Carolina X Wall: The X Factor in Green Building

Onward and upward!

2010-09-22T18:36:00.001-07:00

We are thrilled to announce the launch of our new website and blog! There will no longer be posts at this site, so move on over and follow along at http://carolinaxwall.com/blog/. You can subscribe to the blog via RSS in the right sidebar there. You'll find the same great commentary and information in a new uniform, easier to navigate format. And, check out the new homepage as well, at www.carolinaxwall.com. Let us know what you think!

ARXX goes BIM!

2010-09-17T11:31:00.000-07:00

Understanding Building Information Modeling (BIM)

Building information modeling is an integrated process built on coordinated, reliable information about a project from design through construction and into operations. With BIM, design professionals are able to work collaboratively using models created from consistent and reliable design information.

Click here to access the ARXX ICF BIM models on Autodesk Seek. BIM covers geometry, spatial relationships, geographic information, quantities and properties of building materials and components. It can therefore be used to demonstrate not only the entire building lifecycle, but also the impacts the building and its component materials have on the environment.

By adopting BIM, architects, engineers, contractors and owners can easily:

Create coordinated digital design information and documentation.
Use that information to more accurately visualize, simulate and analyze performance, appearance and cost.
Deliver the project faster, more economically, and with the potential for reduced environmental impact.
Make faster and better decisions.
Predict the buildings performance characteristics before breaking ground.
Create drawings and details directly from a model (and have the software automatically coordinate these drawings and details with the model).
Improve efficiency and accuracy of green certification.
Obtain schedules of building material quantities to determine the percentages of material reuse, recycling and salvage.
Utilize advanced visualization techniques for solar studies.
Improve collaborative communication among various stakeholders (architect, owner, consultants, review bodies, builder, etc.)

With BIM, much of the data needed to support performance analysis is captured naturally as design proceeds. BIM allows design professionals to analyze how a building will perform, even in the early stages of design. Armed with this information, design professionals can evaluate design alternatives quickly and make better decisions for greener more energy efficient designs. By streamlining design and analysis, BIM facilitates the calculations needed to optimize building performance.

ARXX Insulating Concrete Forms and BIM

As industry methods evolve to meet the increasing complexity and multiple requirements for information and data related to construction, sustainable design and building life cycle analysis, it’s important that ARXX leads the way with the tools necessary to make designing and building with ARXX ICFs easy and efficient.

ARXX has created over 120 combinations of parametric 3D model details of standard ARXX Edge, Prime and Steel ICFs and applied a variety of common exterior and interior wall finishes. Design professionals now have the necessary product information and specifications for ARXX products at their finger tips. Some of the information readily available through BIM about ARXX products and wall assemblies include:

Size – length , width, height, EPS thickness
Volume
Clear R value
Wall assembly U Value - minimum
Fire Resistance rating
Sound attenuation rating - minimum
Form weight

All of the ARXX BIM files are available through Autodesk® Seek. Autodesk is the industry leading online source for building product information that allows design professionals to search, select and specify the best building materials for their projects such as ARXX insulating concrete forms. ARXX ICF products have been developed as a family of 3D details for Autodesk Revit® software versions 2009 and 2010. The RVT, DWG, DWF and DXF files are all available for download including any relevant marketing and specification materials.

To watch an ARXX BIM demonstration video(wmv file, 16MB)* click here.

If you have any questions about ARXX BIM files, contact our technical support team at 1.800.293.3210 x 5 or techsupport@arxx.com. We’re here to help.

Click here to access the ARXX ICF BIM models on Autodesk Seek.

Pour Day 8-Gable Ends

2010-09-09T19:10:00.001-07:00

This pour was a bit of a challenge at first because of the hose selection, a 3 inch hose with a bit of a curve on the end. That presents a tall task to the hose man, who has to muscle with two hands to point the hose into the wall rather than to easily guide the hose with one hand. It's especially key to make sure the proper selection is made when you have more dangerous scaffolding applications, like the tall wall setting here. It's just as important to make sure that the pump driver is on the same page. It is no fun to be 15 feet in the air with a boom shifting around while trying to point a curved hose in the proper direction. Once the 3-inch hose was replaced with a 2.5 inch one that was clearly more straight and flexible, life got exceedingly easier for the entire crew.

