Thermal Efficiency and Modern Glazing. Presented by James Whitehouse Specifications Manager Capral Aluminium

Transcription

1 Thermal Efficiency and Modern Glazing Presented by James Whitehouse Specifications Manager Capral Aluminium

2 Hot Topics - Windloads AS2047 states that it is the purchasers responsibility to nominate the design wind pressures IE the client not the Window Company Must be calculated by a qualified Structural Engineer Must include corners, building height & terrain considerations Values in kpa/pascals for both ULS & SLS to AS N/C rating to AS4055 for Class 1 and 10 buildings only.

3 Hot Topics - Thresholds AS4654 does not directly affect the framing selection but it s implementation can amend the opening you are installing into. Flush thresholds now require an external storm drain. Other full height glazing requires a hob detail with a height defined in a table in AS4654.

4 Hot Topics - Acoustics Historically the last issue addressed in the glazing package design but now becoming one of the first asked about. Older reports still just specify a glass & assume performance. The same glass in different frames will give wildly different values. Double glazing has negligible benefits unless acoustically designed. System Glass Rw 950 Sliding Window Sliding Window with Q-lon Seals Hinged Door Artisan Bifold & 900 Patio Slider Doors Fixed Frame Awning into 419 Frame Awning into 419 Frame Double Glazed 6.76/12/ Euro Tilt/Turn Window

5 Thermal Efficiency An Actual HOT Topic

6 Increased Stringency Government moving to increase energy efficiency requirements for non-residential buildings in 2019 NCC update with residential to follow in 2022 Result is increased requirements for double glazing, thermally broken and energy efficient systems in commercial façades Very likely to have a significant impact on residential systems depending on measures proposed

7 Glazing and Compliance The NCC Objective is to reduce greenhouse gas emissions by efficient use of energy Buildings are deemed as amongst the highest producers of greenhouse gases. Glazing compliance is assessed as part of the proposed building solution with deemed to satisfy provisions BCA Class 1 & 10 (Housing) are handled via Whole of House Energy Rating Systems BCA Class 2-9 Buildings are dealt via Section J calculations

8 WERS WERS (Window Energy Rating Scheme) publishes a list of Whole of Window energy ratings for frames & glass combined. The ratings are then used in both Energy Rating software & Section J calculators so have a Residential & Commercial section TOP TIP Acoustic requirements & WERS ratings often create a glass combination issue that isn t covered in architectural drawings and can lead to costly arguments later.

9 WERS Extract

10 WERS System Variations Changing the frame with the same glass differs the values Also true across similar frames from different suppliers.

11 Factors Affecting Performance Glazing Orientation Shading Type of Glass Single / Double Glazed Tinted / Low E Coatings Argon Filled Units Type of Framing Flushline or Centreglazed Thermally Broken

12 Example of Shading

13 Emerging Trends Prediction that soon all aluminium window suites will need to accommodate double glazing As awareness of double glazing and thermal efficiency increases, a modern, commercial look is in favour in mid-high end homes. This is leading to systems evolving swifter than ever before

14 Evolution of Systems From this Into this Then this And now into this

15 Thermally Broken Systems Outershell Thermal Break (also called Isolator) Inner Shell

16 Thermally Broken Systems HI Options Extra Insulation in chambers Increased thermal performance

17 Thermally Broken Systems Spandrels All in one units to offer increased thermal performance across the façade. U-values on spandrels can be as lower than 0.35

18 Emerging Trends Semi Frameless Doors Demand for large, semiframeless sliding doors in both commercial and residential applications Advanced Façade Systems Operable and multi-faceted structurally glazed curtain wall and façade systems

19 AWS 75 Deeper pocket systems will become more commonplace to carry thicker glass units Flush thresholds are a key feature along with AS4654 compliance via hob or stormdrain details

20 Thank You Any ASS 39 PD