IMO the light should not be capped as it would lessen the life of the driver in the fixture.
I reckon the best covers would be fairly tall(just past the insulation) and have a few little holes to help cool the driver heatsink down.
Browse Forums Building A New House Re: LED Downlights and normal lights 41Jun 13, 2012 11:50 pm IMO the light should not be capped as it would lessen the life of the driver in the fixture. I reckon the best covers would be fairly tall(just past the insulation) and have a few little holes to help cool the driver heatsink down. Building with Jandson Homes - Eclipse 18. http://adgnetworks.blogspot.com/ Re: LED Downlights and normal lights 42Jun 14, 2012 12:19 am How would one weigh-up the cost of the reduced life of the driver against the cost of the lost heat through the hole in the insulation? And do 240V GU10 LED fixtures get hot enough that they do themselves damage if there's nowhere for that heat to go? ie. are we totally sure it's not something that's more applicable to halogens & incandescents (eg. the 50W 12V MR16 globes I have here) than to LED's? *edit* Clearance & airflow recommendation question has now been fired-off to Philips Lighting product-support department regarding 240V LED downlights ... Re: LED Downlights and normal lights 43Jun 14, 2012 3:33 pm Some Crazy Person Clearance & airflow recommendation question has now been fired-off to Philips Lighting product-support department regarding 240V LED downlights ... Hrmmm. If anyone's at all interested in the response, Philips said: "Thank you for your email. We recommend you do not use these covers in your ceiling. They could affect the life of the lamp." So it seems you can either have downlights OR insulation, you can't have both. Re: LED Downlights and normal lights 44Jun 14, 2012 4:16 pm sim_mun if you follow this link at the bottom of the page there is an automatic LED calculator. IT calculates the pay of time for LED down lights. That doesn't seem to take into account the money you spend on the heat you lose by not being able to insulate near the LED - or am I reading it wrong? Re: LED Downlights and normal lights 45Jun 14, 2012 4:44 pm Forg We recommend you do not use these covers in your ceiling. They could affect the life of the lamp."[/i] So it seems you can either have downlights OR insulation, you can't have both. Did you show them your proposed paper based cover? Building with Jandson Homes - Eclipse 18. http://adgnetworks.blogspot.com/ Re: LED Downlights and normal lights 47Jun 14, 2012 6:49 pm CFL will not be available when LED come down in prices. but it is somewhat ridiculous claiming everyone should go directly with LED setup without even considering CFL as a long term / temporary solution. CFL light output is not bad that's all i can say. Re: LED Downlights and normal lights 48Jun 14, 2012 7:15 pm adgn Did you show them your proposed paper based cover? The specific statement was "they could affect the life of the lamp"; I don't think they cared if the cover was made out of carbon-fibre ... Putting aside the fact that no cover would be acceptable, your inference is that being rated to 1000°C (including being in contact with the thing that's 1000°C - even though LED's get to ~60°C if I'm reading correctly?) doesn't mean anything. I think this is leading nowhere for my purposes, but what else is out there that's better & what's wrong with the stuff I referred-to? Re: LED Downlights and normal lights 49Jun 14, 2012 8:28 pm urgent query - we just had insulation installed today. Despite me telling DH about the downlights and insulation issue, it had somehow slipped his mind so our insulation had 200x200 open squares around the down lights (which we learnt tonight is a legal requirement so prevent fire). There are cover / caps (which I think forg was mentioning). But just wondering - what have others with downlights done with their ceiling insulation? With gaps that wide it completely reduces the effectiveness of insulation... SunshineT's Build: viewtopic.php?f=31&t=34585 Designs start: 4/12/09 DA: 5/7/11 Demo: 22/12/11 Slab: 24/2/12 Keys: 31/8/12 Re: LED Downlights and normal lights 50Jun 14, 2012 8:45 pm Hey T, you want to be careful, not all downlights are allowed to have a cap on them, and they can seriously affect the lifespan. The ATA do sell them in their shop if you want to check them out. Our gaps are only going to be about 90mil around the light and we only have 8 in the house. Re: LED Downlights and normal lights 51Jun 15, 2012 12:01 pm I've read quite a lot that excess heat can seriously effect LED life-span so don't be mistaken thinking because they "feel cool" compared to halogens heat is not an issue. That's why the more expensive ones have decent size heat sinks. Also you should take the claimed huge life-spans of LED's with a very big grain of salt. I've seen numerous reports of them failing within a year, especially the cheaper