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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 Cracking of 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
Slab insulation placement guide: this article discusses the question of insulating under a basement floor slab, and just where is the optimum placement of basement insulation.
This article explains that the location of building insulation is as important as its quantity. Sketch at page top is courtesy of Carson Dunlop Associates.
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The accompanying text is adapted and expanded from the original article with permission from Solar Age Magazine - editor Steven Bliss.
Is it necessary to insulate under a slab in a superinsulated house? I assume an uninsulated slab would help cool the house in summer. -- William Lee, Cave Creerk AZ
Experts [in 1985] did not agree as to whether or how much to insulated below a slab. It is most important to insulated the perimeter of a slab down to the bottom of the footing.
Second most important [to insulating the slab perimeter down below the frost line] is to insulate under the first few feet around the edge of the slab.
In [moderate] climates where cooling as well as heating is an issue, it may be best to insulate only the perimeter and leave the underslab uninsulated, as you suggested, for cooling.
Full insulation is indeed recommended under the slab in some situations.
These include radiant heat delivery
or passive solar storage
Also, if wood flooring or carpeting isn't planned, underslab insulations will make the floor feel warmer to bare feet.
The material of choice for insulating a slab would be high density, closed-cell rigid foam board insulation, such as extruded polystyrene.
Thermally break the interior finish of the basement floor from the concrete (e.g. with wood or solid foam board) to increase comfort and to control condensation if that's a problem in your area during summer months.
If you are installing a radiant heat basement floor system, insulation under the floor slab and the location of the heating tubing are critical - see RADIANT HEAT Floor Mistakes to Avoid.
The link to the original Q&A article in PDF form immediately below is followed by an expanded/updated online version of this article.
Continue reading at INSULATION LOCATION for PASSIVE SOLAR FLOOR SLAB or select a topic from the More Reading links shown below.
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