How do I determine which size ICF to use?

ICFs pro­vide a rein­forced con­crete wall which is designed to spe­cif­ic engi­neer­ing prin­ci­ples. Typ­i­cal res­i­den­tial con­struc­tion, per the applic­a­bil­i­ty lim­its in the build­ing code, allows walls 10′ (3 m) high or less between lat­er­al sup­ports (floor and roof con­nec­tions). Below grade walls must have a min­i­mum 6″ (150 mm) con­crete core. In some regions, an 8″ (200 mm) con­crete core is the min­i­mum allowed thick­ness for below grade walls.

The 4″ (100 mm) form can­not be used below grade as a foun­da­tion wall. The 4″ (100 mm) form may be used for above grade walls up to a max­i­mum of 10′ (3.0 m).

The 6″ (150 mm) form, above grade, is lim­it­ed to approx­i­mate­ly 14′ (4.2 m) in height. Walls high­er than 14′ (4.2 m) must use an 8″ (200 mm) or larg­er form.

Typ­i­cal res­i­den­tial con­struc­tion will use 6″ or 8″ con­crete core size blocks. Project spe­cif­ic engi­neer­ing may allow for some core thick­ness to span ver­ti­cal­ly high­er than these pro­posed guide­lines.

Can you vibrate or consolidate the concrete in ICFs?
Yes, con­sol­i­da­tion of the con­crete is one of the key ele­ments in the place­ment of con­crete in an ICF wall. Fox Blocks rec­om­mends inter­nal vibra­tion with a pen­cil vibra­tor, quick­ly in and slow­ly out.
How does the ICF block get secured to the foundation?
The ICF blocks are held in place with either low expan­sion spray foam or a met­al starter track. The bracing/​alignment sys­tem, typ­i­cal­ly installed after the 4th course of block, also sup­ports the ICFs in place. Once the con­crete is in the wall there is no con­cern with the forms mov­ing. The con­crete is con­nect­ed to the foot­ing with rein­forc­ing dow­els.
How do I apply an acrylic stucco finish to an ICF?
Acrylic stuc­co is a thin coat fin­ish which can be direct­ly applied to the EPS insu­la­tion on the exte­ri­or face of the ICF. Fox Blocks pro­vides a con­tin­u­ous EPS sur­face con­ducive for the appli­ca­tion of acrylic stuc­co. All acrylic stuc­co man­u­fac­tures are famil­iar with ICFs as a sub­strate and each have their rec­om­men­da­tions for appli­ca­tion over ICFs. Note there is a dif­fer­ence in the instal­la­tion pro­ce­dures between acrylic stuc­co and tra­di­tion­al stuc­co.
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)
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.
Do you need special code approvals to build with Fox Blocks ICFs?
No, ICFs in gen­er­al are cov­ered in the build­ing code and Fox Blocks ICF has a prod­uct eval­u­a­tion report that con­firms the prod­uct and appli­ca­tions meet the require­ments of the respec­tive build­ing codes in the USA and Cana­da. These reports are avail­able on our web­site.
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).

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.
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.