What to put over window of bungalow?

[harrypotter]

I put in new double glazing windows and am soon getting the roof done on an older bungalow, older being not new built but decades old (I have no idea how old). The current structure is as shown below:

At the moment there is the original concrete lintel on the interior block wall. Above the new window is essentially nothing; once the soffit board is fixed and level it sits a couple of inches above the window. Do I need to install some kind of damp protection here?

 

[jeds]

You don't say what material the window is but uPVC frames can be fitted with a packer to increase the depth of the frame. Then the soffit would fit to the top. (or a timber packer if the windows are timber?) I would also insulate the void over the top of the cavity with mineral wool.

 

[harrypotter]

You don't say what material the window is but uPVC frames can be fitted with a packer to increase the depth of the frame. Then the soffit would fit to the top. (or a timber packer if the windows are timber?) I would also insulate the void over the top of the cavity with mineral wool.

Thanks, sorry yes it's uPVC. The windows are already installed so I guess it'll be a bit of a hassle to remove them and put packers underneath...

I'm also asking because I've noticed some mould growth by the window on the inside so thought I'd need to put some damp proof membrane somewhere, but would the insulation you mention also help prevent that?

 

[^woody^]

Mould is condensation related, due to a cold bridge. So you need insulation, not a damp proof membrane - that job is being done by your roof and soffit.

Normally you would have timber or a tray lintel and timber just to support the soffit.

 

[harrypotter]

Mould is condensation related, due to a cold bridge. So you need insulation, not a damp proof membrane - that job is being done by your roof and soffit.

Normally you would have timber or a tray lintel and timber just to support the soffit.

Makes sense, thank you!