What type of adhesive for fibreglass treads on concrete steps ?

[Jim Hawkins]

The treads are about 700mm X 25mm The steps are outside our back door. Adhesive must be fairly thick (not runny) and must not go off too quickly.

[The Natural Philosopher]

car body filler or epoxy mortar

[fred]

In article , Jim Hawkins writes

I'd suggest some sort of waterproof 'sticks like shit' product applied in the traditional squiggle fashion but with a fine bead front, back and sides (as a bed) to keep the water out. My fave at the mo is Plumbers' Gold which is an adhesive and sealant that will bond to damp masonry if reqd. The slight flexibility should help too:

mask off the surrounds as it will stick to anything and will likely squeeze out when you bed the step.