Browse Forums Heating, Cooling & Insulation 1 Apr 10, 2013 7:01 am Hi, My limited understanding of how this works...With DG in a window, the gap needs to be small to prevent internal air currents reducing efficiency. ie. air is cooled from the outside and falls down creating a loop. In a skylight situation, the glass is horizontal and therefore the distance for the cool air to be able to fall is going to be *much* less. ie the size of the air gap. Does this make the size of the air gap less critical in this case ? I have an old skylight in a bedroom and am considering adding a sheet of perspex to create a double skin/glaze to keep some heat in. Would it be a problem to have say a 100mm gap ? Re: double glazing in a skylight 2Apr 10, 2013 7:42 am davem Hi, My limited understanding of how this works...With DG in a window, the gap needs to be small to prevent internal air currents reducing efficiency. ie. air is cooled from the outside and falls down creating a loop. In a skylight situation, the glass is horizontal and therefore the distance for the cool air to be able to fall is going to be *much* less. ie the size of the air gap. Does this make the size of the air gap less critical in this case ? I have an old skylight in a bedroom and am considering adding a sheet of perspex to create a double skin/glaze to keep some heat in. Would it be a problem to have say a 100mm gap ? The air movement is caused by eddy currents, these are small rotating loops of air, so vertical or horizontal is just the same, 12mm is ideal. Your solution will certainly make a difference, but you need to think about condensation inside. Ed "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 It might be a bit darker in the mornings but the light is still light, so you should be getting it. Similar to what you see from your western windows 3 19978 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 19225 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 7711 |