Greetings. First post, so if I violate protocol, please let me know.  The new homes company I work for is interested in "going green" but we first need to learn to walk before we can run.  We'd like to start at the bronze level.  I have built about 18 Energy Star homes so the first "building block" is in place and I have been to some green building courses as has my boss, so we are not totally green on Green - sorry couldn't resist.  Anyway, I'd like to make a list of "high value" upgrades that we can use as basics for our green building.  OK - very cost effective upgrades to earn us green building points.  The ones with the most bang for the buck, both performance and points wise. We intend to build under the NAHB-Green program, however high value upgrades probably earn points in most programs.  Our location is Raleigh NC (zone 4), so that may have some bearing on your replies.  Things like geo-thermal, PV, SIP and spray foam are not in the equasion as these are cost prohibitive for our situation.  I guess you would classify this as light green building.  Granted the various components need to work toghther.   So at this point I guess I'm just creating a menu of the high value items.
Thanks in advance.

So, here is part of the list I've complied so far:
 
Points earned by manageing site work by a trained person.
Building on infill lots
Building on lots with ready access to mass transit
Orienting house within 20 degrees of south and designing glazed areas to take advantage of pasive solar heat gain.
Building homes below the predetermined sq ft size thresholds to gain resource effiency points. 
Decideout trees shading the south side during the summer.
Radiant barrier roof sheathing (cheap upgrade compared to the payback).
Home buyer education book (once we make one, each additional one will just be another version or copy) Higher Seer heat pumps that earn rebates form our local power utility.
House design that allows all ducts and air handlers to be within the conditioned space.
Engineered framing components like roof and floor trusses (which we use anyway)
Advanced framing techniques to maximize R-values of wall assemblies
FSC lumber
Covered Entry doors (good basic design - I have never built a house that didn't have a covered front door)
18" wide overhangs at the eaves and 12" at the rakes.
Flashing details shown on plans.
1.5 GPM max faucets (most modern ones are anyway - aren't they)
Rain barrel to capture rain water for irrigation.
Low VOC Paint (Not that much more $ and readily available)
Recycled carpet padding (I guess rebond satisfies this)
Green certifed carpet
Energy star bath fans (only a few $ extra)
Exhaust fans verified by our energy rater (they do that anyway)

What can you add to the list?

Good list. Orientation of the house, shading by leaving trees, overhangs, covered entries, and the last several items should be used on any house regardless of wherther it is Energy Star or not. Where you build and how big a house you build are usually in my experience) out of the hands of the builder anyway. The one thing I didn't see is increasing the insulation levels. This is often cost nuetral as you may be able to get away with smaller heating/cooling units, and the house will be less expensive to run over the long term. I'd suggest buying the REM design program-(http://www.archenergy.com/products/rem/rem_design//)- simple to use, possibly the same program that your ES rater uses, except yours won't give you the HERS rating, but it will give you an idea of the heat/cool load difference in upgrading the performance of the home. One other suggestion - buy Joe Lstiburek's book "Builder's Guide to --- Climate." There are six books, each for a different climate. (www.buildingscience.com) He is one of the most knowledgeable people in the country on energy efficiecy & proper building techniques. The book is easy to read and filled with usefull drawings & details. Good luck!

Thanks Bob. I have the book. Let me get it out and see what low hanging fruit I can find.

Hi Matt. You might add a couple additional items regarding glazing.

You can reduce the total number of windows slightly, but upgrade to a higher quality, more efficient model. This will improve building efficiency but keep overall window cost about the same.

You can also reduce the size and quantity of glazing on the west side of the building. And for the remaining west side windows, use ones with a lower SHGC. This will also improve building efficiency.

I think in general, going to R-40 in the attic is a reasonable upgrade but I doubt you'd be able to downsize the a/c at all. Most of the benefit is for heating season especially with a radiant barrier and ducts in conditioned space.

Minimizing windows is not going to go over well with the sales department. Orientation is a pretty tough on an infill lot. I don't suppose your neighbor or buyer would appreciate a bunch of south facing windows facing their side yard.

Putting ducts in conditioned space is not as easy as it seems. You better make sure that I can't hear that air handler. I am assuming that you do mostly crawl spaces so your best option would be to seal your crawl space - I've never seen one in Raleigh although it is a good idea and I'm sure they are out there (mind you I've seen a bunch of ceiling foam). I'm just not entirely sure that the code inspectors wouldn't give you a hard time. If you seal your crawl space, you still need large chases up to the 2nd floor - that eats up square footage - not a lot but it is more money than you might think. And then you have vents in the floor upstairs - you might have buyers that don't appreciate that. Then you've got to make room for the return. Usually it is in the ceiling but you can't do that anymore. So that eats up a couple more sq feet. You might find $1000 in sq footage lost. You might find sealing the crawlspace is a couple of thousand also. Add in some duct run cost and you could be to $5000. All that to save the buyer $250 a year. I am basing that number on an energy audit in our climate with conventional techniques that had duct cost at less than 20% and I am guessing that you are shooting for an HVAC cost of $1300/yr or so - which is about standard construction on a 3000 sq foot house.

