Sealing holes around mpde and copper pipe

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Can I use external frame sealant (acrylic) to fill gaps around an incoming MPDE blue mains cold water pipe and, separately, copper oil pipes and hep2o pipes? Any issues with material compatibility?
 
No issue with it damaging pipes but it's the wrong stuff. Driers and won't move enough.
Pipes through walls should be sleeved and caps put around to make them look tidy.
Pipes expand with heat causing them to rub against masonry.
Most don't sleeve and use a natural cure silicone or polymer mastic around the seal in. That's your best bet.
Always use correct mastics for any job.

 
No issue with it damaging pipes but it's the wrong stuff. Driers and won't move enough.
Pipes through walls should be sleeved and caps put around to make them look tidy.
Pipes expand with heat causing them to rub against masonry.
Most don't sleeve and use a natural cure silicone or polymer mastic around the seal in. That's your best bet.
Always use correct mastics for any job.

So a low modulus acrylic sealant? Don't want anything acidic as this eats through pex/PVC. My mode pipe is 20mm diameter. What pipe cap/sleeving should I use? Needed to stop insects getting through
 
Natural cure silicone or polymer.
CT1 or 0b1 or stixall which is cheaper is a polymer.
Sometimes clear is better than white..
 
So a low modulus acrylic sealant? Don't want anything acidic as this eats through pex/PVC.

There is such a thing a neutral-curing silicone. I have used the no-nonsense one, it’s fine.

(Note “neutral”, meaning not acidic, not “natural”!)
 

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