Fluorescents are currently the king of the lowest initial cost, high output, long running time category. Like wws944 said, the typical fixture/ enclosure used could dramatically cut the actual usable output. I was initially loath to give up my recessed fluorescent light box, but the benefits of having a higher ceiling forced the decision. In the end, the Lr6 downlights worked out far better than the original.

Before I launch of into the ether, LavenderLass..... Your husband is doing OK now, and y'all are over and out of perils and pitfalls that befell y'all? This is gonna be a fairly long ramble, 'cause I’m really good at such things, and I sorta kinda in a way wanna brag about it all anyway..... We started on our new place at the end of this past June. Well, if you count the well and septic as starting, it was the first week of June We have a nice 1888 sq ft house on a couple of acres surrounded by a couple of acres of county owned "Storm water run off ROW" right down town here in the middle of the big city, Well, OK, with the "finished basement" I reckon it's really more like 3456 sq ft, but around here nobody counts a finished basement as part of the house. It's kind of just expected. We have always had a place way out in the sticks since we first got together 33 years ago. We had a really nice almost 2.5 miles off the road down a private ROW in the middle of an Appalachian foothills hollow out of the way almost 40 acres that we bought when the kids started middle school and we decided I was keeping the "new" job and that we would move closer to the real world than our 105 acres in the middle nowhere Tennessee was. Then a moron in a great big hurry passed a school bus on a curve and there I was. To make a real long story short enough to bear, everybody but me thought that being a "Neurological disaster area" that far off the road with no neighbors and cell phone service only if you're in the right spot is totally unreasonable. My wife said she would be OK with me finding a place just as country just half as close to home (which would have been 13.75 miles) and half as far off the road with a neighbor or two...... Which of course no one thought I would ever be able to do. So, I asked everyone everywhere that I came across and looked and looked and drove down every un-named pig path around and at last found a very nice 17.3 acres located almost right where three counties meet right in the very middle of the NC Piedmont. Unbelievably rural for considering its' being just 7.5 miles from the square in the booming metropolis of Mocksville, NC. and pretty much equi-distant to Salisbury, Lexington, Statesville, and Wake Forest University/Baptist Medical Centerin Winston-Salem. And it's just 47 miles to the terminal entrance at Piedmont-Triad International Airport in Greensboro, NC. and 67 miles to the terminal entrance at Charlotte-Douglas International Airport in Charlotte, NC too. C was at first in shock that I actually found such a place and was a tough sell on me getting us this, but she finally realized that I was never going to shut up about it said if I could swing the deal that she would sign her name on the dotted line right next to mine. Everybody concerned, the people selling it, the real estate agent, the neighbors, the county folks, the people down the road, everybody, said we were never going to get it at what I was willing to pay. Everybody, except me of course, had little enough faith in my unfathomable charm and and bull dog (though many call it bull something else) tenacity to think that I would ever be able to talk us into making such a deal. But, I DID! And so C just like she said she would ended up signing her pretty little signature right next to mine and it's since Dec 2013, it's ours..... Very private at a little over 1.3 miles off the pavement across three cattle grates through pasture and woods down an excellent shared private drive with one neighbor 500 - 600 feet distant on each side of the home-site. A school teacher couple with no kids on one side, and a retired serviceman and wife on the other, and an absolutely palatial estate behind across the river. Due to the location on an oxbow of the river, and being in a three county "Designated Agricultural District", that's all the neighbors there will be. And the "Designated Agricultural Area" is bigger than this whole one town one high school county of maybe 40,000 is, and near as I can tell has a population density of 32 per square mile, which for east of the Appalachians, especially in the Ga/SC/NC/Va Piedmont, means it's virtually empty. Sort of a pie shaped property with almost 2100' on the S Yadkin River. From a +75' bluff above the river down to several hundred feet of actual real sandy beach right down along and with two great big and deep swimming holes including one with a great big rock sticking up right in the middle for an excellent diving platform into its' 12 - 13 foot deep hole, with 300' fronting the "drive", +3000' along the longest side of the property with +1200' along the "opposite" side. And the river is from beginning to end one of the very few NC state "Protected Watershed"s and there willnever be any kind of development adjacent to it, no industrial plants, no sewer plants no nothing except woods and farmland. C had serious doubts about the rational of buying this place, but, the chances that anybody could now talk her into selling bit and buying something else, are substantially less than zero..... Approx. 5.5 acres of very nice and healthy pasture/field - with close to 12 acres in large mature hardwood's from level river-front floodplain to gently sloping to fairly steep hillside. And several acres of those hardwoods down in the flood plain that will one day make another several acres of beautiful shaded summertime pasture too. We have us a new permitted and tested and approved 282' well with static water at 60', and a new permitted and tested and approved septic system installed. We bought a really odd 14 X 68 half of a double wide with an odd 2 separate pitches roof that we stripped out from end to end and is now in the process of being completely and totally ever so slowly redone by ME formerly 2 bed/2 bath - now being turned into a luxurious 960 sq ft 1 bath, 1 bedroom with a small alcove, an entrance-hallway/laundry/closet, a 9'6" X 13' "spare" room (for ME!), and a large sewing room and walk in closet. VERY rustic in the outside appearance as the neighbors are like minded and none of us are concerned with what the drive by traffic that will never be, nor are any of us about impressing the county tax folks or anybody else except for the Great Blue Herons, Beavers, Bald Eagles, Deer, Turkey, Fox, Bobcats. Rabbits, Raccoons, Skunks, Possums, Wood Ducks, and according to one local lunatic, Bigfoot too, that are all in abundance here. A wonderful retirement place for us, our now grown and hopefully permanently gone kids, our 5 dogs, horses, cattle, goats, and chickens, and our peace of mind too..... You could look and look, but it's it's absolutely no exaggeration to say that no one will ever find another "almost like being in the mountains" place like this anywhere in all of the Ga/SC/NC/Va Piedmont. OK. The youngest of the great big Great Pyrenees wanting to go out and play in the snow, I am done with my brag..... As next week is the first time this season since early November that we'll see temperatures hit 60F, work is about to once again, begin in earnest. And regular reports of perils and "progress" and pic's too are soon to follow.

