Solar tubes (sun pipes), how much light do they let out?

[Dreadnaught]

Has anyone got a solar tube or sun pipe, etc? 

 

At night when viewed from outside, how much light do they emit from a building? Is the dome a bright point of light or just has the faintest of glows? The reason I ask is that I have a restriction on light pollution but am considering a solar tube instead of a window or roof-light to bring light into a dark corner. 

 

Many thanks.

[PeterW]

Mirror film on the inside would work to stop that. 

[Dreadnaught]

3 minutes ago, PeterW said:

Mirror film on the inside would work to stop that. 

 

Good idea. I thought of it too. Ever come across such an installation in practice ? I assume the film would reduce the amount of light coming in somewhat.

[ProDave]

They work very well to let light IN.  When viewed from outside at night they are just a faint glow so I don't think you will have a problem. 

[MrMagic]

I believe I have seen one with an integral blind.

 

Lovely, super simple bit of kit tho... fitted one on my previous house where we had an internal bathroom with no windows. Was amazing on a clear night how much moon light you got in the room.

 

Hope you manage to get it fitted.

[Nickfromwales]

Based on the ratio of what's available outside and what's available inside, in terms of transfer, I doubt there would be enough upward emitted light to 'pollute' . 

[lizzie]

 

 

@Dreadnaught I cant say I have ever noticed any light showing from our 3 but will check tomorrow its a bit late to go out and look now.

[lizzie]

@Dreadnaught Ian checked on his way in this evening and reports that a glow can be seen coming from the glass domes.  It is a dim glow but quite visible probably more so in our location where we have little to disturb the dark skies. Probably more muted in an urban environment with more lighting around.

[Dreadnaught]

Original poster here.

 

Thanks for all your replies, especially @lizzie's above! Armed with your all your advice I successfully negotiated for the light tubes that I am planning to be permitted in the design .