Because of the hose selection, and the subsequent delays in process, there were several close calls with the concrete truck "on deck" (to borrow a term from baseball) potentially needing to be sent back to the plant.

Manning the 3-inch hose required much harder work.

Going up gables required more coordination as the hose needed to be past from one worker to another on different sections of scaffolding.

Pump drivers need a delicate touch. Just millimeters on the joystick can mean feet at the end of the hose. It's easy to tell a good driver from a not-so-good one. ICF experience is a most helpful asset, and it's not a great idea for an inexperienced one to learn on a project this size.

People, professionals and laypersons alike, often question the capability of shaping wet concrete in sloped applications. These gables are on a 12/12 pitch, a full 45 degree angle, and as you can see, there was no problem troweling the mix to the peak.

The third story of ICFs fully complete, the project awaits masonry and hollow core planks before the final stretch of 4th story walls are assembled. Once again, the ICF crew of 10 workers has outpaced other trades. Who doesn't want a more complete system that goes up faster with less people and less subs?

Scaffolding Comparison

2010-09-01T06:46:00.001-07:00

We've already mentioned the difference in labor force required to put up different assemblies. With ICFs, fewer people install more components of a better wall assembly in one simple step. Part of the reason for that is an integrated bracing and scaffolding system. Take a look at these pictures which show how much work space remains with ICF scaffolding in place, compared to traditional scaffolding required for other assemblies. Because only nine pound blocks are installed from ICF scaffolding, and, at most, 20 foot lengths of rebar, a more streamlined system meets needs.

Here you can see even tall wall ICF bracing in place. Traditional scaffolding pieces on the ground are about to be assembled.

This photo and the next one compare up close the difference in complexity of the two systems. It saves a lot of time and labor utilizing ICF bracing.

Compare this shot to the first one.

Up with the Gable Ends!

2010-08-19T12:49:00.001-07:00

It is truly exciting to see the building taking its form! I can't stress enough how much a quality installer plays into the success of the build. The tightness of the site, the challenge of scheduling trades, meeting demands from different angles. Robbie Vernelson of RDV Contracting and Humberto Mendieta of ICF Construction have made a remarkable partnership. And the commitment and morale of their crew is to be commended. These are quality workers who know how to make a project move quickly, giving thorough attention to detail, all while adjusting to the expected and unexpected events on a busy job site.

The procedure for assembling a gable end, in order to ensure proper dimensions and alignment without endangering workers by needing to cut high up in the air, involves "dry-stacking" the forms on the floor first. This especially helpful because of the louvered openings in four of the eight gables on the building. Follow along here for a brief sequence of assembly.

Forms are numbered so that, once cuts are made and pieces are separated in order to pass up the scaffolding, they will be stacked in the appropriate order on top of the wall.

Each form with an angles chalk line will be brought down and cut on the ground. Safer, faster, more accurate.

With these ARXX Steel ICFs, the hole for the louvered openings is simply cut out with a reciprocating saw.

The special round buck by V-Buck is made to order, right to rough opening size, and conveniently fills the spot cut for it without a worker needing to lift a saw.

3rd Story Progress Video Clip...

2010-08-11T06:57:00.000-07:00

New Project Profile at ARXX.com!

2010-08-05T11:47:00.000-07:00

Click here to view:

Project Gallery: Chidley North Residence Hall

Pour Day 7 - Video

2010-08-05T07:01:00.000-07:00

Pour Day 7 - Second Floor complete

2010-08-04T08:58:00.000-07:00

RDV Contracting owner, Robbie Vernelson, monitors progress. RDV's crew consists of nine to 10 workers.

