5 Important Things to Remember for an ICF Home Plan Conversion
The building industry has seen a relatively recent trend of architects, designers, and homeowners moving away from energy consumptive forms of construction and the implementation of more sustainable, less expensive construction methods. One example of this is the use of insulated concrete forms (ICFs) in place of traditional construction methods.
The use of ICFs in construction projects is becoming increasingly popular due to the wide range of benefits they offer. However, the majority “off-the-shelf” house plans are typically prepared for traditional wood frame construction, meaning the plans need to be altered slightly to accommodate the new construction method.
Plan conversions for ICFs can be relatively straightforward, and almost any type of building plan can be easily modified by a reputable designer or architect.
1. What plans can be converted to ICF?
Plan designs for any building type can be designed or converted to ICFs if you follow a few basic guidelines.
The original designer of any building plan maintains rights over the drawing and should be consulted prior to any design changes. This is important if you work with a different architect and want to avoid any potential copyright issues.
There are also hundreds of plans for ICF construction available online for homeowners to choose from. Whichever route the homeowner chooses for converting their design, the main difference in a new ICF plan involves expansion of the building’s footprint.
“Clients should have an idea of what system they want to use before going to an architect," says Al Meek, director of design for Bloodgood, Sharp and Buster, "because he will need to include product-specific details in the converted plan. This means they must find an architect who has experience with the particular system.”
It’s beneficial to find an architect with experience with flat wall ICF products and detailing. ICF manufacturers have product and application specific detail libraries, BIM details and prescriptive engineering tables to assist the designer.
2. How long does the construction project take?
The conversion process and a successful build depends on the project’s architect or designer and their understanding of ICF construction. A designer who has familiarity with ICF construction will help to ensure that the process runs more quickly.
One of the main benefits of ICF construction is a quicker timeline for completion than traditional wood frame construction. Builders are able to pour large sections of concrete at once, so construction is completed in a similar timeline as other homes — sometimes even a little faster. ICFs allow the builders to close in the building (making it weather-tight) faster, allowing other trades to begin their work sooner and completing ahead of schedule, expediting the overall completion timeframe compared to a wood-framed building.
3. What costs are encountered in these projects?
Building with ICF in the construction project often results in large savings over the lifespan of the building.
One of the biggest fees encountered in the conversion of a plan for use with ICF construction is the need to pay the original designer of the plans to alter their drawings. They might insist that they are the only ones permitted to alter the plans, which could result in a fee in the region of $1000. However, that fee is small if it means avoiding potential copyright issues down the line.
The U.S. Department of Housing and Urban Development reports that “using ICF wall construction generally adds about 3 to 5 percent to the total purchase price of a typical woodframe home and land (about 5 to 10 percent of the house construction cost).”
For a 2,500 square-foot, two-story home and lot, the additional cost is around $7,000. While there are extra costs up front, this needs to be weighed against longer-term financial benefits like energy savings, improved appraised values and a longer-lasting more resilient materials in the design.
4. What potential issues can be encountered during a plan conversion project?
The thicker ICF walls means that the walls have to be moved outwards, otherwise the interior spaces will be reduced in size. There are a few areas that have to be given special care, so the the building still adheres to building standards.
Firstly, if you move the walls outwards, the building footprint will grow, so take note if you’re building on a tight lot. Also, as the walls move outwards, the roof will also become larger and it is essential that this is accounted for.
Garages are usually tight spaces, designed for little more that the entry of a car or two. Utilizing ICF construction rather than traditional timber frames means that the interior garage space can end up being too small for the cars to enter, if the architect does not take special care when altering the plans.
“If a lot is cramped, some rooms will have to be changed,” says Jim Zirkle of Home Design Services. “There are limits to how small you can go, especially with rooms involving plumbing, such as bathrooms, the kitchen and laundry room. Some changes are easy to accommodate and some take actual redesigning based on where they are placed in the floor plan. We look at those first when doing a conversion."
Zirkle also notes that the conversion plan should account for any updates in building code. ICFs are recognized and identified in the building codes with specific standards and engineering tables.
5. What are the main benefits of converting a traditional plan to ICF?
ICFs are a sustainable and cost effective way of building, and their use in any project can reduce build-time to completion dramatically.
One of the main benefits of an ICF plan conversion is the additional energy savings that can be attained when using ICF instead of traditional timber frame construction. The report from HUD states that “ICF construction, in general, provides improved energy efficiency relative to standard home construction practices.”
Saving on energy isn’t the only way that ICF delivers. Designing with ICF over traditional wood frame construction means a higher-performing structure: improved disaster-resilience, fire protection plus higher durability, security and comfort.
Convert to a Design That's Future-Forward
Converting a plan to be ICF-ready is relatively straightforward, and permits homeowners and designers to optimize a traditional design with the most innovative materials on the market.
Have more questions about converting your home design for ICF construction? Get in touch with us today to go over your plans.