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ACOUSTICAL SEALANT CHOICES
AIR BYPASS LEAKS
AIR LEAK DETECTION TOOLS
AIR LEAK MINIMIZATION
AIR LEAK SEALING PROCEDURE
AIR POLLUTANTS, COMMON INDOOR
AIR TEST FOR MOLD: ACCURACY
AIR TEST SAMPLING CASSETTE STUDY
ALLERGEN TESTS for buildings
ALLERGENS in BUILDINGS, RECOGNIZING
ALLERGY & MOLD IAQ PRODUCTS
ALLERGY TESTS for PEOPLE
ALLERGY TEST ACCURACY
ANIMAL ALLERGENS / PET DANDER
ANIMAL ENTRY POINTS in BUILDINGS
ANIMAL or URINE ODOR SOURCE DETECTION
ASBESTOS IDENTIFICATION IN BUILDINGS
ROOF ICE DAM LEAKS
BASEMENT CEILING VAPOR BARRIER
BASEMENT HEAT LOSS
BASEMENT LEAKS, INSPECT FOR
BEST CONSTRUCTION PRACTICES GUIDE
BUILDING NOISE DIAGNOSIS & CURE
CATHEDRAL CEILING INSULATION
CATHEDRAL CEILING VENTILATION
CEILING FINISHES INTERIOR
CEILINGS, DROP or SUSPENDED PANEL
CEILINGS & WALLS, PLASTER TYPES
CEILINGS, PLASTER, LOOSE HAZARDS
COMBUSTION AIR for TIGHT BUILDINGS
COOLING LOAD REDUCTION by ROOF VENTS
CONDENSATION or SWEATING PIPES, TANKS
CONDENSATION on WINDOWS & SKYLIGHTS
DECK & PORCH CONSTRUCTION
DEW POINT CALCULATION for WALLS
DEW POINT TABLE - CONDENSATION POINT GUIDE
DIRECTORY of MOLD / ENVIRONMENTAL EXPERTS
DIRT FLOOR MOLD CONTAMINATION
DISINFECTANTS & SANITIZERS, SOURCES
DISINFECTING BUILDINGS with BLEACH
DRYWALL MOLD TESTING
EFFLORESCENCE, Salts & White / Brown Deposits
ENERGY SAVINGS in BUILDINGS
ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY
FIBERGLASS INSULATION MOLD
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOOD DAMAGED FOUNDATIONS
FLOOD VENTS & FLOOD PORTS
FLOODS IN BUILDINGS-mold
FLOOR & SUBFLOOR MOLD, HIDDEN
FLOOR TYPES & DEFECTS
FLOOR TILE HISTORY & INGREDIENTS
FOOTING & FOUNDATION DRAINS
FOUNDATION BULGE or LEAN MEASUREMENTS
FOUNDATION CRACKS & DAMAGE GUIDE
FOUNDATION REPAIR METHODS
FRAMING DAMAGE, INSPECTION, REPAIR
FRAMING DETAILS for BETTER INSULATION
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
HEAT LOSS RATE CALCULATIONS
HEAT LOSS in BUILDINGS
HEAT LOSS DETECTION TOOLS
HEAT LOSS INDICATORS
HEAT LOSS PREVENTION PRIORITIES
HEAT LOSS R U & K VALUE CALCULATION
HEAT TAPES & CABLES on Roofs for Ice Dams
HEATING COST SAVINGS METHODS
HOUSEWRAP AIR & VAPOR BARRIERS
HOUSE DOCTOR, how-to be
HUMIDITY LEVEL TARGET
ROOF ICE DAM LEAKS
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INDOOR AIR QUALITY IMPROVEMENT GUIDE
INDOOR HOUSE DUST & DEBRIS
INSECT INFESTATION / DAMAGE
Insulation Air & Heat Leaks
INSULATION FACT SHEET- DOE
INSULATION for GREENHOUSE or SOLARIUM
INSULATION IDENTIFICATION GUIDE
INSULATION INSPECTION & IMPROVEMENT
INSULATION LOCATION - WHERE TO PUT IT
INSULATION LOCATION for BRICK VENEER WALLS
INSULATION LOCATION for CAPES, CRAWLSPACES
INSULATION LOCATION for CATHEDRAL CEILINGS
INSULATION LOCATION for GREENHOUSE or SOLARIUM
INSULATION R-Values & Properties
MOISTURE CONTROL in BUILDINGS
MOLD INFORMATION CENTER
MOLD in FOAM INSULATION, RESISTANCE
NOISE / SOUND DIAGNOSIS & CURE
ODORS GASES SMELLS, DIAGNOSIS & CURE
PAINT FALURE, DIAGNOSIS, CURE, PREVENTION
ROOF VENTILATION SPECIFICATIONS
ROT RESISTANT LUMBER
ROT, TIMBER FRAME
ROT, TIMBER ASSESSMENT
SAFETY HAZARDS & INSPECTIONS
SLAB CRACK EVALUATION
SOUND CONTROL in BUILDINGS
SPLITS & CRACKS in STRUCTURAL WOOD BEAMS
STAIN & BIODETERIORATION AGENT CATALOG
STAINS on & in BUILDINGS, CAUSES & CURES
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
STAIN DIAGNOSIS on ROOFS
STAIN DIAGNOSIS on STONE
STAINS & FINISHES, INTERIOR
STAINS on INDOOR SURFACES: PHOTO GUIDE
STAIRS, RAILINGS, LANDINGS, RAMPS
STAIR FALL & TRIP HAZARDS
SEPTIC SYSTEM PUMPS
Sump Pump Discharge
Sump Pump Inspection
Sump Pump Types
Submersible Sump Pump Guide
Pedestal Type Sump Pump Guide
Battery Backup Sump Pump Choices
Water Powered Sump Pump Guide
Sump Pump Single vs Duplex
SWEATING (CONDENSATION) on PIPES, TANKS
Thermal Expansion Cracking of Brick
THERMAL EXPANSION of HOT WATER
THERMAL EXPANSION of MATERIALS
THERMAL IMAGING, THERMOGRAPHY
THERMAL IMAGING MOLD SCANS
THERMAL MASS in BUILDINGS
THERMAL TRACKING & HEAT LOSS
TRIM, INTERIOR INSTALLATION
TRAPPED MOLD BETWEEN WOOD SURFACES
TRUSS UPLIFT, ROOF
TRUSSES, Floor & Roof
VAPOR BARRIERS & CONDENSATION in buildings
VENTILATION in BUILDINGS
WALL FINISHES INTERIOR
WALL CONSTRUCTION BARRIER vs CAVITY
WATER ENTRY in buildings
WIND WASHING INSULATION At EAVES
WINDOWS & DOORS
WINTERIZE A BUILDING
WOOD Burning Heaters Fireplaces Stoves
WOOD FLOOR DAMAGE
Crawl space insulation improvements - retroffitng insulation into the crawl area: this article describes several alternative processes for adding crawl space insulation and the use of spray foam insulation in crawl areas. We include photos that compare spray foam insulation with cut-and-paste foam board insulation. Our page top photo shows why you would want to remove old fiberglass insulation, then clean, and properly insulate an existing crawl area, but the advice below pertains to new construction as well.
