Thursday, November 17, 2011

LED Plate Lights Replace Can Lights

Home Depot has taken the lead, in offering affordable LED lighting affecting my work in attics. I can now replace a crummy can light, where too-hot bulbs pump heat into the attic, for less than $40. Where the can was foolishly non-IC, I can finish the insulation. This will be a lot more satisfying, than just replacing the can. An IC can, with a new LED bulb, is not a better deal than the plate LED.

The 14.5 watt T91 is rated at a fairly low 750 lumens, but will need dimming in many situations. Dimmed to 10%, drawing 1.5 watts, it is a beautiful night light. Somehow, lumens ratings here are not to be trusted. A 23 watt CFL rated 1600 lumens and equal to 100 watt incandescent, gives less light than the full-on T91. Please tell me whether you agree. At December, 2012, amend this post, noting photo demonstration of the equivalence of plate LEDs to light bulbs. A plate, beaming all light from a flat plane, gives twice as much illumination as a bulb. The T91 is found to be equal to a 150 watt incandescent bulb. With this recognized doubling of efficiency, why will anyone still want to use bulbs? 

The Home Depot/ Commercial Electric T91 LED Plate Light will replace 5" and 6" cans. Even this 4" Halogen spot, not as bright, that is pouring heat into an attic. 

Here is Insulation Math, for involved energy costs, where such lights have been baffled, to surround them with insulation:

Example 7: One baffled can light in every 100 sf of an "R38" attic floor. Say, cellulose twelve to fifteen inches depth. Real R38 insulation except for holes. Baffle 12" dia., area 0.8 sf uninsulated or worse, with driven leakage.
100/Reff = 99.2/38 + 0.8/3. Reff = 34.8. As if insulation were less deep by an inch or two. Why would one "waste" all that insulation, to avoid replacing the ugly can light? The baffle, with a cover in a deep insulation bed, must cost as much as the light replacement, say $60 for a T91 LED plate light in a junction box? Correct actions are achieved by prohibiting rebates if wounds and dangers in a house are not fixed.
With math for my home, the uninsulated area at each can light loses $2.4*0.8/3 = $0.64 per year. Bulb local heat is all lost in winter. Countable pennies are lost in heat-driven excess of house fresh air exchange through any can gaps

Please read more, in a Picasa Web Albums Slideshow: 

The preferred installation has replacement of a can, with a 4" junction box.

With Blogger Labels feature, find all of my discussion of these wonderful LED plate lights:

The discussion will include all LED plate lights made by Lighting Sciences Group Company, LSGC, the 6" light sold as T91 at Home Depot, and an even more useful 4" light, not yet available at Home Depot. 

At December, 2012, watch a revolution in the offering of plate LED lighting, with new Home Depot products, and hopeful availability of all LSGC plate LEDs at Lowe's stores. In arguments for new marketing measures, I offer an expansion of associated Insulation Math, above. The difficult swap-out of a can light, in the Picasa Web Album was at cost of $60, installed. With marketing efficiency and training, I suggest a $60 installed cost can be profitable to the contractor.

Typical $1 per year heat loss per can, plus excess cost of electricity. For electricity cost assume a maritime climate with $0.15 per KWH electricity cost. Consider a light that is on 4 hr per day, 1460 hr per year, Cost is $14 per year at 65 watts and $3 per year at 14 watts. Each change-out saves about $12 per year per fixture. Simple payback is in five years if total replacement cost is held at $60 per fixture. This is irreversible repair of a heat bleed, far better than putting a 23 watt CFL in the leaky can, $5 per year electricity cost, only $9 per year  saving of energy. We are looking for fullest easy, painless energy savings, not fastest payback of any investment.

Read more, picking all posts of label LED Plate Lights, on into the future. improving upon the stack nature of a blog. . CLICK HERE,

Saturday, November 12, 2011

Mouse Habitat

Kraft-faced insulation in an attic floor allows a constellation of mouse houses.

They love the alleys from on-flat header framing. Tighter quarters in lofts atop framing are not kept clean.

The best response to mice in-attic is habitat destruction, by removing the facing. Tightly fill all crevices with insulation fragments or batt trims. The facing here always did more harm than good. Smooth facing has less wind resistance, than tufty unfaced batts.

I advocate elimination of all kraft facing in new batt manufacture. Instead apply a vapor permeable air barrier facing like house wrap, as an attachment means and as  a stiller of air circulation within batts. Have as many faces as you wish in any stack. Place the face in any direction, downward in a crawl space or basement ceiling, outward on a knee wall, where the barrier serves to contain dust from human contact. I offered this idea to my favorite manufacturer, Johns Manville, in August, 2011. No response yet from JM, so let any manufacturer try it.

Wrap-faced batts should not be at the base in an attic floor.

Tuesday, November 1, 2011

Angie's List For All

With effort, I got the four reports needed for Super Service Awards in 2011, in Insulation and in Doors categories, maintaining a demonstration of validity to me as a commentor on weatherization policies. Where but at Angie's List, can I find that public comment on my exceptional work, the "carrots" I work for, and no one could buy.

It was hard because most customers would not join, even where I showed them backdoor "deals" permitting membership at $12 per year for ten years. For anyone, not just Groupon grabbers. And, why would one want only temporary membership? Perhaps the deals, and general power brokerage by phone staff, offend more even, than high prices. Knowing a business will take more from me than from another, by times-five or more, just for being naive, surely kills a deal.

It seems Angie's List could not go public, after all, to extract funds from unwary new investors, to repay it's then-majority owners, the existing investors:
March, 2011: $53.6 million, various investors including T. Rowe Price.
September, 2010: $22.5 million, investors including Milwaukee's Wasatch Funds.
December, 2008: $6 million, Prizm Mezzanine Fund, Chicago.
April, 2008: $35 million, Battery Ventures

The total from fund investors is nearing $200 million. Can't find that list seen recently. The nature of non-public ownership is evident in this comment on T. Rowe Price ownership. Say the borrowing is $200 million, and T. Rowe Price has 9.8% ownership at 601,174 shares (then of 6.13 million shares outstanding). That's an investor price of $33 per share. A share price has meaning only when the public is let in. And then, wouldn't the investors get protection in the IPO, with more share leverage. I don't know how it works, but know the public loses in an IPO.

Angie's List is in truth, the collective intelligence of it's reporting members, including me. We are being sold out for foolish, can't last, greedy investment in Wall Street, like everything else. We can resist, by asking that Angie's list never go public, but instead repay investors through income vitality. I think Angie's List could, should, must, have at least twenty million paying members. Then, even at just $12 per year per member, there would be hope the debt could be repaid. At average $30 per year, times twenty million, The List would prosper. This is my dream, and long-standing shunned-rudely proposal: Perhaps half, including new members would be Honored members, paying $20 per year. Those who don't care to actively participate, might not resist the ordinary $40 per year membership. Yes, declared same prices everywhere. No more offensive deal-making.