Bathroom extractor to loft air brick issue

[Craig24]

Hi all,

The house we moved into has a bathroom ceiling inline extractor fan with round flexible ducting, it has an adaptor to make it brick sized then is pushed up against an air brick in the loft. I assume this is OK as all the other air bricks has been covered over with some sort of silicone after cavity wall insulation?

The issue I have is that the air brick is damaged is allowing birds to nest. I need to replace the air brick but can’t get access from outside without scaffolding. I was wondering if I could remove the air brick from the inside and replace it with just an air brick cover (pulled in with rope and attached with silicone?).

Would it be ok to leave a brick sized hole with just a cover and no proper support?

 

[JohnD]

it would be better to pull up a cowl vent with flap, and fill around it. The vent has mouldings that will fit common sizes of duct, though I would tend to fix a piece of rigid duct with plastic cement, as flexy hoses sometimes fall out. I'd use S&C mortar, though some would bodge with expanding foam (foam degrades in sunlight, and holds water). You will need cardboard or other shuttering to prevent slump.

They are widely available to fit the common 100m duct, but other sizes are available.

The brown colour is not bad in brickwork, but you can paint them with non-drip gloss (easier prior to fitting) if you want.

This design is quieter, and more resistant to rain, weather and wind, than the flappy vent.

www

screwfix.com/c/heating-plumbing/air-vents/cat840496?producttype=cowl_vent&cm_sp=managedredirect-_-hvac-_cowlvent

 

[footprints]

Can you not fit a bit of wire mesh to the inside of the broken vent to stop birds entering?

 

[Craig24]

Thanks both. The reason I don’t want to put wire mesh there is I still can’t properly attach the ducting to the air brick, it’s just pushed up against it?

I’m thinking JohnD’s suggestion might be a good long term fix?

Am I ok to remove the air brick and just have the cowl and ducting? A full missing brick is OK for wall support?

 

[footprints]

Should be fine without extra support, it's ♪ Just Another Brick in the wall ♫

 

[Craig24]

Thanks both. I now have another issue to overcome. The ducting from the ceiling grill in the bathroom to the in-line fan in the loft has a tear. My problem is due to a loft conversion I can see the ducting but I can’t get in far enough to replace and reconnect to the grill from in the loft.

Any ideas?

 

[footprints]

Can you replace a section with a length of rigid pipe that can be manoeuvred into place?

 

[Craig24]

That might work if I get a piece of rigid duct with a 90 bend on the end, I might be able to manoeuvre it over onto the vent cover. Just might not be air tight.

 

[footprints]

A couple of pictures might help.

 

[Craig24]

The gap to fit though is 15cm, so although I can get my hands and arms through I can’t then see, plus that section of ducting to the ceiling is around 2 meters.

 

[footprints]

Ugg! That is horribly cramped! Any chance of routing the duct to another position or fitting a new wall mounted fan on the outside bathroom wall?

 

[Craig24]

Unfortunately that’s above the shower so ideally I need to be in there. I’m wondering if I remove the bathroom ceiling grill, could I attach new ducting to the old and some bow pull it through?

Would it then be possible to connect the ducting to the grill and refit the grill?

 

[footprints]

Seems like the only way is to access the outside push something flexible through from outside then pull a new length of pipe through and fit a proper vent on the outside really.
Depends on the height, a normal house is quite doable but if you are in a taller building not all that practical.