Spring has officially sprung, and after a relatively mild winter, it arrived ahead of schedule. If you’re one of the estimated 50 million Americans that suffer from allergies, all the new blossoms and budding trees can be bittersweet. This year has been especially brutal as pollen counts have set all-time records and virtually every surface, indoors and outdoors, is covered in yellow. It is possible, however, to escape the airborne impurities brought on naturally or otherwise.

Insulated Concrete Form (ICF) structures have become synonymous with energy-efficiency due to their solid, nearly airtight envelope. Another noteworthy benefit, though, that comes with such an impervious design is their ability to block outside contaminants. Because concrete doesn’t breath like its lower-performing, wood-framed counterpart, it blocks not only heat and cold from penetrating its walls, but also pollen, dust and other airborne pollutants. The building envelope is extremely tight in an ICF structure, therefore, it is often recommended that energy recovery ventilators (ERVs) be installed to bring in fresh air and still maintain the air quality. ERVs use energy from the stale, outgoing air to precondition the ventilated, incoming air in HVAC units, allowing for control over the air exchanged. The humidity level is also controlled through ERVs in combination with the ICF structure, preventing mold and mildew. These two common indoor irritants often render indoor air quality much more harmful than being outside, regardless of the time of year.  The result is a year-round clean, healthy living environment!

Tuesday, February 21, 2012 – A Better House Inc., Middle Tennessee’s most-established green builder and distributor, will be breaking ground this month on the MDHA venture, the Woods at Monticello, a low-energy, affordable-housing development in North Nashville.  This will mark the first of four homes, now available for pre-sale, to be constructed by the company, with a completion date scheduled tentatively in the spring.  Qualifying families of four must earn a combined annual income of $52,950 or less.

Slab foundations and crawl spaces are the two most common options when determining a foundation as they seem to be the most cost-effective. But, are they really?  Depending on location and budget, a basement is also another option from which homebuilders have to choose.

Slab foundations are the least expensive as they require minimal digging, which, in turn, means less in labor and materials. The floors in homes built on this solid foundation are also much sturdier than their wooden counterparts. If walking on concrete is a concern, one might consider a wooden sub-floor. to provide a layer for shock absorption.  In slab foundations, all plumbing pipes and electrical wiring is embedded in the slab, which acts as an insulator and protects them from the elements

Some may argue that the floor on a slab is colder, however, if a waterproofing barrier is placed correctly under the slab, it provides a layer of air between the slab and the ground which insulates it and keeps it room temperature.  This is especially true when building with ICFs (insulated concrete forms) as the slab is poured inside the concrete walls, further insulating the floor from the elements.

Crawl spaces, usually not over four feet in height, are typically soil, which makes a vapor barrier absolutely crucial to prevent moisture from seeping in and promoting mold growth. When building an energy efficient house and trying to create a tight building envelope, a crawl space may not be the best option.  In order to stop air infiltration, the crawl space must also be insulated, otherwise the damp, unfiltered air is pulled into the house from the HVAC return and will seep in through the floors.  This additional  insulation means an increase in cost as well.

Additional exterior materials will also be needed when utilizing a crawl space (brick, stucco, siding) as well as added materials for building the walls on which the house resides.  If thinking about a crawl space, it would be wise to pay a bit more and install a full basement.  The increase in cost from a crawl space is not significantly more, but it will provide a significant increase in square footage which translates into additional living space and increased resale value.