It should be noted that when multi-layer wraps are used, each individual
layer shall be firmly bedded and adhered to the preceding layer or the
substrate before the epoxy on the preceding layer is fully cured and is still
tacky. Curing time and temperature of wraps should be maintained,
according to the instructions supplied with the epoxy. The cured composite
should have a uniform thickness and density, and low porosity. Application
of FRP to concrete with temperature outside application temperature range
should be avoided. In addition application to concrete less than 30 days old
[due to concrete shrinkage] or with curing or sealing membranes should be avoided .