Jeff Philips of InFocus Design Studios shoots some footage of the pour. It could be pointed out here that he seemed to be wondering, "What's the big deal?" concerning pour day. That's a great question. When you have a crew and a pour team (including the concrete supplier and the pump truck operator) that know what they are doing and have a good working relationship on site, pour day is indeed quite uneventful. So, while the film may not be that exciting, that's precisely the point. We've dispelled some pretty big rumors and assumptions about ICFs as a result. In fact, the project engineer's inspector and assistant superintendent, were catching up on something clearly other than the pour down on the ground while the pour was taking place two stories up. On the first pour, the inspector was there every step of the way...up on the scaffolding, right by the hose!

Perfecting the plumb of the wall once concrete is screeded at the top.

Steel beam pocket is packed tightly and trowled by hand.

One more partial story (7' plus) of ICF on this wing. The roof system will extend from that point and include 10' dormer windows.

The "core" of the building, parallel to the concrete truck here, will rise two more stories.

Lord Aeck and Sargent, Architect Discusses ICF and Green Building Features

2010-07-29T09:06:00.001-07:00

Derek West and Sarah Weiser, of Lord Aeck and Sargent, Architect, discuss features of a residence hall project, including the selection of ICFs for the project.

Introduction to ICFs - USGBC Talk-n-Walk - Durham, NC

2010-07-29T07:38:00.000-07:00

Bradley Yoder, President of Carolina X Wall, introduces insulating concrete forms to two dozen USGBC members on site in Durham, NC.

Hollow Core installation/integration

2010-07-27T10:30:00.000-07:00

Here are some photos of hollow core installation taking place this morning before the rain came.

Notice here that the rebar used to tie the floor system into the wall is a 90º rebar that turns up rather than down into the wall. This makes the placement of this reinforcement far more simple than if it were required to come up out of the lower level wall. It is nearly impossible to either bend the rebar precisely in between planks being laid, or to navigate the planks into place around a fixed piece of rebar. There is almost no way of knowing the layout of the planks and placing the rebar appropriately according to that layout beforehand, so simply installing them when the grout between planks is placed makes for much faster assembly.

USGBC Talk-n-Walk

2010-07-22T09:04:00.000-07:00

Yesterday evening we had the privilege of welcoming the local chapter of USGBC and Triangle AIA COTE (Committee on the Environment) to our residence hall project to introduce them to ICF construction, and to hear firsthand from the architects why they selected the product for this application. Great turnout, good questions, some good wheels turning. The session was videotaped, so keep an eye out for that once our new website is launched in the coming weeks.

Progress: Post-pour day #6

2010-07-20T10:51:00.000-07:00

Over halfway through the project! Here are some overall project photos.

Hollow Core Details

2010-07-19T07:09:00.001-07:00

Flashback to the rebar schedule on the perimeter haunch for hollow core bearing...

This is what enables the shallow lintels across the window and door openings to carry the heavy load of the precast hollow core floor planks.

Three systems come together here: ICF, masonry walls, hollow core planks. Four, really, with the Z-pan for the hallway floor.

V-Buck

2010-07-16T12:12:00.000-07:00

ICFs are great, a simple way to form concrete, with added benefits of insulation and attachment points. If all you had to do was build a wall, no problem at all (with any system, really). But, of course, you have to get in the building, through doors, and it's nice to be able to see out of it once your in it, with windows. So how to easily block out for openings? While some options involve using pressure treated lumber, some of the issues that come along with those methods are less than favorable: moisture absorption, warping and bowing in weather changes, variability in dimensions from piece to piece. One of the best ways to beat those issues is with V-Buck, a 100% recycled vinyl product designed just for ICFs. It comes in widths designed to fit around conventional ICF form widths, and creates a clean, uniform substrate to which other materials can be fastened. And it is not subject to degradation over time, as wood can be. See it in action below.

For a project of this size, with little storage space on site, V-Buck was able to precut most of the pieces. Less to cut on site means a safer, faster installation process.

Special round openings for the functional louvers in the gable ends of the building were made to order as well. V-Buck offers many different special shapes.

Integrated flanges seal around the ends of the form work to create a clean junction between the two materials.

V-Buck provided an easy way to create end caps for the end walls in this design.

Bucks are often assembled and squared on the ground prior to installation in the wall. What's great about V-Buck is that it is light enough to do this safely and easily. With a wood buck, much more wood than that which actually stays in the wall is required to shore up the buck.