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A variety of foam building insulation products are marketed for insulating crawl areas. See our discussion of the properties of different insulation materials at INSULATION INSPECTION & IMPROVEMENT and be sure to review these articles:
Using Polyurethane Foam or Icynene® Insulation for Crawl Space Insulation Retrofits
At Icynene Foam Spray Insulation we discussed the properties of Icynene® foam insulation (and similar products). This foam is a spray-in-place product, injected through openings, or pour-in expanding-foam insulation product. Other water borne foam spray insulation products, including some latex-foams, are available.
Our photo (left) illustrates the author testing for air leaks at an apparent void in foam insulation sprayed in a tight crawl space.
Where access is very restricted it can be difficult to spray any foam in a smooth, uniform, and airtight pattern. Our next photo (below left) illustrates a mixed-media insulation retrofit in a crawl area.
At URETHANE FOAM Deterioration, Outgassing we discussed some historic concerns surrounding polyurethane foam insulation, including the water resistance of open-celled spray foams, outgassing, and insect resistance.
But there are modern spray polyurethane products that are closed-cell insulation suitable for use in damp locations and that may perform well in a crawl space, avoiding the issues we discussed above as well as the issue of mold formation in fiberglass insulation. (See Mold in Fiberglass Insulation and Mold in Foam Insulation for details about mold problems in building insulation.)
See How to Make a Sure Distinction Among UFFI, Icynene, and Latex Foam Insulations for more detail on the identification of these individual foam insulation products in the field
Here is what the U.S. Department of Energy says about polyurethane insulation in buildings - (the US DOE comments are consistent with our text above):
Sprayed-Foam Polyurethane Insulation
Rigid Polyurethane Foam Board Insulation for New & Retrofit Insulation Jobs
Also notice the trouble we had retrofitting solid foam cut boards around the waste pipe when working in a tight crawl area.
You might ask why we didn't cut a perfect-fitting rounded or notched board section to fit on either side of the waste pipe (photo at left).
Try hauling a bundle of 2-inch foam board slabs down into a tight crawl area (photo below left) that requires contortions just to enter or exit the space. Add working alone.
And ask yourself how many trips you would be willing to make crawling in to measure, out to cut, in to test-fit, out to adjust each cut.
You can see from the photo (below left) that this was a tight area - putting down plastic not only helped the installer (me) move around in the crawl area, it helps keep the crawl area dry.
A better approach may be to use the cleat and nail support system we show here, but to make a final pass with a few cans of spray foam or spray fireblock foam insulation to complete the job.
Readers interested in the mold resistance properties of foam insulation should see Icynene Foam Spray Insulation.
Insect Attack on Foam Insulated Foundations
Wood destroying insect effects of foam insulation: foam insulation is not an insect barrier; while these materials do not provide food for termites, they are easily penetrated by termites or carpenter ants (as are other insulating materials). For this reason our opinion is that it is bad design to bring foundation insulating foam panels up into contact with building wood framing materials unless an approved insect barrier has also been installed.
What can we do to improve the insect resistance of buildings where solid foam board or foam spray foundation insulation are being applied? Having read our recommendations and warnings at Insects & Foam Insulation, reader S. Frank asked if insulating a crawl space with spray foam would create a risk of insect attack on the building.
The insect path formed by foam, such as foam board on the outside of a foundation and brought up in contact with wood framing, can be a risk to a building, especially if wood destroying insects are common in the area and if other factors such as water conducive to insect attack are present. Insects don't "eat" the foam but it can provide a protected pathway up from soil into wood structural elements.
Otherwise you should consult with a local pest control professional to discuss whether or not a pre-treatment or installation of termite shields are necessary. Also see TERMITE SHIELDS vs TERMITICIDE.
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