Placing the SCIPS panels – week one.

   Once the FastFoot foundation was completed it was time to move onto the task of erecting the SCIPS panels.  The foundations were either 30 or 36 inches wide, based on structural needs, and twelve inches high.  The structural engineer had specified two rows of rebar dowels, inside the wire of the SCIPS panels, on 16” centers.  The two rows would be staggered in order to maximize the EPS thickness.  Since there is up to eight feet of unbalanced backfill on the north side, tapering off on the east and west, and a lot of windows, the structural engineers have developed a series of pilasters – internal columns with rebar, carved out of the EPS, to transfer loads to the foundation.

Background on the panels:  

   This is a view of the panels as they are in the wire press at GCT.  The panel shown appears to be a PSG panel, which has channels for concrete and is used where additional strength is needed. 

A profile of the panels is here:

Note that the panels have corrugations which allow deeper mortar in portions of the finished wall.

We are using the PSM240 panels.  The dimensions are listed in the table below.

GCT SCIPs Dimensions Guide
PSM - Wall/Roof Single SCIP
Walls and Roofs
SCIP Model	Aprox. EPS Thick. (mm)	Aprox. EPS Thick. (in)	Aprox. Finish Section Thick. w/Conc. (in)
PSM40	39	1.54	4.24
PSP75 Partition	74	2.91	4.95
PSM80	79	3.11	5.81
PSM100	97	3.82	6.52
PSM120	117	4.61	7.31
PSM140	136	5.35	8.05
PSM160	155	6.10	8.80
PSM190	195	7.68	10.38
PSM240	242	9.53	12.23

   Although the EPS is 9.5 inches thick at any point the actual thickness, from the highest point on one side to the highest point on the other, is closer to 10.25 inches.

   Setting the panels involved multiple challenges:

1   1.       Stage all the bracing material and tools
2.       Move the panels
3.       Get the panel vertical and keep supported
4.       Lift it and slide down over dowels
5.       Make sure the panel(s) are level and plumb
6.       Brace
7.       Re-level and re-plumb
8.       Install second row of dowels

9    9.       Complete rebar and pilasters by burning out the foam and dropping rebar into the cavity.

   Moving the panels proved to be a manageable task.  Although bulky, the panels weigh approximately 100 pounds each, according to the workmen on the project.    The first panels, located near the home site, were carried by hand to the work area.  Later on we anticipate that a tractor with forklift blades will be used.  Larry had worked out a method to lift the panels which used short lengths of rebar, pushed through the EPS below a wire, as handles to allow the panels to be hoisted vertically.  The holes left after the rebar is removed can be foamed before the mortar is applied.

   The first panels to be installed were on the north side of the house.  All of the panels on the first course of the north and west sides, as well as most of the east, are 18’10” tall.  There are two shear walls inside the basement that are 11 feet tall.

   After researching the installation process Larry decided that the best way to approach the panel placement was to epoxy the outside row of dowels into place, then lean the panel against them from the inside while pushing it to vertical.  At this point the rebar ‘handles’ could be pushed through the panel and used to lift it and drop it over the dowels.  The panel could be brought close to plumb, then the FabForm brackets and walers could be used to bring it to plumb.  At a later date the dowels could be dropped down between the wire and the foam.  Epoxy would be placed in the holes and the dowels inserted then the rebar for the pilasters would be dropped into the panels.

   The crew consisted of Larry and three workers, with occasional (very occasional) help from the future homeowner. 

The process:

Footers, braces and dowels ready for placement of the first panel:

Moving a panel:

Placing the first panel:

Temporary bracing for the first panel:

   Perfecting the method.  Note that four people can set up the panel:  One to start lifting and then walk the panel up, one (out of the picture) with a 2x4 to push the panel to vertical, one to stabilize the base and one (on the bank) to control the top.

Close-up of dowels and panels:

Close-up of adjustment bracket

Bracing system in use

   The video of the first day of panel placement is here:  

Day 1 video

   Due to a heavy fog overnight the first few minutes are fuzzy but nothing of importance was missed.

