Does the EPS provide support for a wood sill plate?
No, the EPS has no struc­tur­al capac­i­ty to sup­port any loads. Wood sill plates must achieve the required bear­ing from the con­crete with­in the ICF. A wood plate that can­tilevers 13 over the EPS and bears 23 on the con­crete is allow­able. This can be done with a min­i­mum 2 x 6 plate. If a 24 plate is required, a taper top form should be used to extend the con­crete under the plate.
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.
How much will it cost per square foot to build an Fox Blocks ICF home?

Build­ing with Fox Blocks ICFs pro­vides you with a high per­for­mance wall sys­tem for the foun­da­tion and above grade walls. Build­ing any high per­for­mance home, with either ICFs or con­ven­tion­al wood fram­ing, has many fac­tors that define the end cap­i­tal costs.

What addi­tion­al mate­ri­als and labor are required to make a con­ven­tion­al foun­da­tion equiv­a­lent to an Fox Blocks ICF foun­da­tion which exceeds ener­gy code require­ments in most loca­tions? Con­ven­tion­al wood fram­ing requires con­sid­er­ably more mate­r­i­al, insu­la­tion and atten­tion to air seal­ing to make it qual­i­fy and per­form as a high per­for­mance wall. All of this, for con­ven­tion­al con­struc­tion, adds mate­r­i­al and labor costs to the over­all project. Fox Blocks ICFs pro­vide a sim­ple method to build high per­for­mance walls that pro­vide ongo­ing ben­e­fits from the high insu­la­tion val­ues and mass con­crete walls that are ener­gy-effi­cient and pro­vide cost sav­ings for the life cycle of the build­ing.

Com­par­ing cost per square foot between con­ven­tion­al con­struc­tion and ICFs for a high per­for­mance build­ing, is like com­par­ing apples to oranges. To devel­op con­struc­tion costs, more detailed infor­ma­tion is required, for instance the num­ber and size of open­ings, the shape and size of the home, the region­al costs for mate­r­i­al and labor, etc. If you have a project you’d like us to review and pro­vide a mate­r­i­al esti­mate, Fox Blocks would be hap­py to have one of our rep­re­sen­ta­tives con­tact you. Please com­plete and sub­mit a lead infor­ma­tion sheet on the web­site or call Cus­tomer Ser­vice.

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
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.
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 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)
What is a ‘blow-out’?

A blow-out’ is a break in the form, gen­er­al­ly due to the pres­sure from the liq­uid con­crete dur­ing the con­crete place­ment and/​or con­sol­i­da­tion. Fox Blocks ICFs are designed to main­tain a high safe­ty fac­tor of pres­sure from the liq­uid con­crete. Dam­aged forms or fail­ure to sup­port areas where forms have been cut leav­ing a large area of EPS between the web sup­ports may cause a blow-out. Over con­sol­i­da­tion may also cause a blow-out.

Fox Blocks rec­om­mends the Pre-Place­ment Check­list be reviewed for all wall assem­blies pri­or to the place­ment of con­crete, to find poten­tial prob­lem areas and install addi­tion­al strap­ping or sup­port to pre­vent blow-outs. Gen­er­al­ly, for an Fox Blocks form, the size of a blow-out may be lim­it­ed to the EPS between the webs, 6″ or 8″ wide by the height of one form. If a blow-out occurs, the con­crete pour moves to anoth­er area on the wall, the hole is patched by replac­ing the EPS, installing wood sup­port over the area, and then resum­ing the pour.