- What thermal efficiency results will I achieve with ICF?
- What will ICF construction mean for the future value of my home?
- How does ICF compare to concrete block or poured wall construction?
- How much does it cost to build with ICF compared to other building materials?
- Do you have to use special plans for the ICF System?
- Can we use stucco on the ICF Forms?
- What does an ICF house look like when it is finished?
- How are exterior finishes attached?
- How do you connect internal frame walls to the ICF wall?
- How are grab bars, towel bars, other fixtures installed?
- How is drywall attached?
- How do you run the electrical and plumbing?
- How are doors and windows installed?
- Where does the moisture from the concrete go once it has been poured into the forms?
- We would like to build our house ourselves. Can we buy your system and install it?
- Are there limitations on what kind of structure you can build with ICF?
- How tall can you build with the ICF?
- What are the physical differences between an ICF wall and traditional wall?
- How long will an ICF structure last?
- What are the advantages of building with ICF?
- What are ICFs?
What thermal efficiency results will I achieve with ICF?
R-Value is a term given to the property of any material to "resist" the conduction of heat. R-Value as a property is legitimate. The functional design of the laboratory determination of this property, relative to commercial insulation and building materials, is flawed at a fundamental level since performance predictions using heat transfer calculations based on tested and published R-values alone do not accurately predict real-world performance. Amvic ICf alone has an R-Value of 22, however When the mass and thermal efficiency of the concrete core is taken into account, Amvic ICF can achieve a thermal efficiency equivalent to R-50 depending on the size of the core.
What will ICF construction mean for the future value of my home?
As energy costs continue to rise, and as ICF construction is more widely understood and appreciated it is reasonable to project that ICF houses will command a 10-15% premium over comparable stick-built homes in the not too distant future.
How does ICF compare to concrete block or poured wall construction?
When cured, the concrete in Amvic walls is 50% stronger and use 30% less concrete than traditionally poured walls. While the cost of a bare block or poured wall is less, Amvic provides insulation and furring strips, and is ready to finish, making it a cost effective and less labor-intensive choice. Amvic also is far less labor intensive to use where there are frequent openings and/or pop outs as are frequently the case in residential construction.
How much does it cost to build with ICF compared to other building materials?
This isn't a simple question to answer. Best case is that it the same or slightly cheaper than framing with 2X4 construction. The worst case is up to a 4% greater project cost. The walls themselves cost more than equivalent wood framed walls. That's only a part of the story however. With an experienced crew, the walls will go up faster than stick framing. There are construction savings on studding, vapor barrier, insulation, prepping for an exterior hard coat, reduced waste, and on sizing heating and air conditioning equipment, which can be reduced due to the thermal efficiency of the Amvic building. If you are building on a hillside and would need to form a retaining wall, then building with the Amvic system will be more cost effective than building conventionally. Probably the best working assumption is to assume either the same cost as stick frame up to a 1-2% increase in cost to go with Amvic.
Building with Amvic is comparable in cost to building with 2x6 wall construction. The AMVIC wall will give you an effective insulation value of R32, much greater than a 2x6 wall allowing you to save 50-80% on your heating and cooling costs and rapidly becoming cheaper than stick framing over a very few years.
Do you have to use special plans for the ICF System?
No. Conventional house plans can be used, you must simply have the exterior wall dimensions increased to accommodate the Amvic walls.
Can we use stucco on the ICF Forms?
Yes. Any type of stucco can be applied directly to the EPS Forms.
What does an ICF house look like when it is finished?
An Amvic home looks like any conventional new home on the outside and inside. The window sills are deeper since the walls are thicker. Very few people can tell the difference between ICF construction and other types of construction.
How are exterior finishes attached?
Stucco (acrylic or cementations) is adhered directly to the foam. Wood, plastic or metal cladding is mechanically fastened to the embedded plastic ties. Stone and brick are attached according to design specifications.
How do you connect internal frame walls to the ICF wall?
