Browse Forums Heating, Cooling & Insulation 1 Mar 21, 2023 1:09 pm Hi all, we are building currently and again we are asked to pay an additional ~$8500 for an upgrade by using lightbridge low e glazing to all windows and doors in order to achieve the 6-star building requirement in Victoria We already have sealed double glazed panels to all windows and external doors included as part of the specification from the builder. I’m just wondering if this is reasonable cost at all and do we have any other options? I’m just surprised that even with this upgrade we still couldn’t achieve 7-star building (it says 6.8 star if there’s such a thing) so I am not even sure if we are doing this right FYI what’s included as insulation is as below R4.0 Glasswool batts to the roof ceiling spaces. R1.5 ‘Vapa–Chek’ building blanket under steel roofing material. R2.5 Acoustic/Thermal Glasswool batts to all external walls. Reflective foil wall wrap (solid or breather) to all external walls. R2.5 Glasswool batts to any floor space that cantilevers over the outside of building or that sits over the garage. R1.7 Structural Foam UnderSlab Insulation Are we doing it right ? Re: Lightbridge “low E” glazing as an upgrade 2Mar 21, 2023 1:51 pm Ostrich36 Hi all, we are building currently and again we are asked to pay an additional ~$8500 for an upgrade by using lightbridge low e glazing to all windows and doors in order to achieve the 6-star building requirement in Victoria We already have sealed double glazed panels to all windows and external doors included as part of the specification from the builder. I’m just wondering if this is reasonable cost at all and do we have any other options? I’m just surprised that even with this upgrade we still couldn’t achieve 7-star building (it says 6.8 star if there’s such a thing) so I am not even sure if we are doing this right FYI what’s included as insulation is as below R4.0 Glasswool batts to the roof ceiling spaces. R1.5 ‘Vapa–Chek’ building blanket under steel roofing material. R2.5 Acoustic/Thermal Glasswool batts to all external walls. Reflective foil wall wrap (solid or breather) to all external walls. R2.5 Glasswool batts to any floor space that cantilevers over the outside of building or that sits over the garage. R1.7 Structural Foam UnderSlab Insulation Are we doing it right ? have you seen the energy report yourself, and checked whether it's been completed using correct inputs? this factsheet might be handy too: https://www.nathers.gov.au/sites/defaul ... 0stars.pdf maybe chuck some fans in instead? surely would be cheaper. also you might not need to upgrade all windows, just some that cause the biggest rating decrease. Re: Lightbridge “low E” glazing as an upgrade 3Mar 21, 2023 2:35 pm I have recently came across LandVac windows and glazing https://www.bmsydney.com.au/bm-landvac/ They perform better than most of the walls (to U values of 0.4) and cost quoted with thermal broken frames was around $560 per sqm. I am quite sure with those you will be able to hit even 8 stars Re: Lightbridge “low E” glazing as an upgrade 4Mar 24, 2023 11:14 am What are the u-values of your double glazed windows? There can be very poor double glazed windows. You should be aiming for a u value at least under 3 (ideally around 2). I'd upgrade ceiling insulation to R5 or R6. The real problems might be with your design anyway. If it's not too late, you can hire an energy assessor to model your plans and run through why your rating is so poor. They can give you best bang for buck recommendations on how to improve. This is one of the reasons I decided to go overseas for my double glazed windows. As the builder indicated, he's worked on many upmarket builds, these were the most well… 13 19679 For your reference Performance Labels: Window assemblies in housing, except timber windows, must be labelled so the label can be seen when it is in situ. For timber… 6 10271 4 6340 |