Pre-cut pieces marked and ready to build.

Hollow Core Planks

2010-06-21T13:13:00.001-07:00

You can specify and integrate any commonly used floor system with ICF walls. It all depends on the needs of the project. While there are ICF floor systems, hollow core planks were utilized here for their slim profile, only 10", including 8" planks and 2" topping of concrete. It was also selected for speed.

Utility Penetrations Are Easy...

2010-06-17T06:33:00.000-07:00

...if timed correctly! It's not always a matter of simply removing foam. It is with the smaller penetrations, but this building has some big ones, which means removing some of the ties in the forms.

These special made utility sleeves have a water stop ring that sets inside the form.

A large enough hole must be cut on one side of the forms in order for the water stop ring to fit in.

Then, it sits flush against the inside face of the other side of the form.

The forms here are reinforced with OSB screwed to the ties and foam glued around the opening to seal if for concrete placement.

Liquid concrete consolidates well even around tightly arranged small openings.

This bank of electrical conduit comes through the ICF wall (below).

Joints are prepared with waterproofing ahead of time, before the overall coat is applied.

Prefab rebar

2010-06-07T11:37:00.000-07:00

I helped build many homes with PolySteel ICFs up in Harrisonburg, VA with Glen Stoltzfus Builders, and Virginia PolySteel, and we always had to bend and cut our own rebar to fit our needs. For such a large and intricate project as this residence hall, pretty well the only cutting that needs to take place are for the proper length of straight pieces. All bending and cutting and bending of stirrups, corners, and other unique pieces is done by Rockingham Steel at their facility. What many folks don't realize is that rebar fabricators will do the same even for residential projects. Make sure to inquire where you source your rebar.

Similar Project in Ethiopia (though not ICF)

2010-06-07T11:14:00.000-07:00

I thought this would be an interesting comparison. My folks were in Ethiopia last year and got to witness the construction of a new dormitory on the campus of an institution there. We are so dependent upon technology, so it's amazing to see what can be done with two very standard pieces of power equipment, and a bunch of people. Granted, time is a different story there... Enjoy!

Getting gravel to the mixer.

All concrete for this entire project mixed in a mortar mixer.

The mortar mixer and hoist are the only power equipment utilized, and even the latter was only used when the ramp (see below) was out of reach of the very top of the building.

Concrete bucket hoisted up through the intricate scaffolding assembly.

Would you wheelbarrow a full load of concrete up this ramp...barefoot?

This man and woman haul concrete up the scaffold ramp at a nearby building.

The entire structure is reinforced concrete alone. It will be infilled with handmade concrete blocks (below).

Hand made cinder blocks laid out to dry.

Each cast-in-place slab is shored up with small tree trunks.

Central triangular atrium.

This dormitory will house 400 students, just a few less than our project in Durham.

Pour Day 2

2010-06-04T08:21:00.000-07:00

Pour day pictures are pretty self explanatory. But, they amaze me every time. What we're able to do in a matter of a handful of hours, without too much exertion, is remarkable with pump and concrete truck technology. In contrast, consider a building in Ethiopia my folks saw under construction last year during a visit. As soon as I get the photos and details from them, I'll post them, too. For now, enjoy these shots of a well-orchestrated pour day...

Perimeter Bearing Haunch

2010-05-25T11:59:00.000-07:00

Whenever a new building system is encountered by designers and engineers, the most frequent question is, "How do we do this?" followed by, "Then, how do we do that?" This project was no exception, the biggest question being about how to integrate hollow core planks for a trim floor system depth with only 8"or 6" of concrete thickness on which to bear the planks on the ICF perimeter wall. That was a mouthful...but the answer is not. Just like the foam was easily manipulated to provide for integrated brick ledges and pilasters (in previous posts), the forms shown here have been altered to allow for two and a half more inches of concrete bearing surface.

About 18" of the inside panel on the top course of forms was removed. This process involves placing the last course without glue, numbering them in sequence, establishing the height of the necessary cut at each corner of the building, then chalking lines on the walls between those marks. The forms are then brought back down and cut along those lines, then glued and returned to their numbered position on the wall.

