Is a high performance ICF home less expensive to build than a wood framed high performance home?
Yes, mar­gin­al­ly high­er on the ini­tial cap­i­tal costs, but, it is a record­ed fact that Fox Blocks high per­for­mance homes out per­form in com­fort and oper­at­ing costs over a wood framed home. These cre­ates month­ly cost sav­ings for the life cycle of the Fox Blocks home.
What is the R-Value?

The clear R‑Value of an Fox Blocks is R22, how­ev­er cur­rent Ener­gy codes rec­og­nize the lack of ther­mal bridg­ing in an ICF and the con­tri­bu­tion of the mass con­crete on the influ­ence of the ther­mal per­for­mance. Whole wall cal­cu­la­tions indi­cate a Fox blocks wall assem­bly pro­vides an R24 rat­ing.

The con­tin­u­ous dou­ble lay­er (inside and out­side) of insu­la­tion, the elim­i­na­tion of ther­mal bridg­ing and min­i­mal air infil­tra­tion through the mass con­crete wall assem­bly, allows Fox Blocks walls to per­for­mance in the high per­for­mance wall assem­bly cat­e­go­ry. Com­plet­ing the enve­lope with ener­gy effi­cient win­dows and doors and roof insu­la­tion, Fox Blocks homes can eas­i­ly meet and exceed ener­gy code require­ments and exceed the min­i­mum require­ments for Ener­gy Star and Ener­Guide. A Fox Blocks struc­ture requires 44% less ener­gy to heat and 32% less ener­gy to cool.

What do termites do to the foam?
EPS pro­vides no nutri­ent val­ue and is not a food source for ter­mites. If left exposed, ter­mites may tun­nel into the foam in search of fibrous food. When build­ing, in a heavy ter­mite infes­ta­tion area, care is required in the detail­ing and con­struc­tion of the walls that will be in con­tact with ground, to pre­vent access to the foam for ter­mites.
Is EPS the same as XPS?
No, these insu­la­tion prod­ucts are quite dif­fer­ent. EPS is closed cell expand­ed poly­styrene, while XPS is a closed cell extrud­ed poly­styrene. The prop­er­ties, appli­ca­tions and costs of each are quite dif­fer­ent. The major­i­ty of ICFs are man­u­fac­tured with EPS.
Does the Fox Blocks contain recycled materials?
The plas­tic webs in Fox Blocks forms are 100% recy­cled postin­dus­tri­al polypropy­lene. The EPS insu­la­tion is vir­gin mate­r­i­al. Recy­cled con­tent for an ICF block is mea­sured by weight. The recy­cled con­tent by weight of a stan­dard 6″ Fox Blocks form — 48%.
What is EPS made from?
Poly­styrene is vir­gin mate­r­i­al, man­u­fac­tured from petro­le­um. Poly­styrene beads are expand­ed with steam heat to be up to 40 times their orig­i­nal vol­ume and then the expand­ed beads are mold­ed again by steam heat into 258″ rigid insu­la­tion pan­els to cre­ate a Fox Blocks ICF.
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
Are there different types of Expanded Polystyrene (EPS)?
EPS is list­ed basi­cal­ly under four prop­er­ty clas­si­fi­ca­tions – Type I, II, III and IV. The char­ac­ter­is­tics are based on the den­si­ty of the mold­ed foam which defines the prod­uct type. Fox Blocks ICFs are man­u­fac­tured as a Type II EPS with a den­si­ty of approx­i­mate­ly 1.5 pounds per cubic foot.
When is a Taper Top form required?
Taper Top forms are specif­i­cal­ly designed to pro­vide a larg­er bear­ing sur­face along the top of the wall. Typ­i­cal­ly, the increased bear­ing sur­face may be used to sup­port mason­ry, floor or roof loads. Taper top forms are used in the tran­si­tion from ICF to wood frame con­struc­tion and the taper top form would be the top form on the wall.
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.