Autism Treatment Center's new facility in San Antonio

Construction for San Antonio’s Autism Treatment Center’s (ATC) new facility received extra helping hands when several building material manufacturers donated their products to the project. Nearly 4,000 sf of Hunter XCI Ply, a composite insulated sheathing system, was donated by Hunter Panels. This gave Stantec, the architecture firm who designed the project, its first go at designing with the system as a part of their commercial wall assembly. Their project architect said it offered a clean surface for the air barrier and was great for the metal panel fasteners. Superintendent Pete Alcoser of Malitz Construction who built the facility shared similar feedback saying, “It worked out very well. The metal panels went up quickly because the entire face of the wall is an attachment point.”

For ATC, the XCI Ply system provided unimpeded continuous insulation – no Z-girts – and an engineered cladding attachment substrate. The fire-treated plywood + XCI polyiso combo is an NFPA 285 champion offering myriad compliant assemblies and approved for types I-V construction. The system installs directly over steel studs taking the place of fiber sheathing boards. Coated glass mat polyiso contributes to the high R-Value per inch at an R-6. In climate zone 2, two inches of polyiso in the exterior cavity used continuously can eliminate the need for interior cavity insulation in most cases (U-Value prescriptive path). It is worth noting, air & water barriers are no longer hidden behind insulation in this wall design, which is a leg-up for AWB inspection and repair. And the consensus among those who have built using XCI Ply say it is the key component in speeding up envelope wall completion.

If you’re near the 1604 loop and Nacogdoches Road in northeast San Antonio, check out the new facility @ 15911 Nacogdoches Road.

Thanks to Hunter Panels (XCI) for contributing their material for a great cause.

- Darren

HK Ties & New Braunfels' Das Rec

Now open for recreation, Das Rec is in motion. This 77,000 sf recreation center in New Braunfels, TX is a great reminder that concrete and aesthetics can play well together. Designers Brinkley Sargent Wiginton of Dallas scored a visual victory blending color, dimension, materials, and a great deal of thought into this facility. Over 35,000 sf of integrally insulated tilt-wall represents a significant portion of the envelope. Soft building materials often do not fare well in the presence of high humidity conditions like indoor pools. The Das Rec pool is of no small size. And at 82 degrees F, humidity is of certain factor. Insulating the large tilt-walls integrally allowed the facility to meet IECC standards while giving the interior and exterior a clean, durable, face. HK Composite ties are there to hold together the concrete on both sides of the insulation layer. 

HKST 50 and HKST 100 ties were used to connect inner and outer concrete wythes together without creating thermal shorts in the assembly and providing the engineering to keep these walls together for the life of the building. Choosing the right system includes accounting for proper tensile, shear, and pull-out strength of the connector ties as well as fire and alkalinity resistance. AC 320 has been the industry standard for this type of wall assembly. All of HKC's ties are tested to this standard. 

It was a fun experience getting to participate in this project. I Hope to see more of these down the road.

- Darren 

XCI CG in the Press - Manor High

Case Study - Manor High

The story behind the story begins with a little digging (click link above). Looking through the wall details on this project I found XPS (extruded polystyrene), a thermoplastic material, detailed behind metal wall panels. I reached out to the architect and setup a meeting. 

To pass a NFPA 285 assembly fire test, XPS has several obstacles when designed in the exterior cavity as the "ci" component. All window and door header details require special, non-standard detailing, involving 4 pcf mineral safing and steel angles to protect the exterior cavity from excessive heat and flame entrance. Visit one of the XPS manufacturer's websites and you should find rough opening details reflecting these requirements. As a thermoplastic material, XPS is pliable when exposed to heat above 160 degrees F and will start to melt just over 200 degrees F. Given exposure to a flame, XPS rigid foam will quickly melt and drip.

Examining NFPA 285 assemblies after they've been through the 30 minute burn test, the results show melted XPS material most prominently at the header but also near the jambs and under the sill when special rough opening detailing is not in place. The thermoplastic XPS has the ability to burn up the wall assembly as well as spread fire down the wall too. When it comes to metal exterior skins, a popular cladding for almost all building types these days, XPS behind the metal wall panels will not pass an NFPA 285 test without sandwiching the insulation between two pieces of gypsum board. Not a practical way to design a wall assembly. In comparison, polyiso has gained in popularity because of its thermal properties (6.0-6.5 R-Value per inch), ease of installation, and its ability to resist fire and heat. 

A thermoset plastic, polyisocyanurate will only char and flake when exposed to a flame source, and will not soften in high heat situations. The physical property differences with polyiso compared to XPS material reflect well for polyiso, especially in NFPA 285 assembly test results. Although considered a combustible, polyiso does not require any special header detailing at rough openings and will pass NFPA 285 tests behind panels used as the exterior skin - without additional gypsum board. Regarding rough openings, the NFPA 285 testing Hunter XCI has had conducted by third-party laboratories has shown that the window framing alone is enough detailing to pass the assembly test. This is a huge testament to polyiso's fire retardancy.

Hunter XCI's CG (coated glass facer) polyiso board, highlighted in the article offers exceptional durability, vapor permeance, and a mile long list of NFPA 285 compliant assemblies which include, of course, assemblies utilizing exterior metal panels. With a similar price point to XPS, a higher R-Value per inch, and no special header detailing, Hunter XCI CG is an easy choice for exterior continuous insulation. The article is case-in-point.

- Darren