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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.

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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)
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What do termites do to the foam?
EPS pro­vides no nutri­ent val­ue and is not a food source for ter­mites. If left exposed, ter­mites may tun­nel into the foam in search of fibrous food. When build­ing, in a heavy ter­mite infes­ta­tion area, care is required in the detail­ing and con­struc­tion of the walls that will be in con­tact with ground, to pre­vent access to the foam for ter­mites.
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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.
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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.
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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 1⁄3 over the EPS and bears 2⁄3 on the con­crete is allow­able. This can be done with a min­i­mum 2 x 6 plate. If a 2 x 4 plate is required, a taper top form should be used to extend the con­crete under the plate.
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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.
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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.
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Is installing ICFs a DIY project?
Fox Blocks rec­om­mends that all installers using Fox Blocks ICFs com­plete a Fox Blocks train­ing pro­gram to ensure they have a bet­ter under­stand­ing of the basics. How­ev­er, for first time installers, it is pre­ferred that a Fox Blocks trained, expe­ri­enced installer inspect the instal­la­tion pri­or to place­ment of con­crete and assist in the place­ment of the con­crete, as they are famil­iar with work­ing with con­crete and can ensure the build is struc­tural­ly sound and safe and the walls are con­sol­i­dat­ed prop­er­ly, built straight and plumb.
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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.

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