers such as rubber underlay to isolate the floor

surface from the structure. Finally reverberated sound affects some building – this is where sound is

literally bounces off one surface onto another. Where there are lots of hard surfaces reverberation can

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be an issue and the best way of reducing reverberation is to introduce soft furnishings such as carpets,

curtains and furniture to deaden or absorb the sound.

Table 1.4 The three different types of sound

Three types of sound

1. Air borne 2. Impact 3. Structure borne

(source authors)

So what can you do when sound or noise is a problem in your new home? First of all identify the

source of the noise is it something you can change easily – for example some appliances such as

washing machines can be very noisy. Does the noise come from the machine itself or how it vibrates on

the floor (impact sound) or is it the structure borne sounds from the vibrations? It might be possible to

change its’ location, to dampen the sound by introducing side panels or to enclose it. Vibration noise

might be reduced by placing the machine on an insulating raft to absorb the vibrations or ultimately the

machine could be replaced with a quieter model. The most common noise in housing is the

transmission of noise form one floor to another or through the walls of one room to an adjoining one.

The best way of dealing with floor to floor sound is to lay a new floor on top of a sound resilient

underlay but make sure the new floor does not touch the walls or skirting of the old floor. Finally a soft

floor covering can be laid over.

Room to room sound transmission can be reduced by adding another layer of plasterboard to the

partition wall fixed with an acoustic sound sealant to help dampen the sound. Alternatively fixed

shelving or cupboards could be built on the wall to dampen sound. In townhouses or units you may

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experience problems with sound transmission you’re your neighbour and this can be difficult to deal

with. So what you can do is, check there are no cracks or gaps and, if so, fill them. Secondly add a

layer of plasterboard and or consider positioning shelving or cupboards along the wall if possible.

Finally it is always worth speaking to your neighbour in a non confrontational friendly way – they may

not realize the amount of sounds that is being transmitted.

Finally there is sound from external sources and this is the most challenging to deal with as you have

the least control over the source! See figure 1.1 for two examples.

Figure 1. 1. Unwanted sounds from external sources.

Traffic Airplanes

Secondary glazing, which is a second layer of glass around 150 to 200mm distance from the primary

glazing, is the most effective way of dealing with this type of noise – say from a motorway or an airport

but is quite expensive. Again sealing gaps and cracks will help and is a low cost option. Of course this

issue needs to be considered alongside the ventilation of the house because there an obvious conflict

between wanting fresh air inside and keeping unwanted noise out of your home. The provision of hard

and soft sound barriers (boundary walls) has limited effect on reducing sound but usually adds to

privacy which can be another issue for properties located on busy roads and so on. In terms of value add

– clearly living near to a busy road or airport is going to have a negative impact on home value – you

can offset this by taking steps, to suit your pocket, to reduce the problem. Make sure your real estate

agent is fully aware of the steps you have taken to address the problem.

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What about adapting your home to life changes such as increased or reduced family size?

Clearly as time goes by our housing needs change – it seems that at one moment there you need more

space and the next minute you have too much! Flexibility and adaptability are great features in a

property and clearly add to its value and its sustainability. The more flexible and adaptable a property

is, the longer life cycle it will have. This is because the property will appeal to a greater range of buyers

and it will suit their needs for longer periods of time. For example rooms that are well located in a

property so that they can be used as either bedrooms, or studies, or family rooms or home entertainment

rooms are very flexible and adaptable for users. Similarly properties which can be extended either

upwards or at ground level will also be able to accommodate changing requirements. In this respect

units and apartments often offer less flexibility and adaptability than other housing types simply

because they typically have fewer rooms to start with. It has to be said newer houses especially in inner

city or urban locations are taking up almost the entire plot these days and therefore offer less flexibility

and adaptability for owner than older properties located on generous land plots and this fact may affect

their long term value growth potential somewhat.

Figure 1.2 Life cycles and different housing needs over time

Life cycles

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Key summary points

What about the short-term and the long-term?

This discussion has indicated some of the different measures you can adopt over a range of

sustainability issue and add value to your home. Where you enjoy the benefit of the measure, what ever

it is you are enjoying added value in your home through increased comfort though you may not initially

enjoy added value in a monetary sense as such. As time goes by more people will be aware of the

sustainability measures to look for in houses and will be attributing more value to houses that have

them.

The discussion started by noting that even new house do not have the best possible building standards

we can achieve because the building regulations not only represent as compromise level of building

standards but also because the introduction of changes to the legislation takes time and there is always a

time lag between best building practices and the building regulations. In the long term the standards will

increase but we need to act before then if we want to do something bout climate change and at the same

time add value to our homes.

Also this discussion has explored some of the ways that new homes might adapt to varying levels of

sustainability without sacrificing value and still work within a realistic budget. The discussion

examined what measures could be taken in terms of energy and consumptions and to improve the health

and well being of a new home. All of the measures were assessed in terms of sustainability impact;

costs and durability before examining the value add implications of the different measures.

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Buyers are generally willing to pay more than the costs of installations for sustainability measures

because of the perceived benefits they will enjoy but also because someone else has done the hard yards

in terms of research and installation of the measure. Finally the discussion has demonstrated the

importance of collecting evidence to demonstrate to real estate agents and buyers the cost benefits of the

measures you have taken to improve the sustainability of your new home.