Foil covered pipe insulation

[richierich]

Has anybody used foil covered foam insulation on cold weather vulnerable water pipes, such as in the loft as opposed to just general foam or rubber pipe insulation. I'm trying to find out, unsuccessfully at the moment if the foil layer replaces the need for thick walled insulation, for example reducing wall thickness from 2cm to 1cm. 

[JohnMo]

In a word - no.  Foil wrapped is good for two things keeping pipes cool - for cooling duty and for keeping rodents from eating your insulation.  In a loft use 25mm thick insulation.  

[richierich]

Doesn't the top layer of foil reflect the cold whilst the inner foam insulates the water pipe?

[joth]

7 minutes ago, richierich said:

Doesn't the top layer of foil reflect the cold whilst the inner foam insulates the water pipe?

No.F oil reflects infrared radiation. That's heat energy, not cold. 

I use my ASHP for cooling as well as heating, so yeah I should probably foil wrap the ones outdoors. 

 

 

46 minutes ago, JohnMo said:

In a word - no.  Foil wrapped is good for two things keeping pipes cool - for cooling duty and for keeping rodents from eating your insulation.  In a loft use 25mm thick insulation.  

3. It's also good for creating an airtight layer if the insulation underneath doesn't, which is good for keeping moist air out which otherwise might condense on cold pipes within.