Close/bridge top of cavity walls? - New build

[Gadgetman Andy]

Hi all,

We are having an extension/conservatory built. The builder has now left site after completing the brickwork construction and gone on holiday. In the next two weeks the conservatory wll be built. The exterior walls will be rendered, when the builder returns.

In the mean time he has left open the tops of the wall cavities, and the insulation is visible below. Not wanting to introduce water into the cavities. Should I close/bridge the cavity perhaps with self adhesive flashband, which could be removed if need be? Or should the cavity be left open or closed?

Many thanks.

[stoneyboy]

Gadgetman Andy,
Drape strips of sacking or something similar along the top of the wall and wait for the builder to return.
end

[Gadgetman Andy]

[quote="stoneyboy"]Gadgetman Andy,
Drape strips of sacking or something similar along the top of the wall and wait for the builder to return.
end[/quote]

Thanks for the reply. Unfortunately before I checked for a reply I have sqirted in expanding foam, that has now cured and been cut off level with the top of the cavity. Was this a bad idea? I could easily pull it back out again if need be.

[stoneyboy]

Gadgetman Andy,
Depends how far down the cavity the foam has expanded, it will have formed a nose down into the cavity which could cause water ingress from the external brickwork if it is an exposed location.
end

[Gadgetman Andy]

[quote="stoneyboy"]Gadgetman Andy,
Depends how far down the cavity the foam has expanded, it will have formed a nose down into the cavity which could cause water ingress from the external brickwork if it is an exposed location.
end[/quote]

Many thanks for the info.

[TheDoctor4]

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