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.
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.
Do ICFs require a special concrete mix design?
The con­crete is nor­mal strength, min­i­mum 2500 psi (20 MPa) per build­ing codes. The mix design spec­i­fies a small­er aggre­gate and high­er slump than con­crete typ­i­cal­ly used for floors. Most Ready-Mix sup­pli­ers are famil­iar with an ICF con­crete mix design.
Is an ICF home quieter than a stick framed home?
Absolute­ly. The exte­ri­or walls are two lay­ers of con­tin­u­ous insu­la­tion, the den­si­ty of sol­id con­crete and a lay­er of ½” gyp­sum board on the inside all con­tribute to supe­ri­or sound sup­pres­sion of STC 50 for the whole build­ing enve­lope. Note: A wood frame sys­tem of equiv­a­lent STC rat­ing would be 2 x 4 studs spaced 16˝ o/​c, with 3½˝ absorp­tive mate­r­i­al, 1 lay­er of 5 /8˝ Type X gyp­sum board on resilient chan­nels spaced 16˝ o/​c, and 2 lay­ers of 5 /8˝ Type X gyp­sum board on the oth­er side. (Cour­tesy of 1995 NBCC Sec­tion A9.10.3.1 Wall #W5a)
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%.
Is the Fox Blocks form recyclable?
Yes, every com­po­nent of the Fox Blocks form itself plus the con­crete and rein­force­ment bars are recy­clable.
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.

Is a vapor barrier required on the inside face of an ICF wall?
No. The char­ac­ter­is­tics of an ICF wall with the mass con­crete and the EPS insu­la­tion pro­vide the required vapor per­me­ance to meet build­ing code require­ments as a vapor bar­ri­er.
What exterior finishes can be used on an ICF?
Fox Blocks are com­pat­i­ble with all exte­ri­or fin­ish mate­ri­als and sys­tems – sid­ing, stuc­co, mason­ry veneer, sim­u­lat­ed stone, etc. The attach­ment of cer­tain exte­ri­or fin­ish­ing sys­tems is rec­om­mend­ed with exte­ri­or grade screws fas­tened into the exposed or con­cealed webs.