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1 7001 Diamond Snap-Form ICF Code Considerations With the multitude of lightweight onrete forming systems in the onstrution market, building offiials are raising questions about ode ompliane and/or ode evaluation reports for these systems. The two basi types of lightweight onrete forming systems are foam bloks and the plank and tie systems. Blok-type systems redue the area of onrete in the wall and may be required to have evaluation reports to address their design. The plank and tie forms, generally, do not redue the volume of onrete in the wall; therefore, separate evaluation reports for the apaity of the finished onrete wall are not required for plank and tie systems. The Diamond Snap-Form (DSF) ICF System is a plank and tie system whih does not hange the physial properties or the onfiguration of the onrete wall. It funtions identially to a plywood or metal form system. That is to say, the form holds the wet onrete in plae until the onrete has suffiient strength to support itself. The design requirements for the onrete formed with the DSF ICF System are the same as with any other onrete wall. Rebar is still required in the horizontal and vertial diretions as designed by the strutural engineer or stipulated by ode minimums. Calulations for the spaing of the Diamond Snap-Ties and the apaity of the EPS are inluded with this tehnial bulletin. DSF has onduted field and laboratory testing whih determined tension values for the Diamond Snap-Ties (6, 8, and 10 ) at pounds. Based on this data, DSF reommends that a pour rate of three to four feet per hour is appropriate. This, as well as the minimum braing needed to assure plumb and true walls, is shown in our tehnial data. The Foam-Control EPS with Perform Guard used in the DSF ICF System is produed under a third party quality ontrol program and is UL listed with flame spread and smoke development ratings that meet major model building odes. Various setions of the odes that deal with onrete formwork state that the design of the formwork shall inlude onsideration of rate and method of plaing onrete and onstrution loading. Pursuant to these odes, building offiials have requested to see strutural information on the validity of the DSF ICF System. Copyright 2011

2 7002 Diamond Snap-Form ICF Srew Withdrawl Capaities The DSF ICF System is used in appliations where finish materials suh as drywall and sheet sidings are desired. The attahment of these types of finishes is aomplished by installing srews through the finishing material and into the tie fae of the Diamond Snap -Tie (referene the DSF ICF Constrution Manual). As support for these types of appliations, DSF onduted numerous srew withdrawal tests. In these tests, srews of various sizes and thread design were evaluated for resistane to withdrawal when pulled out of the fae of Diamond Snap-Ties. Tests showed only slight variation in the fore required to remove a variety of srew fastener types from the tie, irrespetive of srew diameter, thread design, or penetration depth. DSF reommendation for the ultimate withdrawal value of #6 through #14 srew fasteners plaed in Diamond Snap- Ties is 210 pounds per fastener. In all ases: the srew fastener must penetrate the full thikness of the Diamond Snap-Tie fae. The finishing materials manufaturers reommendations for fastener frequeny should be followed. Appliations exposed to weather onditions should utilize orrosion resistant fasteners. The data in this bulletin is an average ultimate withdrawal value. No fator of safety has been applied. An appropriate fator of safety must be used in design alulations. Copyright 2011

3 7003 Conrete - Wood Wall Strength Comparison Diamond Snap-Form has prepared a guide for strength omparison of onrete onstrution versus wood onstrution. Speifi onditions for omparison of eah wall type are presented in this bulletin. The variables are spelled out for eah material and the results follow. The wall omparisons are based on bending strengths only. The defletion limitations of the various materials are not onsidered. In designing a speifi projet, the servieability of the wall (i.e., the defletion requirements) must also be onsidered. ** NOTE: Comparisons given here are not to be used for any projet designs. They are stritly for information only. DSF reommends that the appliable ode requirements and the servies of a registered professional strutural engineer be used for the design of speifi projets. Situation: Exterior wall, 10 tall, wind loading only (i.e. no gravity load). Wall Type - Stud Wall: 2 x 4 Stud Wall 2 x 6 Stud Wall SPF #2 & better; SPF #2 & better; 2 x 16 o..; 2 x 16 o..; F b = 850 psi; F b = 850 psi; Capaity = 13 psf Capaity = 32 psf 2 x 8 Stud Wall 2 x 10 Stud Wall SPF #2 & better; SPF #2 & better; 2 x 16 o..; 2 x 16 o..; F b = 850 psi; F b = 850 psi; Capaity = 56 psf Capaity = 90 psf Wall Type - Reinfored Conrete: 4 Conrete Wall 6 Conrete Wall f 1 = 3000 psi; = #4 24 o..; F y = 60 ksi; Reinforing entered in 4 wall. Capaity = 59 psf 8 Conrete Wall f 1 = 1350 psi; = #4 24 o..; F y = 60 ksi; Reinforing entered in 8 wall. Capaity = 120 psf Wall Type - Unreinfored Conrete: 4 Conrete Wall 6 Conrete Wall f 1 = 3000 psi; = None; Capaity = 29 psf 8 Conrete Wall f 1 = 1350 psi; = None; Capaity = 117 psf f 1 = 3000 psi; = #4 24 o..; F y = 60 ksi; Reinforing entered in 6 wall. Capaity = 89 psf 10 Conrete Wall f 1 = 1350 psi; = #4 24 o..; F y = 60 ksi; Reinforing entered in 10 wall. Capaity = 150 psf f 1 = 3000 psi; = None; Capaity = 66 psf 10 Conrete Wall f 1 = 1350 psi; = None; Capaity = 183 psf Key: F b - bending stress strength level of the wood (SPF #2 usually rates 850 psi) Capaity refers to the wind load wall strength in pounds per square foot (psf) f 1 - ompressive strength of the onrete used (usually at 28 days ure time) - size of rebar in the wall (#4 = 1/2 inh diameter) and the spaing (24 inh O/C) F y - yield strength of the steel rebar - in this ase 60,000 pounds per square inh Copyright 2011

