New Prevention of Fall Requirements for Australian windows

In response to small children falling from windows, the Australian Building Codes Board (ABCB) undertook to introduce new measures through the Building Code of Australia 2013.  The requirements come into effect for Development Approvals after 1 May 2013 and will be managed by Certifiers.  This blog will focus on residential homes.

The requirements only affect bedrooms that are two storeys or above or on steeply sloping blocks.  The important factors are the size and height above the floor of the opening and if there are footholds that could be used for children to climb up.

If the window opening is within 1700 mm of the floor then the following applies:

• if the opening is more that 865mm above the floor and there are no climable elements then removable screens or restrictors that can be overridden by an adult may be used.
• If the opening is less than 865mm above the floor or there are climable elements then permanent screens or restrictors are required.

There are a number of hardware solutions available such as short chain winders or barrier screens which will allow window to comply.  A solution mush not permit a 125mm sphere to pass through it and not have any climbable elements between 150mm and 760 mm above the floor to facilitate a child climbing.

One question that has arisen is how do these requirements affect the BCA Ventilation requirement that the opening area of a window be 5% of the floor area of the room?  The ABCB advised that the ventilation area of a window is calculated on the total area of the sash ad not the openable area....

In summary, for windows in bedrooms where the fall height is 2m or greater:

• If there is no opening within 1700 mm of the floor then no restrictions apply
• If the opening is within 1700 mm above the floor and there is a climbable element between 150mm and 750mm above the floor then opening much be permanently restricted to 125mm or fitted with a non-removable robust screen
• If the opening is between 865 and 1700 mm above the floor (no climbable element between 150mm and 760 mm) then the opening must be restricted to 125mm or fitted with a removable robust screen
• If the opening is withing 865 mm of the floor (climable element between 150mm and 760mm above the floor) then the opening must be permanently restricted to 125mm or fitted with a non-removable robust screen.

Information source:  AWA Prevention of Falls from Windows Key Message.  www.awa.org.au.

What considerations should be made on windows and doors in Canberra?

Climate Zone for Canberra

Canberra is considered to be a heating climate and we are in Zone 7, this means that we want to get the maximum sun that we can into our homes in winter and the least in summer.  Because Canberra gets so cold, we tend to run the heater while we are in the home.  Once we get the beautiful sun into our homes, we want to keep it there.  There are a several ways that you can do this:

• Replace your windows and doors with double glazed unit
• Install heavy drapes and pelmets (not much view after
• Install a second window next to the other one
• Install a piece of Perspex over the frame to create a cavity

If you are replacing your windows and doors then you want to make sure that you are getting the best bang for your dollar.  You will want a low uValue (insulation factor) – the lower the better.  The uValue measures how easily a window conducts heat, how much heat loss you will have and how well the window or door is insulated.  The measure should be overall window and frame and includes seals and spacers.

These are the common uValues for the main window choices:

Standard single glazed aluminium 4mm – 5.9

Standard double glazed aluminium 3mm/12mm air/3mm – 3.5

Thermally broken double glazed aluminium  - 2.5

Timber double glazed 4mm/16air/4mm – 2.4

uPVC double glazed 4mm/16 air/4mmea – 1.8

It is interesting to note that the uValue has the potential to improve up to approximately 0.3 stars for each unit reduction in uValue.  Each star corresponds to reduction in heating and cooling requirements by approximately 20% to 30%.  You will save approximately 10.000 to 15.000 MJ of energy per star which will save your heating bills of about $300 a year (source:  wers.net).

The frame plays a large role in getting the uValues right.   

Aluminium leaks heat and cold while timber needs to be maintained each year so that it stays in good condition.  uPVC is an insulated frame that doesn’t leak heat or cold and doesn’t need maintenance.

The other side of the coin is Solar Heat Gain Co-efficient (SHGC)

SHGC measures how much solar energy gets through the windows and doors.  It is a number between 0 and 1. The lower the SHGC is, the less heat that it transmits.

The SHGC will be relevant to different elevations in Canberra.  I would recommend a high SHGC on the north side provided there is an eave or shading in place for summer.  You want to get as much sun through the glass that you can in winter.  East and West would have a low SHGC and south won’t see any sun so you want to make sure that the uValue is very low.

SHGC can be reduced by applying selective low E (low emissivity) coating to glazing.  It can reduce heat loss in winter as well as solar gain in summer.

Glazing Calculator

If you are building a new home or extending an old one, a glazing calculator will need to be submitted to your Certifier and both the uValue and the SHGC will be required.  The figures are entered into the calculator on each orientation of the home along with shading and a green tick or a red tick will appear in the spreadsheet.  If you get a green tick you are home and hosed, if you get a red tick you need to change your windows/door or glazing.

