What is the minimum slope required of LWIC?

The minimum slope is 1/8 inch per foot to provide positive slope and to insure that water will drain. Consult local building codes.

What are the advantages of LWIC over rigid insulation board?

The advantages of LWIC include fire resistance, wind uplift, and seismic ratings, positive drainage, dimensional stability, moisture resistance, and re-roofable. LWIC is permanent, non-combustible, strong, economical, approved, and roofing compatible.

How thick is LWIC poured?

Both aggregate and cellular products are placed at a minimum thickness of 2 inches. One aggregate product can be placed at a thickness of 1 inch. LWIC systems (LWIC plus EPS Insulation) may be placed at a thickness greater than 18" depending on the specified slope (1/8 or � inch per foot).

What precautions should be taken for top coat casting if snow is forecast?

If possible use heated mix water and/or High Early Strength cement (Type III) to accelerate the setting time before snow occurs.

What is involved in re-roofing over LWIC?

In many instances, it may be acceptable to cast LWIC directly over an existing membrane and insulation system. If the membrane is removed and there are base sheet nails of holes left on the deck, they shall be handled per specific job conditions. Unlike insulation board systems, just remove the existing membrane and install a new membrane per local requirements for acceptability. The LWIC system is permanent and does not need to be replaced.

Is it possible to cast over an existing LWIC roof (re-cover)?

Per structural engineer approval, cast new LWIC over existing LWIC and then apply the roofing membrane. Follow the procedure outlined in NRDCA Standard 500 for additional information.

How long does LWIC last?

If maintained in a watertight condition, LWIC should last for the life of the building.

How long is the warranty for LWIC?

One year from the date of substantial completion.

What regulatory approvals exist for LWIC?

All products have FM (wind uplift) and UL (fire resistance) listings in addition to national and local code approvals.

Is LWIC a green product?

Yes. LWIC has appropriate credits for these requirements.

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