ones. I'm afraid at current prices quality LED's don't make any sense- spending $70-80+ on a light which takes 10+ years to payback the energy savings is a false economy especially when you can expect some/all to fail before that time despite advertised claims. In my mind prices for quality LED's needs to get to around $30 or less to make sense. Unfortunately there is no clear alternative- CFL produce rubbish light output and halogens are on the way out. I'm about to start building and my hope is LED's continue to drop in price by the time I'm ready to install to a price point that makes sense. Of course as others have suggested you lose ceiling insulation performance with downlights. To be honest if your concerns are purely efficiency, cost savings and light performance you would avoid downlights all together and just choose standard ceiling fixtures, but of course aesthetics is usually the driving factor. Build Thread: viewtopic.php?f=31&t=57639 Re: LED Downlights and normal lights 52Jun 15, 2012 6:57 pm greenfish Our gaps are only going to be about 90mil around the light and we only have 8 in the house. Hey Greenfish, I'm awaiting confirmation but it seems that even if your using LED lighting you still have to comply with AS3000 wiring rules which state a 200mm clearance to any structural member or insulation. This is because standards australia is yet to make a ruling on LED. I will let you all know once it's confirmed. Still Waiting for Titles!!!! Re: LED Downlights and normal lights 53Jun 16, 2012 7:43 pm Forg sim_mun if you follow this link at the bottom of the page there is an automatic LED calculator. IT calculates the pay of time for LED down lights. http://www.ledworld.com.au/category-s/1841.htm That doesn't seem to take into account the money you spend on the heat you lose by not being able to insulate near the LED - or am I reading it wrong? The heat loss is an issue for any "downlight". I assume LED would need less ventilation than a halogen downlight.... The information I posted wasn't really about LED vs CFL Re: LED Downlights and normal lights 54Jun 16, 2012 7:48 pm SunshineT ::hyst:: urgent query - we just had insulation installed today. Despite me telling DH about the downlights and insulation issue, it had somehow slipped his mind so our insulation had 200x200 open squares around the down lights (which we learnt tonight is a legal requirement so prevent fire). There are cover / caps (which I think forg was mentioning). But just wondering - what have others with downlights done with their ceiling insulation? With gaps that wide it completely reduces the effectiveness of insulation... This is why I chose not to have downlights, I was a little bit disappointed that I paid the extra for insulation to get a 7.2 star rating yet that would be irrelevant if you have downlights I removed them from my build in the 11th hour of my build. As per: http://www.consumer.org.nz/reports/rece ... st-results The "A" in the rating (last letter), according to http://www.consumer.org.nz/reports/rece ... t-our-test means the insulation would be abutting the downlight. Obviously that's illegal in Australia, I'm not sure if you get a fireproof cover if you can do that and reduce your costs their. But then you risk increasing the heat for the downlight and shortening the globe life. The safety gap in the insulation is there for a reason so do be careful... Although compared to NZ we do have a very big gap... Re: LED Downlights and normal lights 55Jun 17, 2012 6:56 am I'm starting to think the same way theanonyuser. Even just looking at installation costs to do my entire house in LED downlights is is over $5000 ($50 per LED + $60 per light electricians fee) compared to having far fewer normal ceiling fixtures would be less than half the cost. Far fewer lights also means far fewer points of failure. Also factor in the seemingly large loss of insulation performance and increased heating and cooling costs the so called efficiency and green claims of LED downlights just don't add up. Build Thread: viewtopic.php?f=31&t=57639 Re: LED Downlights and normal lights 56Jun 17, 2012 9:50 am plucka <cut> Far fewer lights also means far fewer points of failure. Also factor in the seemingly large loss of insulation performance and increased heating and cooling costs the so called efficiency and green claims of LED downlights just don't add up. I went from 20 downlights to 9 batten points. And should get more light from the ceiling mounted lights Furthermore you *can* get LED globes into a ceiling light, its not that they only exist in downlights, that's just the current fashion trend. I also had a number of people with downlights advise that they regretted having them. Not to mention my team leader who ended up with low quality downlights/transfers which tend to blowup a bit too often, each time that means replacing it in the ceiling. Re: LED Downlights and normal