The Evolution of Retrofit

By Dale Nelson, Roof Hugger President.

January 2020 marks 29 years since the inception of Roof Hugger.

Wow, time flies! It’s always fascinating to think back on how much Roof Hugger has changed over the years. When my friend and partner Red McConnohie and I started Roof Hugger, our goal was to create something that would allow a new metal roof to be installed over an existing metal roof. It had to work for any new panel, be easy to install, economical and structurally correct. A notched “Zee” seemed to have the most promise. Sounds simple, but there were many challenging issues we had to solve to make Red’s innovative idea a real and marketable product.

There was no accepted test protocol when we started, so together with a local engineering firm and local test lab, we created one. A few years later the E-1592 test protocol for metal panels was adopted, setting a new level of sophistication for all our future tests. Actual in place performance tables were established. New corner and edge zone framing assemblies were created to comply with the updated building codes that divided roofs into several distinct zones not just one uniformly loaded roof area. Construction details had to be changed and standard sizes of our sub-purlins had to be modified. All this was a huge change at the time, affecting all manufacturers and contractors in our industry.

By 2005, a new wrinkle had come into being: the “Green Movement.” Not only did we have to address structural attachment and panel performance but now we had to design and incorporate energy-saving assemblies. We had to design for rigid or fiberglass insulated assemblies and above sheeting ventilation. We had to understand thermal conductivity, thermal breaks, thermal emissivity, thermal reflectivity, solar heat collection and solar power generation. The Roof Hugger Systems had to accommodate specific insulation and mechanical systems while meeting all the structural code requirements.

Once again it was long hours, lots of reading, brainstorming and naturally - more testing. Roof Huggers with ventilation holes were created, new thermal break assembles had to be mated to our retrofit framing system, access openings for solar collection coils were designed, drag loads, and additional dead loads for photovoltaic systems all had to be considered. All this with an eye toward our ultimate critic……the installer. The system had to be as intuitive as possible, use standard tools and fasteners and go down quickly.

Innovative retrofit design work continues today with no end in sight. Roof Hugger’s latest task is to conduct testing that will evaluate how much strength our sub-purlin system adds to the capacity of the existing purlins. Although the codes allow 3 PSF for retrofits, some buildings need additional reinforcement and this testing will identify the extra contribution to purlin strength the Huggers provide.

As I move in the direction of semi-retirement it is great to know our skilled and knowledgeable staff, headed by Red’s grandson and The LSI Group, our new owners, will continue to work tirelessly to maintain Roof Huggers’ leadership in the metal-over-metal retrofit market. As always, we will keep our eyes on the codes and any new technologies that can provide our customers with the best retrofit products available.

My sincere thanks to all, for the many years of support and trust in Roof Hugger and its’ products.

Learn more about Roof Hugger.

Left to Right -  Bill Wingrove, DJ Highnote, David Hall, Dale Nelson, Brandon King and Kathy McBride