We're looking to build a glass roofed extension/conservatory on the back of our house (7-8 metres long).
We want to use this room in winter and so are keen to make the roof and windows as warm as possible (without going for a solid roof).
We are considering a glass roof from PolySolar which has integrated PV and is reportedly affordable (waiting on final quote, but it is a different type of PV to normal and is cheaper although less efficient - 8% instead of normal 15-17% but much higher Watts/p).
The U-Value for this is quoted as 1.4, whereas a solid roof would be 0.2.
This thread suggests that 1.1 - 1.2 would be an acheivable value, but that once we're under 1.4, the bigger savings can be harnessed from better frames.
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3304
Is anyone aware of, or seen any "Secondary Triple Glazing" that could be applied in this case ? I'm thinking that I'm not worried about my head room, and single skin of Acrylic or Glass below the conservatory roof (but not in contact) should perhaps help this system approach a U-Value more like the Ultrafram Utopia (see my other thread).
(by secondary triple glaing I mean just a separate piece of glass or plastic inside, like what people used to use to convert old glass to double glazed - apparently the U-Values weren't so different to a sealed unit in the early days).
Not sure if that makes sense.
We want to use this room in winter and so are keen to make the roof and windows as warm as possible (without going for a solid roof).
We are considering a glass roof from PolySolar which has integrated PV and is reportedly affordable (waiting on final quote, but it is a different type of PV to normal and is cheaper although less efficient - 8% instead of normal 15-17% but much higher Watts/p).
The U-Value for this is quoted as 1.4, whereas a solid roof would be 0.2.
This thread suggests that 1.1 - 1.2 would be an acheivable value, but that once we're under 1.4, the bigger savings can be harnessed from better frames.
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3304
Is anyone aware of, or seen any "Secondary Triple Glazing" that could be applied in this case ? I'm thinking that I'm not worried about my head room, and single skin of Acrylic or Glass below the conservatory roof (but not in contact) should perhaps help this system approach a U-Value more like the Ultrafram Utopia (see my other thread).
(by secondary triple glaing I mean just a separate piece of glass or plastic inside, like what people used to use to convert old glass to double glazed - apparently the U-Values weren't so different to a sealed unit in the early days).
Not sure if that makes sense.
