Is an ICF house faster to build?
The assem­bly and place­ment of con­crete may take the same time as to build with con­ven­tion­al meth­ods. The advan­tage with Fox Blocks is that the walls are now insu­lat­ed, have a vapor and air bar­ri­er installed and are ready for fin­ish­es once the win­dows and roof are installed. These ben­e­fits will save weeks and/​or months depend­ing on the size of the projects.
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.

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.
Why is the concrete limited to a placement height or lifts of 4 feet (1.2 m)?
To alle­vi­ate the pres­sure from the liq­uid con­crete, the con­crete is placed in lay­ers or lifts’. The first lift is lim­it­ed to 4′ (1.2 m) of con­crete around the perime­ter of the build­ing. This allows approx­i­mate­ly one hour for the con­crete to set-up before con­tin­u­ing with the next 4′ (1.2 m) lift. The low­er lift pro­vides sup­port for the next lift as the con­crete is placed con­tin­u­ous­ly around the build­ing in con­sec­u­tive lifts to the top of the wall.
Do I need an engineer to design and stamp Fox Blocks building plans?
Fox Blocks are list­ed in the build­ing codes (IRC- Sec­tions R404, R611 or NBCC Part 9) with spe­cif­ic applic­a­bil­i­ty lim­its for res­i­den­tial con­struc­tion. If the project meets the applic­a­bil­i­ty lim­its with­in the build­ing code, a Pro­fes­sion­al Engi­neer may not be required (depen­dent on local build­ing depart­ment require­ments). A build­ing offi­cial has the right to request engi­neer­ing and in some regions all projects require a professional’s stamp. For any projects that exceed the applic­a­bil­i­ty lim­its, a Pro­fes­sion­al Engi­neer is required for the struc­tur­al design. Check with your local build­ing depart­ment.
Do I have to finish my basement walls with drywall?
All build­ing codes in the USA and Cana­da spec­i­fy that plas­tic insu­la­tion (EPS) must be cov­ered by a ther­mal bar­ri­er equiv­a­lent to 15 min­utes of fire pro­tec­tion in hab­it­able spaces. If the base­ment is clas­si­fied as hab­it­able space, then gyp­sum board must be applied but does have to taped and filled. Check with your local build­ing offi­cial.
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 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.

Is EPS the same as XPS?
No, these insu­la­tion prod­ucts are quite dif­fer­ent. EPS is closed cell expand­ed poly­styrene, while XPS is a closed cell extrud­ed poly­styrene. The prop­er­ties, appli­ca­tions and costs of each are quite dif­fer­ent. The major­i­ty of ICFs are man­u­fac­tured with EPS.