Next-generation building insulation materials

We are looking for fire resistant high performing insulation materials priced affordably enough to be used in walls.

Problem
Traditional insulation materials are generally environmentally unsustainable and either combustible or difficult to install.

Desired properties
Non combustibility, sustainability, durability, and shapeability.

Category:
Deadline for concept summaries: August 31, 2018

Category 4: Next-generation building insulation materials
Environmentally sustainable, noncombustible, and shapeable

Problem statement

Until today, the vast majority of building construction has utilized foam plastics (i.e. EPS and XPS) or mineral wool for thermal insulation. These materials are generally environmentally unsustainable, and low-cost competitors have commoditized the global market. Recently, catastrophic fires in London and the Middle East have caused architects and developers to move away foam plastic and other combustible insulation materials. Mineral wool, although noncombustible, is difficult to install and limits options for building design. The table below summarizes the properties of common insulation materials.

Properties of common insulation materials

EPS XPS Mineral wool Target Stretch
Thermal R-value R-3.8 per in. R-5.0 per in. R-4.0 per in. R-5. per in 0 R-8.0 per in
Water absorption 4% 2% > 20% 20% or less 5% or less
Combustibility High High Low Low Meets E136
Compressive strength 10 psi 25 psi 4 psi 25 psi 50 psi
Weight density 1 lb / ft³ 1 lb / ft³ 7 lb / ft³ 6 lb / ft³ 2-3 lb / ft³
Installation Easy Easy Difficult Easy Easy +
Cost per board-foot $0.13 / bd. ft. $0.45 / bd. ft. $0.78 / bd. ft. $0.50 / bd. ft. $0.25 / bd. ft.

Possible approaches

Any materials that provide effective thermal insulation while being environmentally sustainable, noncombustible, shapeable, and easy to install will be considered. Example solutions include insulation beads fused together with resin, polymer-based insulation derived from sustainable materials using a low tech, low energy manufacturing process, and other noncombustible insulation materials.

Known approaches not of interest

Unless significant performance/cost breakthroughs or innovative applications can be achieved, the following materials represent known state-of-the-art and are thus not of interest:

  • Foam plastics similar to EPS and XPS
  • Mineral wool
  • Wood-based insulation

Success criteria

Required:

  • Noncombustible
  • Environmentally sustainable
  • Non water-sensitive
  • Dimensional stability
  • Durability of masonry and high impact resistance (“woodpecker” and “golf ball” damage)
  • Can be extruded, molded, formed, or compressed into shapes
  • Can function as continuous insulation on the exterior of buildings
  • Can be installed by the plastering, masonry, or carpentry trades

Desired:

  • Commercially available in 3 to 5 years
  • Produced from biological / natural processes
  • Drainable medium that can evacuate water quickly
  • High water vapor permeability

Technical specifications [Cat. 4]: Next-generation building insulation materials

Property Standard Requirement
Thermal resistance ASTM C518 R-value 5 per inch or greater
Water absorption ASTM C272 Less than 5%
Water vapor transmission ASTM E96, Method A Greater than 10 perms
Surface burning ASTM E84 Flame spread: 0

Smoke developed: 0

Combustibility ASTM E136 or NFPA 220 Noncombustible
Density

(desired, not required)

ASTM D1622 2 lb/ft3
Compressive strength

(desired, not required)

ASTM D1621 25 psi or greater