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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 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 location & placement:
This article describes the optimum placement of building insulation for various building designs, problem spots, and hard-to-insulate or hard-to-ventilate building spaces.
We include Cape-style building roof & attic knee wall insulation advice or for homes with no basement, crawl space insulation placement advice, & basement insulation advice
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Next the article discusses the best placement for insulation in crawl spaces. We explain that the location of building insulation is as important as its quantity. Sketch at page top and accompanying text are reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.
Insulation Advice for Cape Style Homes
In the Cape-style under-roof insulation and ventilation plan suggested in this article and illustrated at page top, insulation location shown as option (B) at the right side of the sketch is the preferred insulation placement for a Cape-Cod home because
But in any under-roof insulation scheme beware of these common Cape Cod insulation problems:
Insulation Advice for Full Basements
Mr. Bliss prefers insulation on the basement interior for the same reason that apply to crawl spaces, including avoiding frozen pipes.
He suggests using a section of rigid foam insulation to separate off hard-to-insulate basement locations such as steel bulkhead basement walkout doors.
Our photograph (left) shows styrofoam insulating foam board used on the inside of a basement foundation wall.
We prefer to use solid foam insulation in any below-grade location that is at risk of period high moisture, because our field and lab work have shown up frequent hidden toxic mold reservoirs in fiberglass insulation that has been used in those locations.
See MOLD in FIBERGLASS INSULATION for details.
Frost damage at basement exits to the exterior is discussed
Insulation Advice for Crawl Spaces
Crawlspaces are common in homes in the southeastern U.S. as well as in some west coast cities such as Los Angeles. Crawl spaces are a breeding ground for wood decay and mold because they combine a mixture of moisture, wood, and warmth. As Mr. Bliss points out in part 1 of the article above, less insulation will be required to insulate the crawl space walls and building rim joist than to insulate under the floors.
In cold climates insulating the floor may also require extra insulation on plumbing to protect it from freezing in the colder crawl area. In warm weather insulating the floor loses the cooling effect of its location over the cooler ground surface.
Additional links to articles on good crawl space design and solving crawl space problems are provided below.
Insulation Advice for Mudrooms
In the articles above, the author suggests that attached spaces such as mudrooms that get frequent use should be inside the building's thermal envelope. If a mudroom is excluded from the building envelope of conditioned space (heated, dried, or seasonally cooled and dehumidified), there is an increased risk of mold since the rooms receive household moisture but little heat.
If the mudroom or airlock entry space is used rarely, such as an enclosed porch, you can go either way - insulating it or not, but if an attached room on a house is left unheated, be sure that it is also isolated from the home's moisture by proper placement of vapor barriers.
Insulation Advice for Sunspaces
Mr. Bliss points out that sunspaces are always insulated from the outdoors, but asks "... should they be insulated from the house?"
In climates that have frequent periods of cold and cloudy weather, it's a good idea to insulate and seal between the sunspace and the house - assuming that you are not trying to keep heat in the sunspace to keep plants alive through cold weather. If plants are being maintained in a sunspace you may need to heat that area as well.
Insulation between the house and the sunspace can be less than that in other house walls facing directly outdoors because of the buffering effect of the sunspace. But the air space between the sunspace and the house should be tight to keep greenhouse moisture from entering and causing mold or other problems in the main building.
In sunny climates that can keep the sunspace mass warm all winter, uninsulated walls between the sunspace and the main building are fine. Night insulation is a good idea for these sunspaces since the sunspace glass is part of the thermal envelope.
See SLAB INSULATION, PASSIVE SOLAR - slab insulation & vapor barrier placement in heated floor slabs.
Insulation Tips for Stairwells and Other Interior Discontinuities or "Bumps" in a House
Good planning during construction can avoid these problems by making sure that insulation and vapor barriers are properly placed. In retrofits to older buildings it's not so easy, Mr. Bliss notes.
For insulation retrofit on older buildings don't forget to watch for, evaluate, and if appropriate open and insulate these areas.
A common example that we see on older homes is the failure to insulate below attic stairs whose ceiling is exposed to the otherwise heated and insulated main area of the home.
In our attic stairwell photo (left) the house exterior wall and the area underneath the stairs themselves were uninsulated, leaking heat out of this home.
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.
What about Insect Damage or Mold Contamination in Insulation?
Readers interested in the mold resistance properties of foam insulation should
Original Solar Age Magazine Article on Building Insulation for Various Building Designs
"Where to insulate: the location of building insulation is as important as its quantity" - links to the original article in PDF form immediately below are followed by an expanded/updated online version of this article.
Continue reading at BASEMENT WALKOUTS & COVERS or select a topic from the More Reading links shown below.
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