Monday, 29 August 2011

Lights in the bedroom

For a start, the main purpose of a bedroom is sleeping, so you have to wonder exactly what the light is for. We're going to get some bedside lights, so we can read before going to sleep. These can be fitted on, or beside, the bed. It seems foolish to permanently fit bedside lights as we may realise the bed is not in exactly the right place.

The room has a window very high on the north wall, so it should get plenty of light in the daytime. So the most likely situation in which we will really need lights is if we get up very early in the morning and need to choose which clothes to wear. There are a couple of built in wardrobes along the west wall, probably opposite where the bed will be along the east wall. The door comes in at the south east corner of the room and sliding doors along the north open into the walk-in closet. The a walk-in closet in the back has its own lights anyway, so even in the scenario of getting up really early, we may not need much light. 

The ceiling is diagonal, underneath the solar roof, but there is a horizontal part in the middle where a beam runs east-west, and a couple of ventilation ducts run alongside it. This seems like a good place to fit some lights. There are several options, below. In each
case, I'd like to choose LEDs, although in view of how little it seems this light will be used, I'm not entirely sure. In a very short time, I suspect fluorescents will look rather silly in a low-energy house.

1. A duct rail with spot lights on
2. Universal downlights that can point in different directions
3. A single, variable light in the middle of the ceiling
4. Regular downlights
5. Double LED spotlights
6. An LED strip light, running east west
7. Single LED spotlights

I started off thinking 1. The duct rail seems like a good idea, as you can move the lights back and forth and twist them around to illuminate what needs illuminating. They seem pretty expensive though, at least for LEDs. You have to get the rail, of course--5,000 yen for a 4m Toshiba rail--and any light fitting that is reasonably priced (under 2 or 3,000 yen) has "bulb not included". Maybe I'm being stupid, and I'm probably not being economical, but I have a problem with any fitting that is designed to exchange LEDs, in a country where the life expectancy of LEDs is longer than that of houses. There are, of course, some existing fittings that LED bulbs can be retrofitted into, but three lights is probably going to end up around 20,000 yen. There are some reasonable duct rail fittings for E26 bulbs, for under 2,000 yen, then with a bit of shopping around, it looks like there are LED bulbs to fit in them for 2 or 3,000 yen each for 5 or 6 watts, corresponding to a 50 or 60 watt incandescents. If the house is delayed much longer, the bulbs are likely to become even cheaper.

The architect's first plan had a row of down lights, two with universal joints to the west, to illuminate the wardrobes, and two fixed to the east. When I started looking at prices, I noticed how expensive the universal down lights were. The cheapest fixed downlight I could find with a built in LED was 3,650 yen. This was 5 watts, corresponding to a 40 watt incandescent, with a CRI of 70. For higher wattage and better colour referencing, they get more expensive. The cheapest with a universal joint was 8,620 yen. In terms of design, uniformity seems like a good idea, so if we need the lights on the west side to move around, then having a row of three of the same lights will look least offensive. Not that people are going to be spending much time looking at the ceiling. Three of these will come in over 20,000 yen.

So by the time we've made these allowances, we could just get one of the central ceiling lights that we're putting into the living room and the Japanese room downstairs. These follow the simplicity of a "traditional" Japanese ceiling light, that is stuck to the middle of
the ceiling, usually with a pull-cord dangling from it. They have two or three circular fluorescents, and a mini night light, so if you pull the cord it toggles between being on at full brightness with all the lights lit, to partially on, to just a night light. We have a couple in our house and converted them several years ago to being low-energy by taking out one of the circular fluorescents. Actually, we just didn't replace one of the tubes when it stopped working. It's still perfectly bright enough. Anyway, a year or so ago, I think Sharp brought out an LED ceiling light that looks like one of these ceiling lights, but is filled with
LEDs of different colours. It has no pull cord, instead sporting a remote control which can vary the brightness and the colour. They started retailing around 70,000 yen, and have been followed by other manufactures, and I've recently found a Toshiba light for 20,000 yen. The advantage of these lights is that they are very flexible and can fill the room with the right colour and amount of light for the circumstances. They have remote controls so, although the manufacturers recommend you add a wall switch, you don't really need one and can fit a holder for the remote control wherever you like on the wall. I think this won't look so good on the bedroom ceiling though.

Another option is to just put a row of regular downlights east to west. If they send out a 55 degree beam it should cover all of the floor and most of the wardrobe, except possibly the top right and top left corners. These lights should be bright enough and would look good. This solution would come in a little under 20,000 yen.

It would also be possible to put a double spotlight bracket on the ceiling, pointing to the wardrobes. One of these is available from Odelic for 11,000 yen, but I'm not completely sure it comes with bulbs. There's another from Koizumi for 15,000 yen, also with exchangeable bulbs, I think included. If we put a double spot to the west, then for aesthetic balance we should put another double spot to the east. This solution would also come in a little over 20,000 yen.

Another option is LED strip lighting. This should be an economical option as strip PCBs with LEDs added every few centimetres are cheap, however one problem is the fittings. There are some from Neo blue 1.2 metres long for 13,860 yen. These run on 24 volts DC, so a transformer is necessary. It would be easy to dim them, but I don't think dimming is a high priority for this room. Either we want it light or dark. There are some 100 volt strips from Mini Bee for around 10,000 yen for 90 cm. There's also a 590 mm strip from Noatek for 2,700. Most of these cost around 1000 yen per watt of LED. There's a 420mm strip for 1750 yen that is about half that, but
it is 12V and needs a power supply. All of these are manufactured outside Japan. Another problem with these is how bright they will be. This kind of lighting seems to work very well inside cabinets, for corridor lighting or for ambient lighting, and it will certainly stop the room from being dark. It may not be bright enough to help choosing clothes. As the light comes in strips, it could run along the edge of the horizontal bit of ceiling and would be practically invisible when not on. This kind of lighting fits the lines and spaces of buildings and the manufacturing processes of LEDs, but at the moment it doesn't fit into the imaginations of architects, the mindsets of electricians or into the spaces in the market.

Option 7 is then single bracket spotlights, arranged in a row from west to east. Three would probably be enough, if they are wide-beam. Again we're limited by the range and cost of spotlights, which seem to start at 7 or 8,000 yen with bulbs built in or included.

After the first round, I think we can eliminate 2, 3 and 6. The more I look at it, the better the duct rail of spot lights seems. It will probably come out cheapest, and has the advantage that if it's not bright enough, we can get another couple of fittings to put in there, or replace the bulbs with higher wattage ones, notwithstanding my earlier comments about the irreplaceability of non-replaceable LEDs. There are some 12 watt bulbs for 7,500 yen and 16 watts for 8,200 yen. Those prices will probably halve in the next year.

Low cost and high flexibility. So I'm back at my original idea and it seems like I've been wasting my time prevaricating and writing this. I hope it wasn't a waste of time to read it!