Air gap between Duratech and thimble

[Bootjack]

I am installing through the wall 6" Duratech. There is a gap of about a 1/4" between the pipe and Duratech collar. This seems large. I am concerned that the supplier may have put a larger diameter thimble (maybe for a duraplus) in a duratech 6DT-WT box. The box was open when I purchased it. If this is an acceptable gap, how do you air seal this?

 

[begreen]

Use a good quality silicone adhesive like GE Silicone II to seal the gap.

 

[webby3650]

Get some black silicone and seal around the pipe at the thimble. Then install the thimble cover.

 

[webby3650]

Dura tech only has a single piece inside I guess. Just make a clean bead of black silicone around the gap. I can’t believe they didn’t even caulk outside. Strange

 

[Bootjack]

Thanks all. The gap is apparently normal. The pics just shows the pipe fitted to see how things look. I didn't like the gap. Now I know how to deal with it but still think they could have had tighten the tolerance.