A portion of each metal tie is left on the form so that concrete will hold fast to it.

This wider angle shot helps establish the perspective for the next photo. Here you can see how plywood has been fastened to the inside surface of the forms reaching up beyond the edge of the foam to allow for the concrete to come out to the surface of the foam.

A good string line makes a good straight wall. This string line will be used to make final adjustments to straighten the wall right up to the last drop of concrete on pour day.

A little closer and different angle photo here shows the intense schedule of rebar stirrups prescribed for the bearing conditions of the coming hollow core planks.

The formwork includes the integration of laser-leveled OSB strips to ensure that the height of the entire perimeter of the wall is consistent and uniform.

A smooth enough surface for the hollow core planks is screeded at the end of pour day. If you look closely, you can see that the bracing (the vertical aluminum pieces) is used to form the concrete as well, so that they did not have to be furred out to account for the thickness of the OSB forms.

Pour day, interestingly enough, is one of more uneventful days of an ICF install...if everything has been executed well. That was certainly the case here. Duties are assigned to the workers in order of priority so that if a louder voice calls, a quick shift to the needed spot is made and the pour can continue smoothly. A hundred and twenty-four yards of concrete were poured in six hours, and after tweaking, straightening and screeding, the crew got the rest of the afternoon off...while the concrete carried on the work as it cured.

If you can't see the care and attention that was given to this assembly, you're not paying attention. The precision execution from footing to float (screeding at the top of the wall) is evident in the uniform consolidation of the concrete, the straight walls, and accurate placement of rebar. There is a night and day difference between a crew who is familiar with ICFs, and one that is learning.

Bracing and formwork is removed to allow work to continue the day after the pour.

I am curious to hear the assessment of the haunch by the hollow core installation crew, because it sure seems like it will be smooth sailing from where I stand.

Integrated Pilasters

2010-05-25T07:33:00.000-07:00

Sometimes folks new to ICFs are really confused when they see foam forms. They know the foam can't be the structure of the wall, but are sometimes embarrassed to ask. Once they hear what the space in the middle of the forms is for, or they see a finished assembly with the concrete inside, it all makes sense. One of the biggest lessons in ICF education is the realization that not only are the forms simply that, forms for concrete, but the reinforced, cast-in-place assembly is structurally second to none, and that a properly engineered and quality-controlled ICF product is plenty strong to handle the demands of placing concrete. Any compromise (a.k.a. blowout) of the forms is more likely to take place where a form has been cut, or near an opening, rather than in a running section of wall, and these happen less and less frequently as the industry and the products mature. In other words, installers are aware of the weaknesses, and account for them with additional shoring where appropriate.

A simple detail afforded by the flexible nature of ICF forms is the integrated pilaster. While the thickness of the concrete inside the forms in the assembly shown here is 8", 2.5" of foam on either side provides potential increased thickness of the concrete structure which, with additional reinforcement, can provide a stronger structural member (a pilaster) without needing to bring the concrete proud (beyond the plane) of the surfaces of the forms.

OSB forming, bolstered by lumber and steel tie wire, makes integrating pilasters a simple process.

It can take a little bit to orient yourself to the perspective of this photo. You are looking down the surface of the wall to show how foam was removed and the wood form is placed on the outside plane of the form. This, additionally, provides a much easier way to install the rebar cage specified.

This is an even wider pilaster.

Here, you can see each of these pilasters with the concrete set and forms removed. Placed in the the pockets at the top of each pilaster are embed plates, onto which steel beams will be placed.

In this photo, again, looking down the surface of the wall, you can see the corner of the steel embed plate, onto which a steel beam will be welded for an element of the structure that extends beyond the wall surface. This plate was placed in the wet concrete on pour day. Notice how the concrete and surface of the forms are in the same plane.

Once sheetrock is placed on the forms, no one will realize that this pilaster is present, providing a cleaner, uninterrupted surface likely not otherwise possible with a different wall assembly.

