I am looking for energy audit software right now. We have a common problem, a 1973 house with some built-in energy inefficient features of that time. The two biggest problems are single pane glass (with built in storm windows - providing U values somewhere between that of single-pane and double pane) and no insulation in the walls. Both of these are fixable, but at a price.

We are fortunate to have a high-efficiency gas furnace, 5 year old higher efficiency AC system and fully insulated attic (the low hanging fruit of energy efficiency!).

... here are some online energy audit options I have found:

Zip code insulation program http://www.ornl.gov/~roofs/Zip/ZipHome.html
Fast AND easy to use. This program has simple, easy to understand suggestions for us:
1) Blow insulation into any uninsulated exterior wall cavity. R-13
2) Insulative sheathing on empty wall, R-5, but only if the exterior siding is removed for some other purpose - like a very costly siding replacement!
3) Basement wall interior - R-11. An option I am not thrilled with, because we just recently painted the basement. But we do have huge amounts of above and below ground basement wall. Did I mention the house is large?

Rehab Advisor http://www.rehabadvisor.pathnet.org/index.asp
Suggestions:
1) Insulate Attic - Insulate your attic to a minimum of R-49. Install vapor retarders in non-vented framed ceilings. (already done!)
2) Seal Duct Leaks - Have your ducts professionally sealed to reduce leakage to the ENERGY STAR specification of 10% maximum. 1.5 year payback expected
3) Insulate walls
4) Seal Air Leaks - Have a professional seal your home's air leaks. Typically, this reduces air leakage by 25%. Expected cost $554 with a 2.8 year payback
5) Windows and Skylights - When replacing your windows or skylights, choose ENERGY STAR qualified windows with a U-Factor of 0.35 or less and skylights with a 0.60 or less. Expected cost $744 with a payback of 2.4 years. [Clearly, this is extra cost for energy efficiency over the cost of a standard window replacement.]
6) Reflective Roofing Materials - When replacing your roof, choose reflective, light colored shingles to prevent increased heat transfer in the attic.

Home energy saver http://hes.lbl.gov/
This is a very detailed calculator, but it has some slightly confusing results. It predicts that upgrades to our home will drop total energy costs (gas + electric) from $3860 to $1549. The problem is, our actual energy usage is only about $2500 per year. (1100 CCF natural gas and less than 10,000 KWH electricity)

HES suggests Air sealing, high efficiency dishwasher and 3-pane low E argon windows.
Here is what it says about the windows:
"Estimated Annual Bill Savings: $98
Estimated Lifetime Energy Cost Savings: $2940
Upgrade Cost: $1681 above the cost of standard windows
Return on Investment: 4%
Upgrade pays for itself in: 17 years"

The HES program gives conflicting advice on R-11 blown in wall insulation.

Last week, an idea occurred to me - getting into the home energy audit business. There is a real need for this service here. I have been looking into what training is required.

There is a jumble of competing organizations in the home inspection certification business. I took the InterNACHI exam "only 40% pass" and completed with a passing grade while half asleep with no studying or other prep. Surely there is a higher standard?

It appears that in PA, I need home inspection licensing to do home energy audits.

AIA American Institute of Architects
AII American Institute of Inspectors http://www.inspection.org/
AIBD American Institute of Building Design http://www.aibd.org/ Membership $420 per year
ANSI American National Standards Institute
ASHI American Society of Home Inspectors http://www.ashi.org/
ASNT American Society for Nondestructive Testing http://www.asnt.org/certification/generalinfo.htm
BPI Building Performance Institute http://www.bpi.org/index.htm
EPBHI EXAMINATION BOARD OF PROFESSIONAL HOME INSPECTORS - National Home Inspectors Exam http://www.homeinspectionexam.org/ $225
EEBA Energy and Environmental Builders Association
IICRC Institute of Inspection, Cleaning and Restoration Certification
InterNACHI - free online entrance exam http://www.nachi.org/nie.htm "only 40% pass!"
LEED Leadership in Energy Efficient Design
NAHI National Association of Home Inspectors http://www.nahi.org/
NACHI National Association of Certified Home Inspectors membership $289 per year
NCQLP National Council on Qualifications for the Lighting Professions
NATE North American Training Excellence
NERA National Energy Rater Association http://www.energyraters.org/
RESNET Residential Energy Services Network http://www.natresnet.org/ HERS Home Energy Rating System

Some training options:

AHIT Distance Learning Master Course $995 http://www.ahit.com/training/conted/index.cfm

Level I Infrared Thermography $1695 http://www.infraspection.com/courses_distance_learning_general.html

Infrared Inspections for NACHI Home & Building Inspectors $500

http://www.accustarlabs.com/training_classroom.php (Radon)

http://www.cmcenergy.com/ http://www.hometuneup.com/

http://www.homeenergy.org/contrainingguide/index.php#pennsylvania

Opinions sought - where does one start? What is the most important/best/most helpful home inspection nonprofit org?