OK, lets see how it works with a different "rule of thumb" using Galculator (http://galculator.sourceforge.net/), capable of operating in RPN like an HP-15C does and saving me from having to locate mine. Or you can ignore my plug for Galculator and follow using mental arithmetic because the numbers here are all simple. A space of 48 by 27 inches is 9 square feet. Multiplying by 90 cfm/sq.ft yields a desired flow rate of 810 cfm. Duct losses are negligible, but baffle, transition, and MUA losses may be significant. Without more information (particularly a fan curve), we might stick with a nominal fudge-factor of 1.5 for working at some pressure drop on the fan curve. This yields a zero static pressure blower rating of 1215 cfm. 1200 is close enough. If the blower input is designed for a 10-inch duct and the hood output is designed for a 10-inch duct, use a 10-inch duct, even if you have to frame out the studs to accommodate the location. Otherwise, the necessarily abrupt transitions needed to get down to 8 inches and back up to 10 inches within a foot will have some turbulence-caused pressure loss and noise you don't need. kas

We estimate siding by the square foot of coverage, which considers overlap and waste. Its usually ordered and priced by the lineal foot. That should be your consistent go to & how you communicate with the supplier. The BF number may be how they purchase it wholesale, how traders buy futures etc. Of little use to you as you're dealing with a highly processed specialty material, not a box car load. 144 cubic inches is a board foot. (1x12x12, 1x8x18, 2x6x12, etc) A 1x8 board prior to milling is .667 BF. This is likely 3/4" x 7-1/2" less lap, so it might be 7" coverage. Ask the supplier.