Planning all penetrations, and methods

[Norbert]

I am keen to get all wall penetrations properly planned and executed. Reading through this forum and elsewhere there appear to be 2 approaches to managing wall penetrations.

1. Make a hole. Put the cable  through the membranes and insulation, carefully sealing around them internally and externally with EDPM grommets, tape, sealant etc.
2. Install a plastic pipe big enough for the cabling, seal with a grommet. Later when doing the electrics put the cable through the pipe then make airtight with foam and or sealant. 

 

I like 2 better, it allows the insulation and VCL to be installed well ahead of the services, it is then a simple matter to seal everything up. Any advice or opinions on the above?

Edited April 28 by Norbert

[Iceverge]

I would go with a version of #2. 

 

I assume you are doing something like timber frame with blown insulation? 

 

 

Those grommets are hella dear. Use an offcut square of plywood instead of the membrane where ever you need a penetration. Drill a hole in the interior and exterior and push through the conduit. Have a slight slope towards the outside for drainage. Seal the ends with some airtight sealant. 

 

More robust and cheaper than grommets. 

[Norbert]

Timber frame with 140 studs with PIR between, plus another 50 of PIR on top.

 

Yes the grommets are costly, but I am thinking I will need very few of them. However I can see that a plywood offcut would work too.

Edited April 28 by Norbert