Solace Creations at 17 Townsville Street Fyshwick and will be able to help you with these considerations and is available on 02 6260 1621.  www.solacecreations.com.au

Window Testing in Australia

 Window Energy Rating System

The Window Energy Rating System was established in 1995 to give ratings and standards to windows and doors in Australia. 

Windows and doors sold in Australia have to be tested to our harsh climate.  Ratings can be found on Wers.net under residential certified products.  Below is a sample of Inframe Glazing Systems Ratings.

There are three ways that windows and doors are tested:  testing at an independent facility (the best), computer simulated (next best) and using overseas or other manufacturers ratings.  It is clear on the ratings what has been used to test the windows.  Those that use other's ratings have it noted as generic on the title.  Those that have computer simulated often have an air infiltration rating of 0.5.

What do the ratings mean?

Uw is the rate of heat loss of a window assembly.  The lower the uValue the better its insulating properties.  The best rating is using the whole window.  Ratings range from 2.0 to 10.0.  Uw is the whole window, UC centre of glass and UF is frame.
 
SHGC – how well a product blocks the heat caused by sunlight. The fraction of incident solar radiation admitted through a window, both directly and absorbed and released inward.  Between 0 and 1.  Lower the rating the less solar heat gain. 

VT – how much light comes in through the window. between 0 and 1 – the higher the rating the more light comes through


Air infiltration (leakage) on a test report. The lower the air infiltration figure the less air will pass through cracks in the window or door assembly.

 

How is the testing done?

  AS 2047 performance test is undertaken at an independent facility

It is the mandatory minimum specification for windows and doors used in Australia it includes compliance to the Glass Standard AS 1288. 
 
The following performance tests are undertaken to verify product performance claims.
 
AS 4420.2 Deflection Test - positive and negative wind pressures are applied to the face of the window to test the maximum deflection under wind load.
AS 4420.3 Operating Force Test - to verify that an opening sash is capable of opening and closing without undue effort.
AS 4420.4 Air Infiltration Test - the air leakage of a window is tested to ensure energy and acoustic efficiency.
AS 4420.5 Water Penetration Resistance Test - this test is designed to ensure no water leaks through the window into the building.
AS 4420.6 Ultimate Strength Test - negative and positive wind pressures are applied to the window to at least 1.5 times the design wind pressure to ensure it does not fail in unusual wind conditions.

 

 

Before you buy any window or door, ask the supplier to see evidence of these tests.  This will give you an assurance that you are buying windows and doors suitable for our climate.

 

 Information from wers.net, awa.org.au

Karen Porter is now a Board Member of the Australian Window Association

Karen Porter, Managing Director of Solace Creations has served as a Board Member of the Australian Window Association (AWA).  Karen will represented suppliers on the east coast of Australia for a 2 year period.

Karen was an integral part of the AWA and provided a greater focus on energy efficient windows and doors so that they become a standard feature of new construction.

Karen ensured that the Canberra Community was well represented at the meetings along with uPVC and double glazing.

Building a Better Home in Canberra

How to get started - the Block

Building a home from the very early planning stage provides you with the best opportunity to live in a home that saves you money in heating and cooling, has awesome comfort levels and reduces your impact on the environment.

Where you chose to build your home will have an impact of how much you can achieve with smart planning.  The block is very important and ideally should allow you to place most of your living areas facing north.  Many of Canberra's blocks are not subdivided in a way that you can always achieve this aim.  If you get first dibs on a block, make sure you can make the most of the north.

Your budget will play a large role in what you can afford and you will need to be creative in your planning to ensure that you can achieve the desired home within your budget.

Orientation of your home is the most important step to utilising the sun's energy and the block will either help or hinder your success.

When selecting your block you should consider:

• is it well oriented? rectangular blocks with the long side facing north let you get more use of the "free" sun.  Ideally the long side of the house (with windows to the main living areas) face between 5 degrees east of the compass north and 30 degrees west of north.
• do you really need a massive home?  Consider a size suited to your family without the traditional formal lounge and dining that most people don't use.  Tailor the house to your expected family size.  You will use less energy to heat and cool the home;
• go to the block at various times of the day and see what shading comes across the block from neighbouring homes and trees.  This will need to be factored into your planning;
• does the block slope?  Can you maximise the block and build within the ACTPLA restrictions? Are there easements that need to be kept clear?
• what is the outdoor space like?  how does the family live now? Do they use the yard a lot?
• Is it possible to build an extension on later when your family grows?
• Will you get the required privacy from your neighbours and the street?

If you are able to focus on this part of the process then the rest of the process will flow nicely.  An energy efficient home does not have to blow your budget, the trick is to plan it properly and go in with your eyes open and do your research.

The next blog will focus on the right home for energy efficiency.

