High Perfomance Homes

"The R-Value Myth"

Performance predictions using heat transfer calculations based on tested and published R-values alone do not accurately predict real-world performance. R-Value is a term given to the property of any material to "resist" the conduction of heat. R-Value as a property is legitimate. The functional design of the laboratory determination of this property, relative to commercial insulation materials, is flawed at a fundamental level - yielding what can be called the R-Value myth. This flaw forces the engineering community, bound to adhere to the scientific formulas dictated by their governing body (ASHRAE), to calculate heat loads using the "myth" that this R-Value property of various insulation materials derived by flawed test methods can accurately predict the performance of the insulation material in real life.   In addition, it has allowed the use of the term R-value to allow many builders the ability to overstate the benefits of certain insulation packages to the buying public.

Let's look at two of the "test criteria" used in the laboratories to determine R-value. The first criteria relates to "standard temperature". This stipulates that the test be conducted at a constant temperature of 75-degrees Fahrenheit. Does it seem odd that a test to determine the performance values for insulation material for HVAC equipment would be designed around a 75-degree temperature? Who uses heat or cooling when it's 75 degrees? It isn't surprising that fiberglass performs well at 75-degrees. However, the efficacy of fiberglass decreases in efficiency at hotter and cooler temperatures while foam both performs very well at hotter and cooler temperatures. Now do you see why we're suspicious of R-Values as a rule of thumb?

Secondly, the "test criteria" requires that R-value testing not start until the materials reach "steady state". Steady state occurs when a material is exposed to a heat source on one side and allowed to become thermally saturated so that for every single unit of heat entering on one side of the material a single unit of heat exits the opposite side. This seems very scientific. It appears logical, but it misses a single important issue relevant to predicting real world performance: The amount of time it takes to reach steady state.

We begin by having each of our homes engineered for its type of construction, orientation on the lot, and size. The next step is calculating the HVAC requirements for each structure including zoning and sizing of all HVAC equipment and room by room CFM load requirements. Air infiltration is addressed based on the type of construction used. . We require caulking every place air can infiltrate: multiple joints, window and door frames, sill plates, plumbing and electrical penetrations, etc

The largest factors contributing to discomfort in the home are the humidity levels in the summer and inconsistent hot and cold spots throughout the structure. We solve this by correctly matching and sizing your HVAC system to an airtight home to maintain a guaranteed relative humidity level between 35% and 50%

(when the HVAC system is running). We can virtually eliminate those undesirable hot and cold spots by properly positioning your home's duct work while accounting for the number and type of windows and the physical position of your home and its surrounding environment. It is critical to have the HVAC system properly designed to maintain ideal humidity levels or you run the risk of experiencing a home that is too dry (resulting in baking the paint and drying the caulk), or too wet using stick framing with a spray foam insulation application, property owners will achieve very favorable results and it is a very attractive alternative.

The spray foam insulation will be applied using "open cell” formulations.  These products are applied by spraying the backside of the exterior walls before the sheetrock goes up, but after all the plumbing, electrical wiring, etc. It goes on as a heated liquid and then quickly expands, completely filling every open space, around every pipe, electrical outlet or light switch, and windows. The spray foam cures within seconds providing temperature, sound and condensation control in one fast application. It simultaneously insulates and creates an air and sound barrier. Good caulking techniques are added and the result is a virtually air-tight structure and you can begin to realize the benefits of "Ultra Energy-Efficient" construction. We then caulk every place air can infiltrate: multiple joints, window and door frames, sill plates, plumbing and electrical penetrations, etc

Designed by Tyler New Inc.