I'm just saying that it is not that easy to be value based green. I think radiant barrier, low e windows, r-40 in the attic, high Seer, heat pumps with NG backup are good options. Energy star insulation techniques are a given (foam windows/doors, fiberglass always encased) I think that foam board instead of OSB on the outer walls is great if siding people don't put holes in it (or do foam on top of OSB). Obviously big overhangs in the West and add South windows when it makes sense. Sealing crawl space probably doesn't have a great return but certainly do it if you can for reasonable cost. Next is solar hot water. After that - you are into geo, foam, pv etc.

Hey - don't forget about flourescent lighting

Thanks to everyone for your thoughts.

Dpilati:

We are pretty much 100% on the same page. As it turns out the latest version of the NC Residential Code and Energy Code which are now fully adopted addresses some of these things. R-38 is now required in the attic which is only a small step away from R-40. Our ES (Energy Star) rater used to always recommend R-40 as a high value upgrade. Generally it was only a few hundred bucks above R-30 and knocked a coupla points off your HERS rating (Home Energy Rating System). Now that R-38 is required I’m not sure what our ES HERS rater will recommend but I will find out shortly. Right now I’m currently in the process of taking the attic of my own house up to R-49.

Re sealed crawl spaces, the NC Residential Code (based on IRC 2006) now has an entire section on that, and actually I even have one in the home I live in. About a year ago it was $800 for a fairly small 2 story house that I built so your guestimate of $2k for a medium sized house isn’t too far off. Part of it depends on what you use for perimeter insulation. Ours is spray foam, but rigid foam gets the job done cheaper. Sealed CS are becoming more popular here in central NC, and they are one of the main paths toward having all the HVAC in the conditioned space.

The newer codes also require Low-E windows, or at least the required specs can only be met (as far as I know) with Low-E windows. Another point for the quality home building proponents. These kind of code changes excite me – I being serous here :-).

The only thing I’m not sure about is the foam sheathing. I’m not saying it’s bad, but I’m just so afraid of potentially trapping moisture, I won’t touch rigid foam. I look very closely at the permeability of sheathing products. I wish they would come up with a structural sheathing that had a perm rating of at least 10 and an R-value of around 5 or 10, but there is none that I know of. All the siding guys I use are great at finding studs and not making extra holes, but I’ve seen other crews that were absolutely dismal at it. Some people will say that you should be OK with foam sheathing as long as the flashing details are done properly, but to me the word should is the key to that statement

Again, thanks much for your thoughts. I really like dealing with realists….

Matt - I'm curious who you work for. You probably can't tell me and that is fine but I am curious.

Good to know about the CS - we have a basement so I didn't have to go that way. There was a builder at a subdivision (off Tryon) who was building his first home and did the green thing. He wound up not sealing the crawlspace as it was a spec house. He had planned to and then didn't and I figured it was a money thing.

Now that the build is done - I am going back and doing the things that are less value oriented. I am considering sealing the attic but it looks like the only way is spray foam. I am afraid of the cost - any ideas on a 4000 sq foot house. Obvioulsy it depends, but I figure you at least know the local price. There is the 30% tax credit now that I am not new construction..... PVs are actually not bad given the incentives on the sale of the electricity and tax incentives on the install. Southern Energy quoted me $27k for a 4kw system that should make $1000 a year. After the federal and state tax credits, it isn't a bad ROI. Not for a builder to do for sure except perhaps in a special market .... ie Chapel Hill.

Posted By dpilati on 04 Mar 2010 11:30 AM
Matt - I'm curious who you work for. You probably can't tell me and that is fine but I am curious.

Good to know about the CS - we have a basement so I didn't have to go that way. There was a builder at a subdivision (off Tryon) who was building his first home and did the green thing. He wound up not sealing the crawlspace as it was a spec house. He had planned to and then didn't and I figured it was a money thing.

Now that the build is done - I am going back and doing the things that are less value oriented. I am considering sealing the attic but it looks like the only way is spray foam. I am afraid of the cost - any ideas on a 4000 sq foot house. Obvioulsy it depends, but I figure you at least know the local price. There is the 30% tax credit now that I am not new construction..... PVs are actually not bad given the incentives on the sale of the electricity and tax incentives on the install. Southern Energy quoted me $27k for a 4kw system that should make $1000 a year. After the federal and state tax credits, it isn't a bad ROI. Not for a builder to do for sure except perhaps in a special market .... ie Chapel Hill.

Dpilati:

I too live on the south side of Raleigh.  Is there a way to send an E-mail, instant message, etc via this message board? 

RE Foam - Check with Insulating Inc/FoamWorx (sp?) in Garner.  I think they do Icene (sp?). 

Re tax rebates for builders, the only thing I could find is for homes with HERS ratings at or below 50.  That's a little hard to achieve unless you have a pretty hefty energy improvment budget and then I think the cap on the rebate was $3lk or something.

Southern Energy are good people to deal with although you may be able to find someone cheaper.  There is a company south of Chapel Hill on 15-501 - can't think of the name right now.

I know some guys who are building a solar subdivision on the  southern edge of Chapel Hill.  Cool stuff, especially since there are people there who want it and have the $$$$ to pay for it.