Ten Most Frequently Asked Questions

1.  What is an ICF?

        An ICF is an Insulated Concrete Form.  Quite simply it is a stay in place form that holds rebar and concrete.  In a one step application it provides you with four features - structural stability, insulation, furring strips and vapor barrier.

1a.  What an Amvic ICF is not!!

        A form you use only for basements.

        A form that requires engineers and architects to re-write their PhDs on.

        A form that requires extensive tying of reinforcing rod.

        A form that requires high skill levels to use.

        A form you use and then strip away the foam.

2.  Can I use an ICF for a basement wall?

        The first patents for ICF's were registered by a Canadian, specifically for basement applications.  The biggest marketing challenge our industry has is getting people thinking above grade.  One and two story homes, high-rise and Townhouse developments, swimming pools, retaining walls, Potato barns etc.

3.  Do I have to cover the ICF wall below grade to prevent water migration?

        Yes,  A number of products are available to you from spray applications, plastic wraps to peel and stick. 

4.  What is the cost comparison of an ICF home over conventional stick frame construction?

        This is a complex question to answer because of regional differences in ready-mix, labor and energy as well as the complexity of the structure.  The Portland Cement Association estimates that on the average a home built with an ICF envelope will be between 5-8% more expensive.  For example a simple $100,000 home will cost you around $108,000.  You have to remember though you now have a finished insulated basement with this structure.  Most builders use different comparisons but do not properly explain this fact.  Dramatically rising energy costs now can very quickly offset the premiums associated with ICF construction.  The consumer can accommodate a predictable mortgage rate but end of the month surprises can cause unnecessary financial strains.

5.  What is the fire rating of an ICF structure?

        First off all ICF manufactured blocks have a flame retardant added to the foam.  If you hold a lit match to the block it will go out once the heat source is removed.  Codes require that ICF's be covered with gypsum board in which case you have a substantial 3 hour minimum fire rating.  ICF's are the answer for the maximum fire protection available today and obviously ideal for remote locations.

6.  What is the R-value of an Amvic ICF wall?

        The effective R-value of our wall is R22.  But the wall with its substantial thermal mass "performs" up to an R50 wall.  In other words you would have to pack a traditional stick frame wall out to an R50 to get it to perform the same way an Amvic wall does.  The PCA has also estimated that it takes approximately 8-10 hours for changes in outside temperatures to travel through an ICF wall and affect inside comfort.  In many cases now dramatically rising energy costs.

7.  Can I build my own ICF house?

        We would prefer that all ICF shells be built by qualified builders who understand the risks involved in construction.  We do not encourage homeowners to build their own ICF walls unless they are supervised by a qualified individual.  Remember a ten-foot by ten-foot section of wall weighs 5000 lbs.  A homeowner will have almost 60% work left to do once the shell is up.

8.  Will bugs or termites eat my home?

        There is no food value in EPS but bugs do like to nest in its warmth.  Proper attention to detail preventing any egress into the foam removes this concern.  Some areas of North America are being infested by termites driving ICF's and alternatives to wood to the forefront of construction.  Interesting enough some of the first proponents of ICF's were because of their dislike of bug invasions long before our current situation. 

9.  Will I be protected in my home in the event of a severe storm?

        Contrary to popular belief most fatalities from severe storms are caused by air born missiles not buildings collapsing.  A two by four shot at gale force winds at a standard brick veneer stick built home penetrates right through the wall.  Obviously ICF's are the safe answer to our ever-increasing dangerous weather systems.  People forget what the true function of a home is.  Its shelter from the storm not the Corian countertop.  Insurance companies are starting to offer preferred rates to individuals who utilize ICF technology.

10.  Is one limited with design criteria when building with ICF's?  Do you need special plans.

        Mankind has been building with reinforced concrete since 1857.  It has tremendous spanning capabilities.  Long insulated window lintels are now possible.  ICF blocks can be cut to accommodate curved walls.  ICF walls can accommodate a whole array of floor systems from conventional timbers to precast to insulated poured in place.  Plans can be easily accommodated to utilize ICF's if one remembers to work with the block dimensions. In fact if you think about it, details can be presented much more easily.