# Presentation: 323005

## DOE’s IECC Code Change Proposal

- Development of the Prescriptive Criteria

## Residential IECC Code Changethe “RICC”

## Impetus for the RICC—the two most common comments about the IECC

- “Too complex”
- “Doesn’t deal with cooling”

## Primary Goal of the RICC

- “***A substantial improvement in usability***”

## Or.....

- “Compliance, not just stringency”
- “Compliance, not just enforcement”
- Make adoption and enforcement easy, but...
- ...work in the absence of enforcement as well
- “Require what’s worthwhile and practical, eliminate what doesn’t happen anyway”

## How Energy Codes Work

- “Chop off the lower tail”
- “The worst house allowed by law”

## Slide 7

## Slide 8

## Slide 9

## Focus on usability, format, falling off a log
Leave stringency alone (mostly)
Defer controversial issues to future years (mostly)
Hope for a proposal everyone supports
Expect a proposal nobody (seriously) opposes

- Leave stringency alone (mostly)
- Defer controversial issues to future years (mostly)
- Hope for a proposal everyone supports
- Expect a proposal nobody (seriously) opposes

**General Approach—A “Friendly” Amendment**

## Strategy to Improve Usability

- Shorten, simplify, disambiguate, close loopholes
- Consolidate geographically
- Honor political boundaries
- Homogenize baseline requirements
- Incorporate cooling into zone definitions
- Scratch a few common itches
- Leverage manufacturers for enforcement

## Brass Tacks—Key Characteristics of DOE’s Change Proposal

- Redefined climate zones
- Eliminated dependency on window area percentage in the prescriptive path
- All the *little* things

## Climate Zones—Redefinition Goals

- Reduce number of zones
- Consolidate residential and commercial
- Honor political boundaries
- State, county lines
- Metropolitan areas and pre-existing jurisdictional boundaries
- Balance heating and cooling considerations
- Eliminate need for climate data

## Climate Zones—Process

- Consultation with others
- ASHRAE
- Energy Star
- Building America
- States, etc.
- Detailed climatic evaluation (30-year hourly histories, cluster analysis, etc.)

## Slide 15

## Climate Zones—Process

- Consultation with others
- ASHRAE
- Energy Star
- Building America
- States, etc.
- Detailed climatic evaluation (30-year hourly histories, cluster analysis, etc.)
- Leaning on old knowledge (Koppen classification)

## Slide 17

## Slide 18

## Current IECC Climate Zones

**Current IECC Climate Zones**

## Window Percentage Dependency—Why Eliminate It?

- Enormous reduction in overhead
- Requirements don’t squirm with design changes
- No multiple tables required
- No calculations required
- No take-offs required
- No measurements required

## Window Percentage Dependency—Why Eliminate It?

- Eliminates irrational behaviors
- Large homes allowed to be looser than small ones
- Inefficient aspect ratios allowed to be looser
- Design changes that reduce energy can flunk the house
- Complying additions/renovations difficult except for large (i.e., energy-hog) homes

## Window Percentage Dependency—Why Eliminate It?

- It’s the right thing to do (LCC-wise)
- It appears to work (name a jurisdiction with a tight code and 100% compliance)

## Window Percentage Dependency—Is Eliminating It Justified?

- Windows aren’t the losers they used to be (low-E, vinyl, 0.4 SHGC, etc.)
- Regulating percentage regulates the wrong thing anyway (or at least has very low ROI)
- Area (not percentage) is the real issue
- Orientation is the real killer
- Decision:  Cover all bases and increase complexity?
- Market forces usually do the job anyway

## Window Area Studies

| State | Num. Houses | Window Pct. | Notes |
| --- | --- | --- | --- |
| WA | 157 | 14.8 WFR | 
Ecotope, 2000 |
| OR | 44 | 15.2 WFR |  |
| ID | 104 | 12.7 WFR |  |
| MT | 61 | 13.1 WFR |  |
| PA | 60 | 12.4 WWR | PHRC, 2000 |
| AR | 100 | 12.3 WWR | Evan Brown, 1999 |
| FL | 423 | 16.8 WFR | FPL, 1995 |
| CA | 3200 | 15 to 18 WFR | Six studies, 1990-2002 |

## Window Area Studies, cont’d.

| State | Num. Houses | Window Pct. | Notes |
| --- | --- | --- | --- |
| VT | 290 | 13 to 15 WWR | Two studies, 1999-2002 |
| MA | 186 | 14.5 WWR | Xenergy, 2001 |
| NH | 1000+ | 13.5 WWR | 2003 |
| CO | 80 | 11.6 WWR | 2002 |
| Nat. | 120 | 16.7 WWR | ASHRAE RP 904, 2002. 
Includes doors |

## Slide 26

## Window Percentage Dependency—Is Eliminating It Justified?

- Windows aren’t the losers they used to be (low-E, vinyl, 0.4 SHGC, etc.)
- Regulating percentage regulates the wrong thing anyway (or at least has very low ROI)
- Market forces usually do the job anyway
- Enforcement usually doesn’t do the job anyway

## All the Little Things

- Requirements reference purchasable products (e.g., R-values, not U-factors)
- Trade-offs based on cost, not BTUs
- Scratch common itches (termites, hurricanes, cathedral ceilings, basement insulation, etc.)
- Correct vapor barrier errors
- Eliminate the unenforceable (e.g., no pool cover if pool heater is 20% “renewable”)
- Eliminate unused/redundant/conflicting definitions
- Require sealed air handler

## The Prescriptive Table

- “***A substantial improvement in usability***”

## Resources

- Text of proposal (web page)
- Climate analysis (web page & ASHRAE papers)
- Window-area analysis (web page)
- 		_[http://www.energycodes.gov/](http://www.energycodes.gov/)_