Quote:
Originally Posted by AC_Hacker
Less? How much less?
In this thread, I keep hearing words like "negligible" and "less".
When you say less, do you mean 1% less, do you mean 95% less?
When you say "less" exactly how much less?
That's one thing I really respect about the Passive House design approach. They didn't disregard 'negligible' losses or 'insignificant' gains... they don't throw away 'less'.
And you know what? All these disregardable quantities that conventional thinking brushes aside, have added up to a revolution in thinking, and a whole new approach in house construction.
-AC |
The correct answer here is:
Not everyone wants to invest the time, labor, and money to do the best job possible. There is usually a point where the return on investment diminishes beyond design goals or a target is hit (or missed). A "Take no prisoners" approach, such as the passive house standards employ, is a noble cause (which I and many others here subscribe to) that many of intermediate skill level doubt they can accomplish.
This is especially true in the renovation/remodel/retrofit arena. Many homeowners completely neglect energy efficient building methods when planning DIY projects. Those that consider air sealing and insulating weigh the cost vs. benefit aspect heavily. In the hydronic heating realm, the extra money is not always spent in the right place with respect to the overall efficiency of the system. Given a choice, the average DIY installer will oversize the capacity of the system to cover 99.9% of the existing heat load rather than to insulate enough that a smaller capacity system would do the same job.
Other well-intending home improvers are swayed by the lofty claims of previously mentioned manufacturers and integrate these products into their design, relying on these high-performance values to "pull their weight". After commissioning and operating the system for some time, the DIY'er realizes the system is not as efficient as it should be on paper and begins to hunt for answers why. More often than not, the individual must bring in third parties to get a grip on the situation and dispel the mythology. By then, most, if not all of the budget has been spent. The remediation is then either done at great pain, or not done at great pain.
Anyone who has much experience in building projects knows that you nearly always experience problems and run over budget. One day you're golden, the next it's doom and gloom. It takes a good amount of diligence and patience to stay on track. It's much easier to delete a step or three along the way rather than to dig in and do it right the first time.