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Floricete is approved applicator for Celcore and Mearlcrete. We install lightweight decks for new construction and reroof projects. Overseen by Wally Behrendt, LWIC Division Manager with over 20 years of managing projects in the industry.
Lightweight Insulating Concrete (LWIC) is a cementitious product that achieves compressive strengths of 200 to 500psi, making them a superior system in terms of nailability, stability, wind uplift and fire resistance.
The flowability of LWIC allows installers to achieve positive slope-to-drain easily and eliminates the possibility of drainage issues and/or ponding water in complicated roof drain plans.
LWIC provides constant R-Value that will not deteriorate over time. This sytem does not require “through fasteners’ to secure it to the structural deck which would allow for the thermal briding of exterior temperature to the interior of the building.
LWIC decks are compatible with single-ply, modified bitumen, built-up roofing and many others and there are a variety of single source warranties that can be provided with these sytems, contact FloriCrete for more information.
LWIC is finished in one monolithic pour, therefore not allowing the stresses of movement on a membrane that the intricate seams and butted joints of a rigid board system allows.
Typical Lightweight Insulating Concrete roof systems can be “reused” when it comes time for a new roof. Often the old roof is simply removed, any minor damage is patched and the new roof can be installed with little interruption to the activities in the building below.
| Characteristic | LWIC | Polyiso | Notes |
|---|---|---|---|
Strength | Lightweight Insulation Concrete Systems (LWIC) achieve strengths between 200 - 450 psi, Polyisocyanurate Insulation (PIR) has typical compressive strength ranges in the range of 20-25 psi. | ||
Slope | The flowability of LWIC makes complicated slopes easy as complex designs can be achieved in the field, while PIR systems require multiple layers of insulation, complicated sloped pieces and special cuts are required to achieve difficult drain patterns. | ||
Combustibility | Because it is cementitious in nature, LWIC is considered a non-combustible material, PIR is composed of complex hydrocarbon chains, and is classified as ‘combustible’. | ||
Attachment | LWIC does not require mechanical fasteners to bond to the substrate, and membrane fasteners do not penetrate bellow 2” of the surface material. PIR requires an intricate pattern of mechanical fasteners to bond it to the roof substrate | ||
Thermal Bridging | Lightweight Insulation Concrete Systems (LWIC) achieve strengthss between 200 - 450
psi, Polyisocyanurate Insulation (PIR) has typical compressive strength ranges in the
range of 20-25 psi. | ||
Strength | LWIC does not require mechanical fasteners to bond to the substrate, and membrane fasteners do not penetrate bellow 2” of the surface material. PIR requires an intricate pattern of mechanical fasteners to bond it to the roof substrate | ||
Thermal Bridging | Due to the need for fasteners that penetrate the entire insulation system, PIR systems allow significant bridging of temperature fluctuations between the exterior and interior of the roof system. LWIC does not allow such thermal bridging. | ||
Long Term Stability | LWIC remains stable even after the overlaying roof system deteriorates over time. Reroofing is a much simpler process with less waste as there’s no need for an expensive new roof assembly. | ||
Constant R-Value | PIR are manufactured using HCFC blowing agents that dissipate over time reducing the originally designed R-Value. LWIC is not manufactured in this way and therefore maintains a constant R- Value. | ||
Mechanical Stress | PIR is built on a system of butted insulation boards. These boards can change in size over time and/or allow for movement between insulation boards, causing stress to the roof membrane. LWIC toppings are poured as one monolithic slab omitting these joints/seams. | ||
Green Building | While both LWIC and PIR systems have available LEED points to offer towards Green Building credits, the fact that LWIC systems can remain in place and intact during reroofing makes the system preferable. When re-roofing, the removal and disposal of the existing PIR adds to expenses, manpower, slowly degradable landfill content, etc. | ||
Fire Ratings | LWIC is noncombustible and has many UL ratings, and in some instances, can allow the emittance of costly fireproofing of the underside of the metal deck in many UL Rated Assemblies. PIR systems often require separate thermal barriers to meet UL Ratings | ||
Strength | Lightweight Insulation Concrete Systems (LWIC) achieve strengthss between 200 - 450
psi, Polyisocyanurate Insulation (PIR) has typical compressive strength ranges in the
range of 20-25 psi. | ||
Uplift Ratings | LWIC has numerous Factory Muta! Uplift Ratings and perform as an air retarder providing excellent wind uplift performance. PIR systems require increased numbers of mechanical fasteners in order to meet increased uplift requirements | ||
EHPA | Both LWIC and PIR systems have approval for Enhanced Hurricane Protection Areas, LWIC’s approval far outweighs the approved PIR systems. In fact, LWIC systems have proven to be far superior under actual Hurricane Force conditions. |