4 7004 Diamond Snap-Form ICF Corner Room Test Results The International Building Code (IBC) has speifi requirements when it omes to the appliation of foam plastis. The odes require the use of a thermal barrier overing the foam plasti, when the foam plasti is plaed toward the interior of habitable spae. This ode requirement does not inlude attis with limited aess, rawl spaes, or mehanial rooms, all of whih have alternate provisions within the odes. A reognized building produt used to meet these thermal barrier ode requirements is 1/2 gypsum board (other materials may qualify under the ode). In appliations where the DSF ICF System is utilized to reate a full basement or the main struture above grade, it is required that the Diamond Snap-Form ICF interior be overed with a thermal barrier. DSF ICF was subjeted to a Corner Room Burn (UL 1715, UBC 26-3) test at a third party laboratory to demonstrate that the appliation of gypsum over the DSF ICF System meets ode requirements for a thermal barrier. This test showed that the ode-required thermal barrier remained in plae through the fire test. Copyright 2011

5 7005 Real Time Aging of Diamond Snap-Form Ties Constrution projets may take weeks or even months to omplete. During this time, the omponents used in the onstrution are exposed to the elements. To demonstrate that the DSF ICF System is not negatively effeted by long term exterior exposure, DSF onduted field exposure tests on Diamond Snap-Ties. Diamond Snap-Form subjeted DSF Ties to the elements for an extended period of time - five months. During this time, the ties were mounted in both horizontal and vertial positions faing due south. At the onlusion of the exposure, the DSF Ties were tested for olor retention, srew holding power, and tensile strength. After this severe 1-1/2 year exposure to the elements, the weathered DSF Ties showed: Exellent olor retention. Srew holding apaities in exess of reommended values (see ICF Teh Bulletin #7002). Retained their omplete tensile strength DSF testing demonstrates that projets utilizing the DSF ICF System will maintain the neessary attahment strength harateristis under general onstrution time exposure. After five months of exposure to ambient outdoor onditions, the weathered DSF Ties showed: No olor hange Maintained their exellent srew holding apabilities (see ICF Teh. Bulletin #7002) Retained their omplete tensile strength In addition to the ontrolled experiment desribed, DSF also tested DSF Ties on a 1-1/2 year old onrete filled field exposed test wall. DSF monitored the appearane and tested the srew holding apaity of the exposed ties. The field exposed wall was loated in Denver, Colorado. It was subjeted to the harsh ultraviolet light exposure and temperature flutuations that Denver is known to experiene. Copyright 2011

6 7006 Conrete Consolidation in the Diamond Snap-Form ICF System Conrete form appliations that use rigid wood, steel or hard board require that onrete plaed within the form be onsolidated by vibration. The vibration requirement for these type of form materials is neessary to ensure that no voids or pokets are reated in the onrete. Voids an be aused by the lak of flow around obstales suh as ties, rebar and blokouts within these rigid form types. Air also may be trapped during the pour. DSF ICF does not require vibration when you follow DSF reommended appliation proedures. The Diamond Snap- Tie is designed to allow 4-6 slump onrete, with 3/4 or smaller aggregate to readily flow around and through the tie. The Diamond Snap-Tie design, along with the natural vibration that takes plae in the form system during the onrete plaement, eliminates the need for additional vibration. The natural vibration aused by the onrete plaement eliminates voids and honey-ombing in the DSF ICF System wall. Diamond Snap-Form has evaluated in-plae DSF ICF walls to prove that onsolidation does our. Blok-outs have been removed and the Foam-Control EPS with Perform Guard stripped from the projets. Eah of these appliations showed exellent onsolidation of the onrete. To further demonstrate that omplete onsolidation ours around the Diamond Snap-Ties, a onrete saw was used to ut through a typial 8 DSF wall. The ut was made diretly in line with a row of Snap-Ties. It was found that onrete had flowed through and ompletely around the Diamond Snap-Ties. Consolidation was so omplete that the printing found on the web of the tie was embossed into the onrete and legible. Copyright 2011

