STEPS TO A SUPERIOR ICF WALL SYSTEM
Building with insulated concrete forms is an efficient process that is far less labor intensive than most traditional construction methods. The lightweight forms assemble quickly to form a complete exterior wall system that's ready for interior and exterior finishes. And there are no limits on the height, size or shape of the structure.
1. Vertical rebar is set around the perimeter of the foundation when it’s poured.
2. The forms are assembled one run at a time and horizontal rebar is placed per engineering specifications (Logix ICF forms may be white or gray – depending on the form being used).
3. Several courses are assembled to the proper wall height, and window and door openings are framed in. Any necessary mechanical, plumbing or other penetrations are sleeved through the wall prior to placing the concrete.
4. Once the walls are up, vertical rebar is placed, any cut seams are blocked and the wall bracing is installed to ensure the walls remain secure and plumb during the concrete pump.
5. The wall cavity is pumped full of concrete; the walls are constantly being vibrated and string lines are checked to ensure concrete is consolidated and walls are straight; truss straps and j-bolts are wet set in the concrete wall (meaning your roof trusses are securely anchored into the ICF wall – they’re not going anywhere).
6. The braces are removed and the forms obviously stay in place to serve as interior/exterior wall insulation.
7. Electrical wiring is installed quickly and easily using a hot knife to cut penetrations and channels in the foam.
Ready for finishes!
8. Drywall is installed on the interior walls by fastening to the webs embedded in the foam every 8” on center (twice as many fastening points as traditional framing). Siding is attached to the exterior using the same webbing system. No furring strips or additional preparation is necessary for interior or exterior applications. An ICF wall is ready for brick, stucco, vinyl, Hardie board or any other exterior finish to be applied directly to the wall system.
THE SAVINGS ARE REAL…..AND MEASURABLE!
So, you’re asking, what is this “superior” house going to cost me? Well, the answer may surprise you. On average, the cost to build an ICF home only results in a 5% increase in up-front construction costs. This makes wading through all of the misinformation put forth by some in the building community who have never built an ICF home and are not familiar with all aspects of this specialized construction process very important. An experienced ICF builder will know that the HVAC system in an ICF structure can be downsized, there is no need for wall insulation, vapor barriers, furring strips or many other features
required for a traditional wood-framed or concrete block wall
system (not to mention the potential for reduced labor costs). An
experienced ICF builder will also recommend other energy saving
features to be included in your ICF home, such as spray foam
insulation to the roof deck to completely “seal the envelope” and
an on-demand water heating system. The biggest impact of all
comes in the long-term savings from energy bills that are cut in half and the significantly reduced insurance premiums that accumulate over the entire time you occupy the home, leaving more money in your pocket each month. The chart below (partially courtesy of LOGIX® Insulated Concrete Forms) effectively communicates this:
WHAT IS “ICF”?
All of the homes that we build at Praesidium Homes are constructed
using an advanced technology commonly known as “ICF construction”.
Our experienced team has been building ICF homes and structures
in the Tallahassee area since 2004. Insulated concrete forms (or ICF’s)
are interlocking blocks consisting of 2 panels of expanded polystyrene (looks like styrofoam – but it’s not – it’s far superior) connected by a series of polypropylene webs. The forms are stacked up (much like giant Lego® blocks which they are commonly compared to), then reinforced with vertical and horizontal rebar. The cavity is then pumped full of concrete to form the most durable, energy-efficient, safe and comfortable wall system possible.
Unlike traditional wood-framed wall systems, ICF wall systems prevent costly energy loss due to the superior R-factor of the continuous foam insulation. They also provide an unmatched wind rating due to the strength of the concrete, up to a 4-hour fire rating, and incredible sound resistance which all equate to significantly lower energy bills and lower insurance premiums. As an added bonus, the standard ICF wall system is naturally termite resistant because there is no nutrition source for these pests inside of a concrete wall system. Some ICF forms go the extra mile by including an optional termite preventative for added protection.
Mold and mildew are also no match for an ICF wall because there is no space inside the wall system to foster their growth. This means you can rest assured that the air quality inside of this air-tight home is far superior to that of traditionally built homes. As you can probably imagine, since the outside temperature, pests, wind and moisture can’t penetrate these walls, neither does sound!
Another innate benefit of ICF's is found in the window sills. After finishes are applied inside and out, typical final wall thickness is just over 12". This means that the depth of window and door surrounds are substantially wider resulting in deep window sills—a nice feature for homeowners.
Additionally, the EPS foam and concrete in the walls, which are partially made from recycled materials, are non-toxic and do not off-gas, reducing green house gas emissions by as much as 1/3 that of a wood-framed home. They also significantly reduce the amount of wood and other precious natural resources used in the construction of the home. There is no other construction method available today that provides all of the cost saving features, safety, quietness, comfort and peace of mind that an ICF wall system provides – all while reducing the impact on our environment. That’s more than just a “green home”. That’s a far superior Praesidum Home!
BENEFITS OF ICF
MOLD & MILDEW RESISTANT
SAFE, QUIET & COMFORTABLE
CLEANER INDOOR AIR QUALITY
A LITTLE HISTORY
The history of ICFs dates back to after World War II, when blocks of treated wood fibers held together by cement were used in Switzerland. In the 1940s and 1950s, chemical companies developed plastic foams, which by the 1960s allowed a Canadian inventor to develop a foam block that resembles today’s typical ICFs, where the forms were used for basement construction. In the 1980s and 1990s, some American companies got involved in the technology, manufacturing blocks and panels or planks.
ICF systems were initially very costly to construct, but as word of ICFs grew and innovations reduced manufacturing and installation costs, builders began using the forms for not just high-end custom homes, but also mid-price-range homes.
The above figures are estimates based on actual utility and insurance bills provided by customers. Construction, mortgage, energy and insurance costs may vary depending on style, design and location of home.
As we move towards buildings that are "net-zero" - meaning they sell energy back to the grid instead of buying it, an ICF home is the place to start. The highly energy-efficient shell combined with energy producing solar panels make it possible. Ask us how!