Ventilation in outer leaf

[HughF]

This '46 end of terrace has two, approx 10" square multi-holed air vents built into the outer leaf of the cavity wall, about 2/3 of the way up the wall. One vents the bathroom and goes to a sliding plastic vent on the inside (always closed), the other vents into the spare room where my wife has boarded over the inside vent.

 

The cavity is full fill with blown in, chopped fibreglass. The vents are on the north and west sides of the building and we are on a hill, exposed to the prevailing south-westerlies. This house, is cold...

 

Whilst I've got the scaffolding up on the gable end, I'm thinking about foaming and rendering these over in my quest to make this place less leaky.

 

The plan is to add MVHR to the upstairs rooms including the bathroom at some point in the future, so these holes into the outside seem redundant to me now. I'm thinking about filling them up and rendering them over unless anyone thinks this is a terrible idea?

[tonyshouse]

Good idea, a better idea would be to take them out, remove the liner that will be bridging the cavity insulation. Then fill in the inner shin bit of the liner and add cavity insulation repair the outside skin 

[HughF]

7 minutes ago, tonyshouse said:

Good idea, a better idea would be to take them out, remove the liner that will be bridging the cavity insulation. Then fill in the inner shin bit of the liner and add cavity insulation repair the outside skin 

I didn't anticipate there would be a cavity liner.... that's a good point. I should check that.