7 7007 ICF Diamond Snap-Tie Alkalinity Resistane Any time produts are used in onjuntion with onrete, the produt is subjeted to an alkaline environment. This alkaline environment has a tendeny to slowly deteriorate many materials over time. Diamond Snap-Ties are enased in onrete, and these ties must ontinue to withstand potential alkalie exposure. DSF ICF polymer is resistant to many hemials, inluding alkalies. The Diamond Snap-Tie is manufatured from polypropylene homopolymer and produed under a strit quality ontrol program. Through utilization of this high quality, alkalie resistant polymer, DSF knows that its Diamond Snap- Ties will perform unaffeted in onrete. Copyright 2011

8 7008 Rebar Requirements and Diamond Snap-Form ICF System Conrete walls an be lassified as either plain onrete or reinfored onrete. The Amerian Conrete Institute (ACI) defines plain onrete as onrete that is either unreinfored or ontains less reinforement that the minimum amount speified in the ode for reinfored onrete. Reinfored onrete is defined as onrete reinfored with no less than the minimum amount required by the ode, and designed on the same assumption that the two materials at together in resisting fore. ACI also states that reinforement shall be aurately plaed, adequately supported and be seured against displaement at the time of the onrete pour, within toleranes of the ode. In typial reinfored onrete walls, the horizontal and vertial rebar is seured against displaement by wire tying the rebar and by the use of spaers. When building with the DSF ICF System these methods of seuring the rebar are not neessary. The Diamond Snap-Tie has a rebar radle into whih the horizontal reinforement is plaed. This seures the rebar in plae. The positioning of the rebar radle also ensures that the onrete over is a minimum of 1 1/2 inhes. Vertial rebar is aptured between the webs of several Diamond Snap-Ties. The frition developed from plaement of the vertial rebar keeps it in plae when the onrete is poured. When designing reinforement for the DSF ICF System, it is most effiient to keep the spaing of the horizontal and vertial reinforing to multiples of 12 inhes, sine the Diamond Snap-Ties are spaed at 12 inhes on enter in eah diretion. This spaing of reinforing will allow the Diamond Snap-Ties to seure the rebar against any displaement and not require any time onsuming wire tying of the rebar. Copyright 2011

9 7009 Sound Transmission of Conrete Walls The Diamond Snap-Form ICF System is often used in above grade appliations. Many of these appliations, inluding exterior and partition walls of ommerial strutures, require that speifi sound transmission standards be met. These requirements are usually alled out for in a speifiation as a STC value. STC (sound transmission lass) is determined by testing full sale wall assemblies for the amount of sound whih transmits through the assembly at various frequenies. The following are STC Values for onrete wall assemblies whih onsist of plain onrete (no insulation attahed): Conrete wall thikness STC* * STC values extrated from Portland Cement Assoiation paper, Sound Loss Through Conrete and Masonry Walls, by Albert Litvin and Harold Belliston. These STC values typially will meet or exeed speifi sound transmission requirements found in most strutures. STC values will also be enhaned when additional finishes, suh as drywall and/or ementitious oatings, are added to the final wall assembly. Please onsult with the Portland Cement Assoiation, as well as other appropriate resoures, regarding onrete design. DSF ICF wall appliations provide exellent sound resistane and will meet most speifiations found in ommerial and ommon wall strutures. Design of final appliation to meet STC requirements is the responsibility of the building designer. Copyright 2011

10 & Greater Diamond Snap-Form ICF Appliations The DSF ICF System is available with ties that reate 6, 8 and 10 onrete wall assemblies. In a small perentage of appliations a greater thikness of onrete may be desired. Diamond Snap-Form has developed a ost effetive means for reating a form system that will allow for walls of 16 and greater. The following hart shows tie ombinations and the resulting onrete thikness of the wall. Tie ombination = Wall Thikness When ties are ombined to fabriate ties for these larger wall setions, it is neessary to attah the ties to eah other with four # 6 ourse threaded drywall srews. Care must be taken not to over torque the srews. Thik wall setions, suh as those listed above, are not to be poured in lifts greater than two feet per pass. Copyright 2011