   Placing the first panels was an adventure!  Bear in mind that to the best of my knowledge none of us had ever seen a SCIPS panel installed in real life.  Larry had visited job sites where GCT panels were used but they were all past the panel installation stage.  Our project is a bit more complicated than many due to the pilasters:  the dowels are taller than those on most GCT projects.  There were a several lessons learned during the first day:

1.      Eighteen foot panels are tall.  Very tall.  It was clear before the first panel was set that we needed a way to control the top of the panel.  Luckily the first panels were on the north side, which had been excavated, so the crew member with ‘the hook’ was closer to the top of the panel and could control it easier.  A fourteen-foot 2x4 with a hook on the end proved sufficient for the first few panels, until the gap between the foundation and embankment widened.
2.         The wire flanges on the panels provided major headaches.  There were several occasions when the crew would lift the panel high enough to clear the dowels but were unable to drop it because the wire on the panel being placed became tangled with the wire on the panel already in place.  (Note on the diagram above that the wire extends past the panel on the lower left and upper right.  This gives an overlap in the mesh in the back and front to use in tying the panels together with hog rings.)  The solution is to bend the wire before the panel is vertical so that the wire from the two panels doesn’t come into contact.  The crew member controlling the top of the panel also needs to make sure that he keeps it away from the other panel until it is set down over the dowels.
3.    .    Wire at the bottom of the panels, where it is set on the foundation, could also pose problems.  If it is a little longer than the panel then the foam of the panel can’t contact the footer and must be snipped off.  The crew also learned quickly to check this before lifting the panel.
4.        Make sure that you check all dimensions of the wall section after placing a panel.  In the first section the biggest problem was that the top of the wall was leaning away from the starting point in the same plane as the wall, not perpendicular to the wall as one might expect.
5.        Long panels are inherently more unstable than shorter ones.  It appears that panels longer than twelve feet are made of two pieces of EPS.  Although the mesh is welded there is still a small but noticeable hinging effect where the two pieces of foam meet.
6.        Using the Zont/Zuckle bracing system from FabForm was definitely the way to go.  Adjustments to get the panels plumb were easy to achieve with just a drill.  The system can be seen  here

   The installation process was significantly revised the morning of the second day.

   Justin, one of the crew members, spent some time looking at the work that would be required to drop the second row of dowels into place, epoxy them and then drop the long rebar into position.  His recommendation was that we do more work before placing the panels in order to save time later.  Holes for the dowels were widened slightly, to make sure that the dowels would drop into place easier.  The panel was burned out slightly and ten-foot lengths of rebar were wired into place inside the mesh before the panel was moved to the wall.  At first we were doing the rebar on the inside only, where the dowels were not in place.  Later the crew started adding rebar on both sides.  Once the rebar was being added on both sides it was  clear that a better work surface was needed so sawhorses were moved into position  to make it easier to flip the panels.  Finally, the heat gun that we started out using proved to be too slow so we moved to a small butane torch, then a larger torch.  We are still looking for the best way to burn out the foam in order to prep the panels.

   Lessons from the remainder of week one:

1.    We had been warned ahead of time by Alton and Scott not to use too many hog rings until the wall was in the final prep stage for mortar, since one could lock the wall into a monolithic piece before the final adjustments were made.  The solution seems to be tying the panels together, high on the wall, with ½” temporary fencing tape.  It’s easy to cut, holds well when knotted and is easy to remove.  One source is  here

2.    Cutting the panels is more difficult than it might seem.  Cutting the wire is straightforward; it’s getting a good edge on the foam that’s difficult.  Most saws are too flexible and you end up with a wavy cut.  After a lot of trial and error the crew discovered the perfect solution:  a chain saw. Unfortunately it was deemed unacceptable for safety reasons so the latest plan, which is working well, uses chalk lines on both sides.  A Sawzall is now used to cut from each side and then the edge of a saw is used to shave the edges square.

3.    Corners are a pain in the anatomy.  See item #2 above for one reason, plus the bracing is more complicated.  In short sections it’s easy to move the plumb section of the wall to meet the out-of-plumb section rather than the reverse.  One of the tricks to keeping corners aligned is to tie the temporary fencing tape on the outside of the 90-degree angle.

4.    It’s far better to do as much as possible to the panels while they are on the ground.  Burning out the foam and inserting rebar are significantly easier when the top of the panel is not 18 feet up in the air.

5.    When unloading the tractor-trailer from GCT take the time to stack the panels so that the tractor can get close to them.  We had unloaded the truck as quickly as possible; unfortunately this created work later since the crew had to carry panels a longer way.  As mentioned in an earlier post we are very limited on space, however storing panels so they are accessible in the order needed may be possible with future deliveries.

   For those who want to see the full week's work it is here, all 22 minutes of it.