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.
Can masonry be installed on the exterior walls?
Yes, Fox Blocks has a brick ledge form and the xLer­a­tor ledge rein­force­ment that is designed to sup­port mason­ry. Fox blocks also has a tieKey acces­so­ry which is a specif­i­cal­ly made as a mason­ry tie, to be insert­ed through the form into the con­crete.
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.
What fasteners are recommended for ICFs?

Fox Blocks has con­duct­ed numer­ous fas­ten­er tests for pull-out strength and shear capac­i­ty for var­i­ous fas­ten­ers – screws, ring shank nails and sta­ples into the plas­tic webs. The rec­om­men­da­tion for inte­ri­or and exte­ri­or appli­ca­tions of fin­ish mate­ri­als is for the use of screws which pro­vide the best hold­ing capac­i­ty into the plas­tic webs or fas­ten­ing strips in the forms which are iden­ti­fied on each block.

The EPS insu­la­tion does not pro­vide any hold­ing capac­i­ty for fas­ten­ers.

Can I leave Fox Blocks forms exposed to ultraviolet rays for an extended period (months)?
Yes, but you will notice a light dust­ing on the sur­face and a yel­low­ing dis­col­oration of the forms. This does not indi­cate any detri­men­tal effects to the ICFs. We do sug­gest, that if the exte­ri­or fin­ish is not going to be installed with­in around a 3 month peri­od or more, the forms be pro­tect­ed from UV rays by installing a tem­po­rary build­ing wrap type mate­r­i­al. The pow­dery film must be removed with soap and water before the appli­ca­tion of a syn­thet­ic stuc­co fin­ish or water­proof­ing mem­brane.
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)