DAYLIGHTING

During scientific tests of its solar properties, it was discovered that PTFE fiberglass membranes reflect approximately 72-75 percent of the sun’s radiated solar energy while allowing in approximately 8 to 20 percent of natural daylight to permeate the membrane depending on the strength and thickness of the material.

Membrane Comparisons

Property:PTFE FiberglassPVCETFE FilmePTFE
(High Translucency PTFE)
Translucency10-18%10-20%Transparent20-40%

Membrane structures can also contribute to Leadership in Environmental and Energy Design (LEED) credits in such categories as daylighting, innovative design and reduced or recyclable material usage.


LEED Rating System: EBOM

LEED 2009 Credit: EQc2.4

LEED Credit Overview: Daylight & Views - Through simulation, the prescriptive path and/ or measurement show that at least 50% or more of all regularly occupied spaces are day lit.

Sheerfill PTFE Membrane – woven fiberglass with Teflon coatingSolar Transmission: 10-21%
Visual light transmittance not listed.
Sheerfill PTFE Membrane w/ EverClean – woven fiberglass
with Teflon & TIO2 (self-cleaning coating)
Solar Transmission: 10-21%
Visual light transmittance not listed.
St. Gobain ETFE Membrane – transparent filmVisual light transmittance: 91.7%- 40.5% VLT
for color variations other than white dependent
on printing area.
Tenara ePTFE Membrane – very high translucent membraneVisual Light Transmittance: 15%- 40%
Tensotherm Insulated Membrane – translucent insulated
membrane composite using aerogel blankets
Visual Light Transmittance: 15%- 40%

LEED Rating System: NC, CS

LEED 2009 Credit: EQc8.1

LEED Credit Overview: Daylight - Achieve day lighting in 75% of all regularly occupied spaces.


Sheerfill PTFE Membrane – woven fiberglass with Teflon coatingSolar Transmission: 10-21%
Visual light transmittance not listed.
Sheerfill PTFE Membrane w/ EverClean – woven fiberglass
with Teflon & TIO2 (self-cleaning coating)
Solar Transmission: 10-21%
Visual light transmittance not listed.
St. Gobain ETFE Membrane – transparent filmVisual light transmittance: 91.7%- 40.5% VLT
for color variations other than white dependent
on printing area.
Tenara ePTFE Membrane – very high translucent membraneVisual Light Transmittance: 15%- 40%
Tensotherm Insulated Membrane – translucent insulated
membrane composite using aerogel blankets
Visual Light Transmittance: 15%- 40%

Coated fabrics like translucent PTFE fiberglass and transparent films such as ETFE, are available in ranges from 10 to 90 percent.