Integrated Brick Ledge a simple step with ICFs

2010-05-21T12:17:00.000-07:00

Once again, we're dealing with EPS, expanded polystyrene, easily manipulated with simple tools like the handsaw or a key hole saw. This makes the system flexible in its structural capacity, since we can shape forms and add reinforcement for liquid concrete to conform to our designs. Read further for a walkthrough of the brick ledge process.

Holes are simply carved between the steel ties with a hand saw. The steel ties remain intact for form strength while allowing a place for reinforcement and concrete to reach out of the formwork.

These are specially bent rebar called stirrups, prescribed by the project engineer, which are fastened to the 12" on center vertical rebar. They connect the ledge, on which two and a half stories of brick will rest, to the 8" concrete wall inside the forms making a monolithic structure.

During concrete placement the, in this case, second lift was stopped at the height of the ledge to allow consolidation (here mildly assisted by a concrete vibrator) without spilling concrete. You can see how clean the form work is, a testimony to the care required, and employed, by the pump operator and hose man.

Since we're not dealing with a finish surface, the extent of the detailing is what you see here.

Removal of the formwork...

Reveals a clean, effective ledge which will eliminate the need for many hundreds of square feet of masonry which would otherwise be need to run all the way down to the footings.

Form work is easily provide around corners, and at various heights.

North Wing Progress

2010-05-14T08:49:00.000-07:00

One of the challenges with any project of this size is coordinating each trade so that prerequisite work is completed in a timely fashion to make sure the project can progress smoothly. You can see in these progress shots that while the ICF phase is under way, digging for more footings and plumbing is also taking place, even on pour day! It will really start to get interesting once the hollow core planks come on site for the floor systems. Coordinating their installation, with the masons for the interior walls (and there are a lot...this is a residence hall after all!), ICF for exterior walls, plumbing, and electrical, among others, will be a fascinating exercise.

Bracing ICF Walls

2010-05-14T07:19:00.001-07:00

One of the most frequent comments I've received while walking this site with folks new to ICFs is, "That bracing system is slick!", or something to that effect. Indeed it is. The fraction of its weight and complexity compared to traditional forms and bracing, and the lesser amount of space to store and transport these materials is no small thing when comparing cast-in-place concrete systems. I've mentioned it before, but it deserves some more attention, that the form work being (or becoming) the insulation for the wall means we have a system instead of an individual component, several critical features built into one step. Concise and complete ICF bracing systems facilitate the simplicity of the assembly process.

The brand used here is called ReechCraft, and consists of 4 components. Above are, from the top, walk board attachments, diagonals/turnbuckles, and hand rail attachments.

Here, the lightweight aluminum "strong-backs" are stacked.

A "strong-back" with a 4 ft. extension for the taller wall application pictured in some following photos.

The bracing system during assembly. Walk boards and hand rails are not yet installed.

The 4' extensions enable taller wall applications, such as this 15' plus section here, the sunken area for the chiller room, where larger mechanical equipment will be located.

The integrated walk board provides a safe, OSHA-approved scaffolding in addition to its bracing and straightening capabilities.

Here, this worker is measuring the space between the string line, which is to be an established distance from the wall surface, and the wall, (in this case inside the bracing, for consistency, as there is plywood forming in between). He relays the information to the worker on the ground...

...who turns the turnbuckle clockwise to bring the wall closer, or counterclockwise to push the wall out. These finer adjustments are often made while the wet concrete is in the wall. The force of concrete placement can often negate incremental adjustments on such a fine scale (1/8" to 1/16"), so tweaking precisely prior to the pour is lost time.

Stacking ARXX Steel Blocks

2010-05-12T18:57:00.000-07:00

Legos® get lots of air time when describing the simplicity of stacking ICF forms. With ARXX Steel forms, the interlock between adjacent blocks is provided by tongues and grooves. All ICF forms require some method of holding forms together, clips or snaps or the like. In ARXX Steel's case, foam glue is used in the grooves (bottom of the form) of a loose form before fastening it to the wall assembly. This foam glue is extremely strong so that after just a few minutes, you will not be able to separate the forms without physically cutting them apart. This provides strength and resilience during the concrete pour. Maybe an even more important benefit is that the combination of glue with the tongue and groove feature provides resistance to deflection, or settling of the forms during concrete placement. ARXX Steel forms retain their assembled height, and on a building with critical dimensions (what building isn't?) this is key. A ten foot floor to floor height is sacred, no room for squashing the forms to 9' 11 1/2".

