Question? Just ask us!
Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
InspectAPedia ® Home
INSULATION INSPECTION & IMPROVEMENT
ACOUSTICAL SEALANT CHOICES
AIR LEAK MINIMIZATION
ASBESTOS IDENTIFICATION IN BUILDINGS
BASEMENT CEILING VAPOR BARRIER
BASEMENT HEAT LOSS
BUCKLED FOUNDATIONS due to INSULATION?
CATHEDRAL CEILING INSULATION
CATHEDRAL CEILING VENTILATION
CEILINGS, DROP or SUSPENDED PANEL
DEW POINT TABLE - CONDENSATION POINT
DUCT INSULATION, ASBESTOS PAPER
FIBERGLASS PARTICLE CONTAMINATION
FIBERBOARD INSULATION SHEATHING MOLD
FIBERGLASS INSULATION MOLD
FIREPROOFING ASBESTOS SPRAY-ON
FRAMING DETAILS for BETTER INSULATION
FRAMING DETAILS for DOUBLE WALL HOUSES
FRAMING METAL STUD PERFORMANCE
FREEZE-PROOF A BUILDING
HEAT LOSS in BUILDINGS
HEAT LOSS PREVENTION PRIORITIES
HEAT LOSS R U & K VALUE CALCULATION
HOUSEWRAP AIR & VAPOR BARRIERS
HOUSE DOCTOR, how-to be
HUMIDITY LEVEL TARGET
ROOF ICE DAM LEAKS
INSULATION AIR & HEAT LEAKS
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INSULATION FACT SHEET- DOE
INSULATION INSPECTION & IMPROVEMENT
INSULATION MOLD TEST
INSULATION R-VALUES & PROPERTIES
LEED GREEN BUILDING CERTIFICATION
LOG HOME ENERGY EFFICIENCY
MOLD in FOAM INSULATION, RESISTANCE
MOISTURE CONTROL in BUILDINGS
NOISE / SOUND DIAGNOSIS & CURE
RIGID FOAM USE INDOORS
SHEATHING, FOIL FACED - VENTS
SLAB INSULATION, PASSIVE SOLAR
STAINS on & in BUILDINGS, CAUSES & CURES
STRAW BALE CONSTRUCTION
STUCCO WALL METHODS & INSTALLATION
STUCCO OVER FOAM INSULATION
SWEATING (CONDENSATION) on PIPES, TANKS
THERMAL EXPANSION CRACKS in BRICK
THERMAL IMAGING, THERMOGRAPHY
THERMAL MASS in BUILDINGS
THERMAL TRACKING Indicates Heat Loss
TRUSS UPLIFT, ROOF
VAPOR BARRIERS & CONDENSATION in BUILDINGS
VENTILATION in BUILDINGS
WALL CONSTRUCTION BARRIER vs CAVITY
WIND WASHING INSULATION at EAVES
WINTERIZE A BUILDING
Building insulation choices & properties:
This article discusses the properties of various building insulation materials: fiberglass insulation, expanded polystyrene insulation, foil-faced polyisocyanurate insulation, and extruded polystyrene.
Green links show where you are. © Copyright 2014 InspectApedia.com, All Rights Reserved.
Building insulation properties of fiberglass insulation, expanded polystyrene insulation, foil-faced polyisocyanurate insulation, and extruded polystyrene
The table of insulation properties at page top and accompanying text are reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.
"Insulation Options, a few facts to help you choose among foams and fibers":
This article explains the insulating properties and relative costs of common building insulating materials including fiberglass insulation, expanded polystyrene insulation, foil-faced polyisocyanurate insulation, and extruded polystyrene.
The insulation figure of merit, "cost of insulation per square foot R-value, is explained as a means of comparing insulating materials. While the insulation cost data in the original article dates back to November 1983, the concept of using an R-value normalized cost to evaluate insulation is useful today.
For superinsulated buildings the article concludes that a double-stud wall with fiberglass batts provided the greatest insulating value per dollar. However other insulating products may be a better choice depending on other construction details and space limitations.
Our photograph (left) shows an insulation retrofit in a crawl space where icynene foam spray was applied to the crawl space wall and between the floor joists overhead.
The article also discusses the question of air permeability of fiberglass insulation and its impact on the actual insulating value of the material compared with impermeable (to air) foam insulation products. The impact of moisture on the R-value of fiberglass insulation is also discussed (it's low). Fiberglass both gains and loses moisture more rapidly than some other insulating products.
Foil-faced polyisocyanurate insulation such as the Thermax® and Hi-R® brands are discussed - these products give the highest R-value per inch among insulating materials. Also, as we tested in the 1970's, the use of these products combined with a 3/4" air space permits achieving an additional R 2.7 provided that the foil is clean and the gap or air space is uniform.
See POLYISOCYANURATE FOAM INSULATION for details about polyisocyanurate insulation use.
The polystyrene family of insulations are discussed and are recommended particularly for insulation below grade using expanded polystyrene (EPS or beadboard) and extruded polystyrene (such as Styrofoam® - photo at below left, or Foamular®).
Claims (perhaps by competitors) that EPS absorbs water are dismissed as nonsense - the material is used to float docks. The article also discusses the use of polystyrene insulation as a non-structural building sheathing (permitting insulating over building band joists and headers) and as an added control of air infiltration.
Problems reported with use of polystyrene as non-structural sheathing where horizontal wood siding is installed included loose clapboards, cupping or cracked clapboards, and nail pulling due to thermal movement of the foam. The article concludes:
See POLYSTYRENE FOAM INSULATION for details about polystyrene foam board insulation use.
Here we include solar energy, solar heating, solar hot water, and related building energy efficiency improvement articles reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.
Current High-R Building Insulation Products for Super Insulated Buildings
The high-R insulating panel building products currently in most common use are POLYSTYRENE FOAM INSULATION
and POLYISOCYANURATE FOAM INSULATION panels and
also polyurethane spray foam
These materials have a typical R-value of about R-5 to R-6 per inch, though when installed with a radiant surface (that might help) and a 3/4" air gap, the R-value is increased substantially - as we detail below. Fiberglass batts, which are still most-widely used in residential construction, are about R-3 per inch.
Here are some currently-available high-R building insulation products as well as some specialty very high-R insulation materials:
Original Solar Age Magazine Article on High R Insulation Choices
Links to the original article in PDF form immediately below are preceded by the expanded/updated online version of this article above.
Continue reading at INSULATION INSPECTION & IMPROVEMENT or select a topic from the More Reading links shown below.
Suggested citation for this web page
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
No FAQs have been posted for this page. Try the search box below or CONTACT US by email if you cannot find the answer you need at InspectApedia.
Questions & answers or comments about finding, using, diagnosing, repairing, or replacing water pressure gauges on private well systems.
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Search the InspectApedia website
HTML Comment Box is loading comments...
Technical Reviewers & References