Energy Wise Home Builders

Energy Wise Home Builders, Co

Home • Floor Plans • Contact • Energy-Smart Home • Home Envelope • Foundation • Framing

Heating & Cooling • Windows and Doors • Roof • Ventilation • Appliances • Credits

The Home Envelope

The exterior of your home is also called the "envelope" or shell. The insulation, outer walls, ceiling, doors, windows, and floors all work together to control airflow in and out of the structure, repel moisture, and prevent heat from being lost or gained inside your home.

Since the early 1970's, sealing the building envelope has been recognized as an important component in both energy efficiency and structural durability. In a poorly sealed home, heated air flows out through cracks and seams in the building envelope—ceilings, walls, windows, doors, and other penetrations around the building exterior. Moisture, carried into the wall and ceiling cavities by air movement or by vapor diffusion, may damage building insulation and structural materials.

Your home's thermal envelope is the outer protection that shields the living space from the outdoors. The tighter the envelope or seal, the more efficiently your home will operate and the greater your energy savings. The overall design, building techniques and quality of construction of your home will determine how tightly it is sealed from the elements.

An airtight building envelope has better energy efficiency, fewer hidden moisture problems, and it allows the occupants to have more control of the indoor air through the use of mechanical ventilation equipment. With airtight construction, the living space is effectively isolated from the insulation and the outdoors. The construction techniques employed by Energy Wise Home Builders, Co. creates an envelope virtually impermeable to air. Used in conjunction with caulking, gaskets, airtight electrical boxes, superior window and door installations that are able to withstand the air pressure loads that act on them we achieve practically an airtight structure.

In order to determine the actual tightness of the completed house envelope, a blower door depressurization test is performed. A flow rate of 99 cfm (equivalent to 0.45 air changes per hour) is measured at a 50 Pascal depressurization. From a practical standpoint, the structure is almost airtight, so the occupants will have maximum control over the quality of the air in the house through judicious use of the ventilation/filtration system

A high-performance envelope helps maintain a consistent temperature even under extremely hot or cold conditions. The goal of Energy Wise Home Builders, Co is to improve the home envelope and thus make homes more comfortable, hurricane strong and truly energy efficient.

About Insulation

Thermal insulation is assigned an R-value based on its ability to resist heat — the higher the number, the greater the material’s ability to keep your home cooler in the summer and warmer in the winter.

Insulation is designed to resist heat flow - that is, if it is hot outside, insulation greatly reduces the amount of heat you can feel inside a house. Or, if it is cold outside, insulation helps keep the heat inside the house. The better the insulation, the better the envelope of the home.

Insulation works best when air is not moving through or around it. Therefore, it is very important that air leaks be sealed to ensure that you get the full performance out of any insulation that is installed. With our structurally insulated panels there are no breaks in the insulation. They provide a solid wall completely enveloping your house.

The individual air sealing practices of the contractors or insulators have a larger impact on air leakage than the insulation products themselves. Minimizing air infiltration is dependent on the sealant package, not the insulation.

Some fiber glass loose-fill insulation may settle over time. It may lose about 20% of its R-value when it settles. In general, insulation will lose R-value when wet. Over time many traditional "stick built" houses loose up to 50% of their insulation abilities from the deterioration of the moisture barrier, caulking, settlement cracks and the effects of this leakage and moisture on the insulation itself.

Air Infiltration

Air infiltration is the uncontrolled leakage of air into and out of a home. It is driven by wind, temperature differences, or HVAC appliance-induced pressures.

Air leakage
This occurs when air enters or leaves the home through gaps between framing materials, plumbing and wiring holes, or around improperly installed doors and windows.

Attic insulation
Living spaces are separated from attics and garages by insulated barriers.

Cellulose Insulation

Cellulose insulation is generally made up of about 80% recycled newspapers and 20% fire-retardant chemicals. On the surface, cellulose insulation may appear to be the more environmentally acceptable insulation choice as it is made from shredded newspaper. However, it takes three times more cellulose material by weight than fiber glass to insulate a typical home. In addition, an average 1200 square foot attic insulated to R-38 with cellulose insulation would introduce 300 pounds of fire retardant chemicals into the home.

Certain chemicals routinely applied as a fire retardant to most cellulose insulation (particularly the sulfates) can cause the corrosion of pipes and wires under some conditions.

Tests conducted by the California Bureau of Home Furnishings and Thermal Insulation have demonstrated that some cellulose samples failed the standard fire safety test only six months after installation. Additionally, smoldering combustion and re-ignition problems are concerns with cellulose insulation should a fire start. Even properly treated cellulose insulations will burn at about 450°F. That's the surface temperature of a 75watt light bulb. In fact, cellulose insulation is regulated as a recognized fire hazard by the Consumer Product Safety Council (CPSC).

If soaked, from water leaks, flooding, roof leaks, cellulose will "mat" down and thermal performance can be permanently reduced. Assuming existing cellulose does dry after becoming wet, there is a concern that the fire retardant chemicals may "wash away" leaving insulation materials insufficiently protected.

Questions about the health and safety aspects of cellulose insulation persist in the building industry because comprehensive medical scientific testing of the products has never been conducted. Repeated requests by union and contractor groups that such testing be undertaken have been ignored. The long-term effects of exposure to homeowners from the chemically treated cellulose installation filling the cavities of theirs walls and the attic of their home are unknown.

Fiberglass Insulation

Fiberglass is naturally noncombustible and remains so for the life of the product. By itself it requires no additional fire-retardant chemical treatments. But most Kraft and foil facings available on fiber glass insulation are themselves combustible. Products with such facings are intended for non-exposed applications and should not be left exposed.

Sound Control

In comparison testing, representative 2 x 4 and 2 x 6 wood stud and metal stud walls demonstrated equivalent or slightly better performance for fiber glass over cellulose when the cavities were completely filled. The SIP walls have more than double the performance for sound control when compared to either fiberglass or cellulose insulation.

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Home • Floor Plans • Contact • Energy-Smart Home • Home Envelope • Foundation • Framing Heating & Cooling • Windows and Doors • Roof • Ventilation • Appliances • Credits

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