Thu, 16 Apr 2026 19:34:55 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31255#Comment_31255 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31255#Comment_31255 Wed, 27 Aug 2008 21:38:48 +0100 j40 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31257#Comment_31257 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31257#Comment_31257 Wed, 27 Aug 2008 21:57:15 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31258#Comment_31258 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31258#Comment_31258 Wed, 27 Aug 2008 22:12:55 +0100 j40 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31263#Comment_31263 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31263#Comment_31263 Wed, 27 Aug 2008 23:30:21 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31271#Comment_31271 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31271#Comment_31271 Thu, 28 Aug 2008 04:37:25 +0100 j40 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31474#Comment_31474 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31474#Comment_31474 Sun, 31 Aug 2008 06:58:44 +0100 RBT https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31479#Comment_31479 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31479#Comment_31479 Sun, 31 Aug 2008 12:45:39 +0100 mike7 Posted By: tonyNormal roof window with a light well or even a normal window. Borrowed lights can work as effectively as a solar tube too.
Pardon my ignorance, but aren't solar tubes just a versatile - and expensive - way of having mirrored sides to a light well? In a straightforward situation such as Tony suggests above wouldn't lining all or most of the sides of the well with ordinary mirror glass work just as well?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31485#Comment_31485 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31485#Comment_31485 Sun, 31 Aug 2008 15:08:44 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31507#Comment_31507 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31507#Comment_31507 Sun, 31 Aug 2008 23:36:40 +0100 j40
The other factor regarding the Solatube specifically is that the done on the top has some special way of getting light that comes in at an angle to be thrown down the tube.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31603#Comment_31603 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31603#Comment_31603 Mon, 01 Sep 2008 22:48:45 +0100 mike7 Posted By: j40
The other factor regarding the Solatube specifically is that the done on the top has some special way of getting light that comes in at an angle to be thrown down the tube.

If true, that would be really interesting. Is it true?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31624#Comment_31624 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31624#Comment_31624 Tue, 02 Sep 2008 11:29:49 +0100 j40
"Raybender® 3000 Technology Fresnel lens in the roof dome ensures that low level daylight doesn't just pass through the dome - it is redirected down the tube aperture at a steep angle to ensure fewer bounces and thus minimum light loss"

I found this at http://www.lightupmyroom.co.uk/Solatube_components.htm]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31674#Comment_31674 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31674#Comment_31674 Tue, 02 Sep 2008 21:07:21 +0100 mike7 Buyer's remorse is an emotional condition whereby a person feels remorse or regret after a purchase. It is frequently associated with the purchase of higher value items which could be considered "bad" although it may also stem from a sense of not wishing to be "wrong". So you could be wrong twice! Aaargh! A familiar feeling.....]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31684#Comment_31684 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31684#Comment_31684 Tue, 02 Sep 2008 21:34:19 +0100 j40
The definition I was alluding to would be a "doubt that surfaces when a buyer becomes aware that an alternative product may offer more desirable benefits than the one purchased, the buyer wonders whether the right choice has been made, sometimes known as "buyers remorse"". The competitor sun tubes have their own USP's - I was keen to hear from people with other systems installed or had done their own research. Heck- i'm not taking them out now!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31686#Comment_31686 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31686#Comment_31686 Tue, 02 Sep 2008 22:10:07 +0100 mike7 Posted By: j40I have seen a lazer pen directed at the dome and not pass through- instead thrown downwards- so from eye witnessing- yes it does work.
>

No doubt that is true for some directions of the pen light - but what about other directions? My suspicions are increased by the fact that solartube only mention 'EDCS' ie effective daylight collecting surface, (a parameter I've not heard of before but which perhaps suits their case) and it just so happens that the areas they quote have just about the same area as a hemisphere of the pipe diameter. The ratio is 2pi.rsq/pi.rsq which equals 2. http://www.solatube.com/en/brightenup.htm

It looks like you're intended to think this means it'll collect twice the light. It won't. If it did, they'd say so.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31689#Comment_31689 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31689#Comment_31689 Tue, 02 Sep 2008 23:19:20 +0100 Terry
I would tend to agree with Tony regarding light wells, but they are not practical when needing to get light downstairs. Granted light tubes lose efficiency with increase in length, but if it is the only way.....
Will report back on effectiveness once ours are fitted.

Regarding installation - it is quite feasable with DIY skills or a competant general builder. Instructions supplied so no specialist skils required.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31712#Comment_31712 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31712#Comment_31712 Wed, 03 Sep 2008 09:31:31 +0100 j40 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31869#Comment_31869 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31869#Comment_31869 Thu, 04 Sep 2008 19:59:58 +0100 arthur
Since windows are inevitably weak points in a well insulated building unless solar gain can be stored (at least overnight but preferably interseasonally) the question is should they be there at all and especially in the roof since heat rises. Natural light is perhaps an unjustifiable luxury. Energy saved in electric lighting may not compensate.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31870#Comment_31870 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31870#Comment_31870 Thu, 04 Sep 2008 20:07:21 +0100 Rachel https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31888#Comment_31888 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31888#Comment_31888 Thu, 04 Sep 2008 23:31:42 +0100 j40 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31904#Comment_31904 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=31904#Comment_31904 Fri, 05 Sep 2008 11:14:30 +0100 Rachel https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32025#Comment_32025 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32025#Comment_32025 Sat, 06 Sep 2008 21:23:04 +0100 j40 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32028#Comment_32028 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32028#Comment_32028 Sat, 06 Sep 2008 22:47:04 +0100 Rachel https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32035#Comment_32035 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32035#Comment_32035 Sun, 07 Sep 2008 07:38:13 +0100 joe.e Posted By: arthurSince windows are inevitably weak points in a well insulated building unless solar gain can be stored (at least overnight but preferably interseasonally) the question is should they be there at all and especially in the roof since heat rises. Natural light is perhaps an unjustifiable luxury. Energy saved in electric lighting may not compensate.
That sounds a bit spurious. Plenty of houses have been built that don't need any heating, but which have plenty of natural light. Besides, if the loss of heat at night was a problem, you could always fit an insulated shutter under the light-tube, hinged to one side and with a catch to hold it back against the ceiling when open. I'm actually planning something like that for the windows in a structure I'm hoping to build.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32043#Comment_32043 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32043#Comment_32043 Sun, 07 Sep 2008 10:09:55 +0100 arthur
I agree about shutters. I'm surprised people don't use them more and that they're not more available. I suppose they take up space. However, without a heating system the space taken by all those radiators under windows could be occupied by a hinged or sliding insulated shutter. You'd think an enterprising window manufacturer would develop them but I've never seen anything very satisfactory.

For a sunpipe though it should be easy enough for a small opening to add a shutter.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32045#Comment_32045 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2446&Focus=32045#Comment_32045 Sun, 07 Sep 2008 10:38:03 +0100 joe.e Posted By: arthurDo many passive buildings of roof windows? Don't they tend to arrange windows carefully on the south side and minimise them on other surfaces?
I don't know, to be honest; I was just responding to the idea that natural light is an unaffordable luxury. But in designing a passive house, it would surely be helpful to make the overall form of the building as compact as possible, approaching cubic as opposed to a long, flat rectangle; this might mean that some of the interior spaces would lack sufficient natural light. In that situation I would have thought that the combined gains from non-use of electric light and heat conservation through building form would make a rooflight worthwhile.]]>