Come and see us at our Super Showroom at 17 Townsville Street FYSHWICK or www.solacecreations.com.au

Bibliography: 

Selecting a greener, better house with lower running costs and saving the environment 2008

ACTPLA Guide to Good Design 2004

Energy Efficient Windows in Canberra

Windows have traditionally been treated as just any another building material.  They are sourced as cheaply as possible and the same traditional style is put into the design and the build.  What a lot of builders, architects and home owners don't take into account is that they provide a massive opportunity to improve the insulation of the home.  

They provide light into the home along with fresh air but they also provide the opportunity to save heat loss in winter and heat gain in summer.  The frames play just an important part of the insulation process as the glass.  These are the best frame materials for energy efficient homes:

1. uPVC frames
2. Timber frames
3. Thermally broken aluminium frames

Combine the insulated frames with double glazed units and you will experience comfort, cheaper energy bills and still have light coming into your home.

Australia has a wide range of Climate Classes.  Canberra is a heating climate and is in Zone 7.  In Canberra we want to draw the sun into our home and then trap it there to benefit from free solar heating.  In summer we want to keep the heat out but be able to open our windows to benefit from the air flow.

In Canberra we want our windows to have a low U-value and high solar heat gain coefficient (SHGC) (see below).  It is important to ensure that each window and elevation (N,S,E and W) are considered to ensure they let the sun in during winter and keep the sun out during summer.  www.wers.net show the ratings of all rated windows and you should consider these when selecting your windows and doors.  Solace Creations provides a wonderful advisory service on new plans and existing homes to help you to select the best windows for your home www.solacecreations.com.au.

When you are building a new home or extending an existing home, ACT Government requires that a glazing calculator is completed or an energy audit to make sure that the required star rating is achieved.  The U-value and SHGC are important factors for the calculations and can be found on www.wers.net or from your window supplier.

What is a U-value

Wall insulation such as batts have an R-value rating.  This best batts for insulation is as high a rating as possible.  Windows and doors have U-values and for Canberra you want a low rating.  The U-value is a measurement on how well the windows and doors prevent heat from escaping.  Ratings can be from 2.0 to 10.  This should include the frame, glass, seals and spacers.  If a window such as ours has a U-value of 1.8, that means that 1.8 watts per metre is lost per hour.  Some aluminium windows are rated at 5.8. This shows that those windows lose heat much quicker than those with a lower U-value.  You can double glaze standard aluminium but the frame will still leak a lot of your heat.

What is Solar Heat Gain Co-efficent (SHGC)?

SHGC is a measure on how well the windows and doors block heat caused by sunlight.  This measure is a combination of how much sun is directly transmitted towards the window, absorbed by the window and ultimately released inwardly.  The SHGC is a number between 0 and 1.  The lower the number, the less heat it transmits.  The low ratings are excellent for the west side, however, you need to remember that if you have a low SHGC in summer, it will also be a low SHGC in winter meaning that you won't get as much of that lovely afternoon sun through your windows and doors in winter.  You can't beat natural shading from a tree or an awning for the summer westerly sun.

Orientation

Nothing beats perfect orientation and more aspects of energy efficient homes will be discussed in further blogs.  If you orient your home correctly, seal up the whole building envelope with insulation (including windows and doors) then you will not have to rely on heating or airconditioning.  This will save you $$$ on your bills and you are contributing to our planet.

Picture source:  www.wers.net

17 Townsville Street Fyshwick www.solacecreations.com.au

Insulation Ratings of your Windows and Doors

Window Energy Rating System (WERS)

WERS was established in 1995. WERS provides ratings and labels for windows and doors just like your fridge or washing machine is labelled.  The ratings show their annual energy impact on the home in any Australian climate.  They show how well the heat is kept in your home and how much sun gets through the windows and doors.  The give you guidance on particular sides of your home and how to maximise and minimise the sun and your insulation.

To get a rating, window manufacturers must have their windows and doors tested through an independent accredited rating organisation and the Australian tests are very stringent compared to the USA, Europe or the UK. 

It is important that the windows and doors that you are purchasing have been rated for the Australian climate.  There are many companies selling imported windows and doors that have not been tested for this harsh climate.  You are making a large investment, please make sure that the investment is sound and based on testing.  We have seen white windows go yellow very quickly as they were not UV stabilised.  Ask the company you are buying from for their test results or ratings.

WERS is independent and is a fair, rigorous and credible systems for testing performance claims.  All WERS rated windows meet or exceed the relevant Australian Standard. Members of WERS participate in an annual audit to ensure that quality control is maintained.  WERS members can be found on www.wers.net/Certified-Products-Residential.

The home owner benefits from WERS ratings as the amount of stars adds to an increased home resale value, provides a comfortable home and assurance that they are the right ratings for your elevations and rooms.

