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.
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 if my contractor doesn’t know how to build with it?
Fox Blocks offers the most com­pre­hen­sive installer train­ing in the indus­try. We can train your con­trac­tor or help you locate a trained installer in your area.
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.
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.
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.
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
Can you build and pour concrete in cold weather?
Yes. The forms insu­late the con­crete and enhance the cur­ing process. The top of the forms, or exposed con­crete areas will need to be cov­ered, tem­porar­i­ly, with insu­la­tion to pre­vent the exposed con­crete from freez­ing. Fox Blocks projects can be con­struct­ed any time of the year, no delays for cold weath­er.
Can the plastic webs be detected by using stud finders?

A stud find­er typ­i­cal­ly uses the den­si­ty of mate­ri­als to locate studs. The polypropy­lene (plas­tic) web mate­r­i­al will show up on high qual­i­ty den­si­ty stud find­ers. Note, the webs in Fox Blocks are spaced at 8″ (200 mm) on cen­ter and will be con­tin­u­ous ver­ti­cal­ly on each side of the wall.