Rigorous Data for Real Impact.

Code recognition, insurance underwriting, and widespread adoption in low-rise buildings demand hard data. We are conducting standardized testing to prove LSC's performance.

The Foundation is Set

LSC already has an official building code definition: IRC Appendix AR. LSCC's testing builds the quantitative performance data needed to take this from a residential appendix to full IBC inclusion for multi-unit buildings.

The Knowledge Library

In the 2010s, Design Coalition, Inc. partnered with the University of Wisconsin on light straw clay research. Explore this earlier research and its findings in the Straw-Clay.org archive.

Explore the research
Materials testing

Certification Pathway

From R&D to IBC Inclusion

The path from field knowledge to code-recognized building system requires six distinct phases. Here is where we are and where we're going.

Relative phase timing

Segment lengths represent relative time, not cost or exact durations. Phase date ranges may overlap.

Overall funding goal: $300,000

03

Repeatable Assembly Spec

Phase Cost$15,000

Establishing a standardized, repeatable assembly specification for the 12-inch light straw clay wall with 2x6 framing and plaster finishes — the foundation required before formal fire testing can begin.

Milestones

  • →Protocol design for all test types
  • →Lab partner outreach underway
  • →IRC Appendix AR baseline documented

The Testing Agenda

Testing costs are approximate and based on certified testing of similar bio-based wall materials conducted within the past 10 years.

01

Fire Resistance

Funding phase

Demonstrating LSC's ability to withstand extreme temperatures and prevent flame spread — crucial for low-rise viability and IBC compliance.

Test Cost$200,000
02

Humidity & Vapor

Protocol design

Quantifying how clay slip regulates moisture within the wall cavity over time in multi-unit building assemblies.

Test CostTBD
03

Sound Attenuation

Seeking partners

Measuring STC ratings for low-rise applications — party walls, floor/ceiling assemblies, and corridor walls.

Test CostTBD
04

Mold Resistance

Planning

Proving the natural anti-microbial properties of the clay-straw matrix under controlled conditions relevant to residential occupancy.

Test CostTBD

Specification Guide

Forthcoming

In the final phase of our research, we will develop practical specification guides to help designers, builders, and others create healthier living environments using bio-based building envelopes. These guides will translate our testing results into actionable guidance for reducing toxic exposures in the built environment and supporting healthier, more sustainable spaces.

What's Inside

Spec & Design

LSC Mix Design Reference Guide

Complete mix ratio tables for light, medium, and dense assemblies across 12 climate zones. Includes clay slip preparation and field quality testing.

Application

Low-Rise Application Walkthrough

Step-by-step guide for 3–4 story LSC wall assemblies. Framing schedules, form details, filling procedures, and inspection checkpoints.

Performance

R-Value & Thermal Performance Reference

Estimated R-values by mix density and wall thickness, with comparisons to fiberglass, spray foam, and mineral wool.

Materials

Clay Sourcing & Quality Assessment

How to identify, source, and field-test clay slip quality. Includes regional sourcing notes for 8 US regions.

Partner With Us

We are actively seeking partnerships with materials testing laboratories, government agricultural labs, and university programs such as Yale BioLogic and MIT Living Matter.

Are you a testing lab or university program? See our testing partnership page →