Is there a problem when placing concrete, dropping concrete from the top of the wall which may be over 8' (2.4 m)?
No. Specifications in the America Concrete Institute (ACI) do not limit the maximum distance concrete can free fall. Engineering studies and reports have shown that free fall from up to 35′ doesn’t reduce concrete quality and there is no evidence of segregation or weakened concrete strength. ICF concrete design calls for a high slump mix which assists in reducing segregation.
Can you build and pour concrete in cold weather?
Yes. The forms insulate the concrete and enhance the curing process. The top of the forms, or exposed concrete areas will need to be covered, temporarily, with insulation to prevent the exposed concrete from freezing. Fox Blocks projects can be constructed any time of the year, no delays for cold weather.
How do you control voids in the wall?
The concrete mix is a high slump 5″- 6.5″ (125 mm – 165 mm) with a smaller aggregate size so the concrete flows easily. The person in charge of placing the concrete should watch the concrete flow throughout the whole wall to ensure there are no void pockets. Internal vibrating provides good consolidation, eliminating voids.
What size and how much steel reinforcement is required in an ICF?
Fox Blocks walls are designed as reinforced concrete walls, with steel reinforcement bars specified to be installed vertically and horizontally, as the walls are built. Typical reinforcement bar sizes used are #4 or #5 (10 m or 15 m).
Does expanded polystyrene (EPS) present a serious fire hazard?
The EPS in an Fox Blocks has a flame retardant that allows the forms to be flame resistant. The EPS will melt when exposed to sustained temperatures over 300°F (149°C). The ignition point of the melted styrene is 600°F (315°C) (wood is approximately 500°F (260°C). Fox Blocks have been tested to meet the building code requirements for flame spread and smoke development, plus Fox Blocks may be used as fire resistant rated wall assemblies in schools and hospitals.
Is burning EPS toxic?
Test reports conducted by the National Research Council state: “The maximum toxicity index obtained from the combustion of polystyrene was of the same order as that of wood.” Fox Blocks ICFs have been tested to meet building code requirements for flame spread ratings, smoke development and toxicity
How are Fox Blocks green/environmentally friendly?
Fox Blocks contain a minimum of 40% recycled content by weight.
- Fox Blocks do not off-gas and are not manufactured using any gases that deplete the ozone or are harmful to the environment.
- Fox Blocks require low embodied energy to manufacture.
- Fox Blocks do not contain any materials, that promote mold or mildew growth.
- Fox Blocks are an efficient construction method thereby reducing the amount of construction waste, dust and air pollution in the building process.
- Building with Fox Blocks will save on heating and cooling costs because less air is exchanged between the outside and inside of your home. This also means a smaller more efficient HVAC unit is required for the home.
- Fox Blocks are sustainable. They will not rot or deteriorate for the life of your home.
- Fox Blocks provide a secure, durable, comfortable, long lasting building
Is the Fox Blocks ICF product ‘LEED’ rated or certified?
Products are not rated or certified under the LEED program. The overall building is evaluated and assigned a LEED rating. In the selection of building materials for a LEED design, Fox Blocks have many benefits that can enable, enhance or directly contribute toward LEED points for the project.
Is the Fox Blocks product rated by ‘Energy Star’?
Energy Star does not evaluate or rate insulation products. Every Fox Blocks home when tested by an Energy Rater, can meet and exceed the Energy Star home standards and achieve a 5 Star rating and a ‘HERS’ score well below the minimum Energy Star requirement of 85, or in Canada, higher than an EnerGuide rating of 80.
Does EPS ‘off gas’?
EPS does not off-gas. Fox Blocks forms do not and never have contained any CFC or HCFC products. The forms are made by a steam process that utilizes ‘pentene gas’ as a blowing agent. The blowing agent dissipates from the product within 48 hours of manufacturing. Fox Blocks forms are odorless, do not deteriorate, and do not off gas.