11 7011 Conrete Plaement Diamond Snap-Form ICF The following reommendations are intended to help you suessfully pour your DSF ICF wall. First and foremost, shedule the onrete to arrive only after your DSF ICF system is ompletely in plae and you have time to double hek your details. Be sure to plan ahead when ordering pump truks and onrete. Allow time for the equipment and onrete suppliers to shedule your delivery. Conrete truks hold at most 10 ubi yards of onrete and most suppliers allow 5 to 7 minutes per yard of onrete to unload. Ask the ready mix supplier to spae the onrete truks out appropriately for your projet. A pump truk will retain about 1 ubi yard of onrete in its hopper and line. If you annot hand haul this to the ICF wall, it will be dumped in leanup. To be sure you have an adequate quantity of onrete ordered, it is best to give your ready mix ompany your wall dimensions, and let them tell you how muh onrete you should order. In this way, any wastage fator beomes their responsibility and should be taken into a aount by them. When you are pouring onrete into the DSF ICF system, diret the onrete stream between the Diamond Snap-Ties as you move down the wall. Always pour onrete at a ontrolled rate. Pouring should be done in 4 foot maximum lifts in a ontinuous pour around the DSF ICF wall. Normal onrete mix for a DSF ICF wall is 5 slump with maximum 3/4 ut aggregate. However, design and/or ode requirements ould possibly ditate a different onrete mix. When ordering onrete explain to the ready mix supplier and pump truk ontrator that you are pouring an ICF system. Tell the pump truk supplier that you want two 90 degree elbows or an S attahment for the end of the pump hose. Elbows and S attahments help ontrol the disharge of the onrete from the delivery hose. If you an get a pump truk that is a newer model with an aumulator on it, request this from the pump truk supplier. Copyright 2011

12 7012 Use of EIFS Type Systems over Diamond Snap-Form ICF The DSF ICF System onsists of a uniquely designed plasti tension tie and high density Foam-Control EPS with Perform Guard insulation. These omponents are used to reate a lightweight rigid form, into whih onrete is poured, resulting in a high strength insulated onrete wall system. The DSF ICF System has been used widely in building foundations, above grade walls, retaining walls and other similar strutures. DSF feels that EIFS produts are an exeptional finish for the DSF ICF System. We have developed details whih show the appliation of EIFS systems. We are providing these to users of the DSF ICF System, so that they have a basi understanding of the methods for applying EIFS Systems and One Coat Stuo produts. Complete installation guidelines for EIFS Systems should be obtained from the EIFS ompany. The reommended guidelines, as warranted by the EIFS manufaturer, are reognized as the primary soure of installation information for the EIFS System. Our reommendations are general and show the two basi approahes for the appliation of EIFS and One Coat Stuo Systems over the DSF ICF System: Polymer Based Systems - DSF suggests that a minimum layer of 3/4 EPS be applied over the ICF System. Attahment an be made by EPS foam to EPS foam adhesive bonding methods that are reommended by the EIFS manufaturer. Attahment an also be made by srew fasteners into the Diamond Snap-Tie fae, as reommended by the EIFS manufaturer. The finish system an then be applied per the EIFS manufaturer s guidelines. Expansion joints should be installed where substrate hanges our, or at a frequeny reommended by the Polymer Based EIFS manufaturer. Polymer Modified Systems - DSF suggests that these systems an be applied diretly to the ICF System, provided that the DSF ICF substrate has been rasped to a level plane, and that a reinforing mesh reommended by the EIFS manufaturer is used. The reinforing mesh should be srew applied to the fae of the Diamond Snap-Tie, with the polymer modified reinfored oating then applied at a level fully embedding the mesh and overing the fae of the Diamond Snap-Tie plate at a minimum thikness reommended by the Polymer Modified EIFS manufaturer. Finish oloring, when required, should be applied per the EIFS manufaturer s guidelines. Expansion joints should be installed where substrate hanges our or at a frequeny reommended by the Polymer Modified EIFS manufaturer. One Coat Stuo Systems - DSF suggests that these systems an be diretly applied to the DSF System provided that the DSF substrate has been rasped to a level plane, and that a reinforing wire reommended by the one oat stuo manufaturer is used. The reinforing wire should be srew applied to the fae of the Diamond Snap-Tie with the one oat stuo then applied at a level fully embedding the wire reinforement and overing the fae of the Diamond Snap- Tie plate at a minimum thikness reommended by the one oat stuo manufaturer. Finish oloring, when required, should be applied per the one oat stuo manufaturer s guidelines. Expansion joints should be installed at a frequeny reommended by the one oat stuo manufaturer. Copyright 2011

13 7013 Windspeed versus Pressure - Diamond Snap-Form ICF Diamond Snap-Form (DSF) ICF reommends the following formula be used in order to alulate the approximate load that will be imposed on a DSF formed onrete wall for a speifi windspeed: The following formula and graph are based upon atmospheri pressure of 14.7, a temperature of 60 o F and a veloity pressure based on air whih is lbs/ft 3. Atual values will vary with elevation, atmospheri onditions and geographi loation. The formula for approximating veloity pressure is p= w 2 or the onstant of X the windspeed squared. A qualified engineer should be onsulted to ensure adequate design of the onrete wall. 120 WINDSPEED vs. PRESSURE pressure, psf windspeed, mph Copyright 2011