For regular walls, if the stud lands over a web, screw through the stud with a 3" deck screw and connect to the web. If it doesn't span a web, you can use Grapplers (see previous question) or just spring the stud out and use an adhesive such as Foam2Foam polyurethane foam, liquid nails or similar and glue the face of the 2X to the foam. In the uncommon case where the frame wall is a shear wall, then use anchor bolts or Simpson Ties just like you're installing a ledger and bolt the stud to the concrete.
How are grab bars, towel bars, other fixtures installed?
Fixtures can be screwed into the webs (there is one every six inches), or installed using molly bolts through the sheetrock. Alternatively backing can be installed between the sheetrock and the block. One method is to use a hot knife and skin off 1/2 inch of the foam (flush with the webs) and install a strip of 1/2 inch plywood that is screwed into the webs wherever possible. Then fasteners can be screwed into the plywood at any point. A second and easier method is to use Windlock Grapplers. These are 4" x 6" perforated steel plates' corners dig into the foam and when sheetrock is applied over it they become firmly locked in place. A fastener can then be screwed in at any point and it will pierce and lock into the Grappler backing.
How is drywall attached?
Mechanically with drywall / gypsum screws into the polypropylene webs. Frequently an EPS compatible adhesive such as Foam2Foam is used with the screws.
How do you run the electrical and plumbing?
Some of the utilities are placed prior to the pour, and others are done afterwards. Services access cavities need to be cut before the pour. Just use a saw, utility knife or hot knife to cut through the blocks. Then place the service pipes (or sleeves) in the openings. The gaps should be foamed to prevent concrete leakage during the pour. Once the pour is complete cavities for wiring and plumbing can be cut into the surface using a router, chainsaw, or hot knife. Place the services in chase. Generally, the Romex will be a friction fit into the groove. Occasionally a drop of foam is used to hold it in place much like a staple. Make sure to observe all code requirements. If vents have to be run in exterior walls, they may need to be placed in the cavity of the block prior to the pour. Generally, it is easiest to plan the layout of utilities to minimize use of the exterior walls.
How are doors and windows installed?
A wooden or vinyl buck is built to the desired rough opening size and incorporated into the AMVIC wall as it is being stacked prior to pouring the concrete. Once the concrete cures, doors and windows are installed as usual into this opening.
Where does the moisture from the concrete go once it has been poured into the forms?
Concrete must have water to gain strength and hydrating membranes are an essential part of concrete construction. When ICF is used, the concrete achieves a higher strength than specifications because of this ability to keep moisture in the mix. Eventually, all the water is converted to concrete crystals.
We would like to build our house ourselves. Can we buy your system and install it?
Yes. You can install the Amvic Building System by yourself. You should, however employ an ICF contractor to assist you with the final pre-pour check and concrete placement.
Are there limitations on what kind of structure you can build with ICF?
No. Virtually any design that can be built conventionally can be built with Amvic ICF.
How tall can you build with the ICF?
A structural engineer should design multi-story structures built with Amvic, but the sky is the limit.
What are the physical differences between an ICF wall and traditional wall?
An Amvic wall is stronger, more soundproof, more resistant to natural disasters, better insulated, has a superior R-value, is more energy efficient and reduces air infiltration. In addition it also provides numerous benefits from the thermal mass of the concrete.
How long will an ICF structure last?
Concrete walls built with Amvic ICFs may last in excess of 100 years with minimal maintenance required to the walls. This is at least 4 times longer than traditional construction.
What are the advantages of building with ICF?
Amvic ICF structures require 30-50% less energy to heat and cool when used in conjunction with other energy saving products They are also wind, fire and insect and rodent resistant as well as provide a safe, quiet and comfortable atmosphere for homeowners for many years.
What are ICFs?
Amvic ICFs are hollow, light-weight "stay in place" forms made of two Expanded Polystyrene (EPS) panels which are connected by polypropylene webs. During construction, the forms are stacked to the desired height then filled with concrete making stable, durable and sustainable walls. They offer a "5 in 1" solution that provides structure, insulation, vapor barrier, sound barrier and attachments for drywall and exterior siding in one easy step which dramatically reduces labor costs and construction time.