If you want assurance of your purchase, don't risk your investment by dealing with a supplier that hasn't had their products tested.  All of Solace Creations' windows and doors have been tested by WERS and you can be guaranteed by their performance and quality.

Information obtained from www.wers.net.

What is Double Glazing?

Double glazed units are also known as Insulated Glass Units (IGU).  They are just as important to your home as the batts in your walls and ceiling.  They mainly insulate your home against heat loss and with a change to the glass makeup can reduce heat coming into your home.

Standard double glazing will not stop the sun coming in during winter.  This is one of the most commonly asked questions from our clients.  You need the sun to come into your home so that you can benefit from the free heating. Double glazing lets it in and then traps it in the home.

The important component of an IGU is the airgap between the two glass panes.  The gap is filled with either air or an inert gas which is a much poorer conductor of heat than the glass. This means that less heat will escape through an IGU than a single glazed window.  Think of IGUs in the same way that you think of wall insulating batts.  The air trapped between the two panes of glass forms an insulating layer between your home and the cold outdoors.

Insulated Glass Units can also be triple glazed, however, this is not as popular in Australia as it is in Europe.  The drawing below is a simple explanation of a double glazed unit:

Drawing Source:  Wikipedia

1, 2, 3, 4 - Glass pieces in the unit

There are two pieces of glass in the unit with four sides and the sides of the glass units are named to avoid confusion when making the glass.

Surface 1 is on the outside pane and faces the outside
Surface 2 is on the outside pane and faces inside
Surface 3 is on the inside pane and faces outside
Surface 4 is on the inside pane and faces inside 

5 - The Window Frame

This is the window frame and this topic will be a separate post.  The frame can be aluminium, timber, uPVC, fibreglass or a composite.

6 - The Spacer Bar

Double glazed units are put together in the glass factory, they are not assembled at the building site or home. The two pieces of glass are held together with an aluminium or insulated spacer bar that seals the space and keeps the glass in place.  The bar goes between the two pieces of glass and is of various widths.  The optimal spacer bar for effective insulation is between 10mm and 20mm.  The bar has desiccants inside to prevent humidity and condensation between the two panes of glass.

The double glazed unit can be made up of various components to keep the heat out, keep noise out or in and increase security.  This will be a separate post as there is a lot of information to consider.

The sides of the glass units are named to ensure they are made up correctly.

Surface 1 is on the outside pane and faces the outside
Surface 2 is on the outside pane and faces inside
Surface 3 is on the inside pane and faces outside
Surface 4 is on the inside pane and faces inside 

7 - Seals

The seals are attached to the frame and press up against the glass unit to stop airflow.

8 - Timber Reveal

This is also known as your window sill. 

9 - External Sill

This is the external window sill.

Air versus Argon Gas

Most double glazed units are air filled, however, it is becoming more common place to inject an inert gas like argon.  Argon is injected into the double glazed unit in the factory and sealed to prevent leakage.  Argon gas is an even poorer conductor of heat and conducts about 33% less heat than air.  There is some research to suggests that gas leaks over the years, however, it is at a very slow rate if any.  The price of argon has reduced and it is now very affordable.  Some companies provide the argon fill as a standard feature.

Summary

In summary, double glazed units are just as important as wall, ceiling and floor insulation.  They trap air between the two panes of glass and this is the insulation.  They let the lovely warm sun in and then they trap it inside.  It is important that you always use sealed double glazed units as they stop condensation and provide a better insulation rating.  Some people retrofit by placing another piece of glass into the window and this is not as effective as the sealed units.

The spacer bar is important.  You want to make sure it is between 10mm and 20mm. If they are too close together heat can easily transfer from one side of the window to the other which provides less insulation (just like the thickness of your batts).  If they are too far apart then the air can move inside the two panes which provides less of an insulator.

Karen

17 Townsville Street Fyshwick

www.solacecreations.com.au

2015 - Year of Double Glazing

I am often blown away by the fact that here in Canberra, we are still using single glazed aluminium windows and doors as standard inclusions.  One of the coldest climates in Canberra and we don't insulate our windows and doors. Yet we do insulate the walls right next to the openings.  Why do we do that I wonder?  Oh that's right we can shut our heavy drapes and put pelmets on every window.  We all like to live in a cave don't we?  Well for the price of heavy drapes and pelmets we can have lovely insulated windows and doors with double glazing.

There are a lot of ways that you can have a comfortable home and I am going to be doing a series of blogs that will give ideas and inspiration to new home owners and existing home owners.

It is about time, residents of Canberra, that we looked outside the square of how we always built homes and be a little bit innovative.  The outcome will be a comfy home that is cheap to run.  Stay tuned for the next blog.

In the meantime, if you pop into our shop at 17 Townsville Street Fyshwick, our friendly staff will give you on the spot inspiration.