Skip to content

Ohio 2024 IECC cost-effectiveness tool

This guide explains the EEHM Vault analysis tools for the people who use them: energy raters, reviewers, and EEHM staff. The first tool is the Ohio 2024 IECC cost-effectiveness tool.

What the tool does

The tool compares two versions of a home:

  • A baseline model built to the 2019 Ohio Residential Code.
  • One or more proposed models that add 2024 IECC efficiency improvements.

It then answers one question: over a 30-year period, do the energy savings from the proposed improvements outweigh their added cost? It produces the numbers an Ohio code-compliance reviewer needs to make that call.

The three methodologies

The tool combines three established methods:

  • R408 credit selection — Ohio's prescriptive credit pathway. You pick the efficiency measures the proposed home uses and confirm it earns enough credits to comply in both Climate Zone 4 and Climate Zone 5.
  • PNNL lifecycle cost (LCC) — a 30-year net-present-value calculation based on the U.S. Department of Energy / Pacific Northwest National Laboratory method. It turns energy savings and up-front costs into a single dollar figure.
  • Cost Bridge Table — a structured way to price the proposed improvements, matching the equipment in each model against a reviewed cost catalog.

Baseline versus proposed

Every comparison has exactly one baseline model and up to six proposed models. The baseline represents the code-minimum home. Each proposed model represents one packaged set of improvements you want to evaluate. The tool always measures savings and cost as the difference between a proposed model and the baseline.

Who it is for

  • EEHM staff create analyses, load models, and manage who can see them. Staff can edit every part of the tool.
  • External reviewers (energy raters and code reviewers) are granted access to a specific analysis. They can work through the R408 and lifecycle-cost tabs, and — when staff enable it for them — the Cost Bridge Table.

See Getting started for how access and sign-in work.

The five tabs at a glance

The tool is organized as five tabs you work through in order:

  1. Model Library — load the baseline and proposed models from Ekotrope. See Manage models.
  2. Code Comparison — a reference table contrasting the 2019 Ohio code with the 2024 IECC.
  3. R408 Credit Selector — choose the proposed home's efficiency measures and confirm credit compliance. See Select R408 credits.
  4. LCC Engine — enter costs and run the 30-year lifecycle cost calculation, including the Cost Bridge Table. See Enter LCC inputs and Use the Cost Bridge Table.
  5. Results Dashboard — review the combined results and print a one-page PDF deliverable. See Read results and print the PDF.

New terms used throughout this guide are defined in the Glossary.