lights 57Jun 17, 2012 10:29 am theanonyuser Furthermore you *can* get LED globes into a ceiling light, its not that they only exist in downlights, that's just the current fashion trend. They probably just don't offer much of an advantage when the globe can be as large as the traditional old incandescent; compact flourescents have been around in that size for years, and the light that comes out of a "full sized" compact flourescent is fine (my guess is that the problem with the downlight ones relates to the tube being too small). Re: LED Downlights and normal lights 58Jun 17, 2012 3:23 pm Hi everyone, I am following this discussion with interest. Through my research, I have almost come to the same conclusion as theanonyuser, that downlights just aren't worth it. The number that are required for general lighting, plus the cost of installation, plus the loss of insulation, just doesn't seem to make sense. At the moment, in my main living area I am planning pendants over the kitchen bench, and a matching 5-light pendant over the dining table. I'll need to find some attractive globes to put in those, as the globe is exposed. These should almost be enough light for the area, although I might need a little task lighting over the other bench - maybe some LED spotlights? I'm putting a ceiling fan over the lounge area (with a 2 x E27 light fitting - might swap out the included 25w CFLs for 13w LEDs like these). Really, these should be more than sufficient for general lighting in that area. Then, I need to find some kind of low-profile surface mount fitting to fill in some gaps. Or maybe just a couple of high powered LED downlights with a wide beam angle? I was looking at these. Any thoughts if this will be effective? Wandering off to see if theanonyuser has any more lighting info on the blog ... Re: LED Downlights and normal lights 59Nov 20, 2012 10:58 pm This thread has made for an interesting read, I've been doing some serious looking into LED, and honestly I can understand what folks are saying about there being no pay off.. if am I correct in thinking that on average you'd put in 4 x LED where you'd have a single CFL/Bayonet, the Bayonet CFL's that we've been using here (that don't seem that bright might I say) are 25w, so in theory your 4 x 12w (1400lm/90cri/12w) downlights are chewing up 48w but your getting brighter lighting...? IF you go with a single high power driver for your sets of lights you are dropping that 3-4w of efficiency your loosing for each light, and in theory if you want to reduce the amount of light you can throw in a dimmer right? So in theory with your dimmer, if you want, you should be able to reduce your power usage down to say a 30w level? anyone know if the dimmers actually reduce the amount of power the whole shibang uses in a linear fashion? from my perspective I'm inclined to install some LED's in the middle of insulation with some thermal probes and see just how hot they get... if they stay under 65 deg then consider it a win..., the other option is the insulation between floors can easily be glued to the floor above can it not? this would give you the performance without the loss? the last little trick I'm keen to try and pull off is to actually run somewhat thicker cable for each room's lights up into the first floor ceiling, this way I can have all the transformers upstairs, and even sneakier it'll make it easier to run a little PV array and a few batteries... not sure how to trigger the lights from the switch's.... using relays I guess but yeah, all light wiring into ceiling (yes I'm aware the longer the cable the larger the loss, but if it's 8 guage? Slooowwwwly getting a Manhatten 35 in Middleton Grange Re: LED Downlights and normal lights 60May 22, 2013 9:23 pm I thought I would revive this thread as all things led have moved on a bit. As the cold bites I am looking at the thermal efficiency of our house. We have a large open plan living space that was designed with Melbourne winter in mind. Lots of double glazed north glass, a very thick heated slab and tones of insulation. On the coldest sunny day the boiler (hydronic) never comes on, so by day the room is awesome. My only concern is the heat loss at night through our down lights. we have 16 gimbaled led downlights in the room. If I had my time over i would have only had 4 of them on gimbals, but they are in so now I pay the price of ignorance. I am looking at the tenmat covers mentioned earlier in this thread. The concerns raised earlier were around reducing the lifespan of the expensive led lights. I would like to know if A. anyone has these covers installed and if they help the heat loss they claim to B. if they have any reduction in led lifespan. Given Led lights are still coming down in price, the crossover in cost benefit (life vs cost of heating) is a factor now? Yes, get a builder, make sure he is experienced and a registered building practitioner 5 7552 |