# Presentation: 025243

## The Residential Code of the Future2005 National WorkshopBuilding Energy Codes ProgramJune 28, 2005

- Z. Todd Taylor
*Pacific Northwest National Laboratory*

## What Future?

- future (‘fyoo-ch&r) – *noun*
- September 28 thru October 2, 2005
- March 24, 2006
- Thereafter

## What Future?

- future (‘fyoo-ch&r) – *noun*
- 2006 IECC – What will happen at the Final Action hearings?
- 2007 Supplement – Change proposals are due 24-March-2006
- Visionary future – General directions DOE or others might try to move the code

## DISCLAIMER:Nothing presented here is anything more than an idea, a prognostication, an opinion, or a mistake(well, almost nothing)

## (1) The 2006 IECC Future

## The 2006 IECC Future

- No *major* changes made to 2004 Supplement at Feb/Mar Code Development hearings
- Original “floor mods” continue to be controversial (+R2 wall requirements in zones 3 and higher)
- DOE’s original proposal had R13/R19 requirements
- Modifications “from the floor” raised those to R15/R21 at the Sep-03 Code Development hearings; these survived Final Action to become part of 2004 IECC Supplement
- Several proposals to roll back to R13/R19 rejected by IECC committee at Feb/Mar hearings
- Anticipate “public comments” to overrule committee at Final Action hearings
- Predicted outcome:

## The 2006 IECC Future

- Why do the floor mods matter?
- Not much energy on the table (maybe 1% to 2% depending on location and wall type)
- Builders can be picky about wall construction
- IRC energy chapter still at R13/R19
- First time IECC and IRC have differed substantially
- States might selectively adopt one or the other
- DOE tools will support...one?  the other?  both?  neither?

## The 2006+ IECC/IRC Future

- Possible future efforts related to IECC/IRC differences (not necessarily by DOE):
- Scale IECC back to match IRC
- Scale IRC up to match IECC
- Convince ICC to merge IECC and IRC (have them managed by a single committee)
- Embrace differences and chart parallel courses
- IRC becomes the “baseline” model code
- IECC becomes the “stretch” model code
- What about DOE’s EPAct-mandated “determinations”?

## (2) The 2007 Supplement Future

## The 2007 Supplement Future

- Possible DOE change proposals
- Minor (or major) fix-ups
- Minor efficiency improvements
- Major efficiency improvements

## The 2007 Supplement Future(Possible Fix-ups)

- Clarify conditioned crawlspace requirements/definitions
- Tweak performance path to align with latest RESNET/Tax-Credit goings on
- Tweak performance path to eliminate overhang free-rider
- Clarify fire blocking requirements under unvented, cathedralized attics

## The 2007 Supplement Future(Possible Fix-ups, cont’d.)

- Revamp vapor retarder requirements
- Add trade-off limits to R-value requirements
- Remove or moderate credit for hydronic systems in oil-dominated regions (current free-rider issue)
- Other ideas?

## The 2007 Supplement Future(Possible Minor Efficiency Improvements)

- Increase crawlspace wall insulation requirements in cold climates
- Extend basement insulation requirement to zone 3
- Require mastics or drawbands to supplement tapes on ductwork (a-la CA Title 24 language)
- Other ideas?

## The 2007 Supplement Future(Possible Major Efficiency Improvements)

- Mandatory duct testing
- Mandatory whole-house pressure testing
- Limits on “bad glass” in the South
- Penalty for ducts outside conditioned space
- Mandatory HVAC sizing calcs and/or verification of refrigerant charge
- Down-weighting of HVAC credit against envelope
- Expanded scope of code
- Lighting?
- Appliances?
- Other?

## (3) The Visionary Future

## The Visionary Future

- The state of the code today
- Still allows houses to consume energy
- Most components have plateaued (LCC-wise)
- Requires too much attention to achieve _minimum_ efficiency (leaving little tolerance for efforts to achieve _optimum_ efficiency)
- The *powers that be* only care about pass/fail (i.e., “How much better” buys the builder nothing at the code office)
- Code is rigid and legalistic, whereas achieving advanced performance requires imagination and engineering
- Code is legally and practically limited in scope
- No single entity controls the code

## The Visionary Future

- So what might be done to the code?
- Max out component requirements
- Focus compliance on performance path
- Expand scope to include more than HVAC & H2O
- Forge better linkages with beyond-code programs, tools, and marketing

## The Visionary Future(Shall we max out component requirements?)

- Some components have room for improvement
- Most components are plateaued (or at least have potential returns too low to be worth the battles)
- Even with all components maxed out, we’re nowhere near zero energy buildings
- Code has limited scope
- Code not designed to optimize, exploit interactive effects
- Conclusion:  Some components can be improved but this is not the wave of the future

## The Visionary Future(Shall we focus on the performance path?)

- Does allow accounting for interactions
- Code (and code officials) still don’t care
- Infrastructure not there (yet) in much of U.S.
- Conclusion:  More performance compliance is probably inevitable, but it won’t _lead_ the way to the future

## The Visionary Future(Shall we expand the scope of the code?)

- To approach ZEB we must consider more than just HVAC and H2O
- However, while the code might cover all energy end uses, it can’t *legally* cover all house components
- Not all components can be *practically* regulated by the code (e.g., appliances not sold with the home)
- Conclusion:  Expanded scope will help, but isn’t likely to cover everything necessary for ZEB

## The Visionary Future(Shall we forge linkages with beyond-code programs?)

- Allows consideration of things not covered by the code
- Builds on infrastructures developing in a (potentially) profitable business climate
- Gives meaning to “how much better”
- Builder incentive
- Consumer education
- Typically not easy to map beyond-code results (e.g., HERS ratings) to code compliance (based on equivalence of UA, energy, or energy cost)
- Conclusion:  The Future Code must fit with beyond-code programs, but there is work to be done

## The Visionary Future(Conclusions)

- TBD