Glue applied in each groove (about a 1/4 to 3/8" bead)...

A two man team can really speed up the process. While one is placing the form in the wall, the other glues the next block which is ready when the first block is set.

These blocks were going in at a rate of about 1 every 30 seconds. Granted, with an intense reinforcement schedule and unique form cutting such as utilized on this project, stretches of speedy stacking are frequently interrupted to allow for prescribed rebar placement. With a 10-person crew, this full wall assembly is installing (from footer to concrete pour--stacking, rebar, bracing, buck assembly and placement, concrete placement) at a rate of about 80 forms per day, or 8 forms per person per day. The kicker is that these walls do not require the additional man-hours to insulate, fur out, or wrap the wall assembly. It is a complete, finish ready system.

Another interesting fact about this ICF building -- It will have about 50,000 square feet of ICF wall. But, because of the cast-in-place nature of the assembly, the building will consist of only 30-35 single panels of monolithic concrete. So the average size of each unique structural section is about 1500 square feet!

Preparing the footing

2010-05-11T19:06:00.000-07:00

A little rain and a week or two can clutter a perfectly good footer.

A little housekeeping...

...and they're ready for chalk lines.

"Pocket" laser levels are handy tools. It's hard to see, but the orange string near the top of the picture is a section line sighted by the builder, used to establish critical dimensions of the building. The laser level helps transfer this section line down to the surface of the footing with ease.

Then, it's just a matter of marking dimensions of the forms...

...and snapping chalk lines.

Moving ICFs on the job site

2010-05-11T18:47:00.000-07:00

While it takes four people to move these bundles around, you have to think about some other numbers. They are moving 128 square feet of wall surface area. This is equivalent to more than 143 cinderblocks, which in turn would weigh about 4170 pounds. How many people would it take to carry those? A forklift. The ARXX Steel forms these workers are carrying weigh just 128 pounds...total.

Four people can maneuver in tight spaces or varied grading more easily than heavy machinery.

Arranging the material in this way would be quite a challenge on this job site with a forklift. And, because each block weighs just 8 lbs, the job site can be a safer place for workers as they navigate the terrain and scaffolding with these lightweight materials.

Waterstop

2010-05-01T04:23:00.000-07:00

A challenge in any concrete wall application is preventing water from penetrating the assembly. The biggest liability is the cold joint between the footing and the cast-in-place wall. To best address this issue, the architect specified a combination of liquid adhesive and a spongy material applied to the adhesive. The material is designed to expand when it absorbs water. When concrete is cast over top of the waterstop, it creates a tight space that will not allow the waterstop to grow, so its expansion actually tightens the space creating a self-sealing effect, and therefore preventing water from slipping into the building.

Applying the liquid adhesive.

A keyway in the footing, a structural feature for the concrete wall to be placed, is an ideal place for the waterstop to be installed.

The spongy waterstop installed. When it tries to expand in its confined concrete housing (after the concrete in the wall is cured) it essentially tightens the space creating a self-sealing, water resistant assembly.

Coming out of the ground on schedule with landmark ICF project in Durham, NC.

2010-04-30T12:46:00.000-07:00

Construction began on the largest Insulating Concrete Form building in North Carolina, a 286 room dormitory in Durham, on April 15, 2010. The following pictures illustrate the 10-day period of ICF assembly, reinforcement, bracing, and concrete placement for the South Wing basement portion.

Footings poured and ready for forms.

First course of forms laid out.

Bird's eye view of South Wing basement.

After starting stacking a day late, pour day is right on schedule.

This is the day after the pour. All bracing has been removed making room for other subs, and the crew moves on to the North Wing.

Welcome

2010-04-30T12:23:00.000-07:00

Welcome to Carolina X Wall's Insulating Concrete From blog. Here you will find candid commentary on project progress, system details, designer, builder and owner benefits, and more.