Add new window in a concrete block wall

[PC]

We have a downstairs bedroom that is a bit of a dark dungeon with one existing window.
I would like to cut in a new narrow awning window through the other concrete block wall.

Has anyone done something similar?
Any recommendations on how to proceed?
Perhaps run around and get the building permit myself then find a builder/concrete cutter?

[jimO]

i would suggest that you contact a builder first, he will give you the good oil on what happens next

[mrsaneperson]

We have a downstairs bedroom that is a bit of a dark dungeon with one existing window.
I would like to cut in a new narrow awning window through the other concrete block wall.

Has anyone done something similar?
Any recommendations on how to proceed?
Perhaps run around and get the building permit myself then find a builder/concrete cutter?

If you go through council they will need an engineering report.One of the big things to get right is to adequately waterproof the window. Because its an existing concrete block wall its not easy to backset the window.One solution around this is to afix an aluminium sill to the exterior wall above the window this will help keep it waterproof & act as an eave .

[PC]

Thanks.
The existing '70s single pane, no drainage channel, aluminium window - also in a concrete block wall - doesn't have any flashing above it.
Seems rather wrong!
Was thinking of replacing it at the same time.

[DaveW]

Thanks.
The existing '70s single pane, no drainage channel, aluminium window - also in a concrete block wall - doesn't have any flashing above it.
Seems rather wrong!
Was thinking of replacing it at the same time.

Listen to JimO

[mrsaneperson]

Thanks.
The existing '70s single pane, no drainage channel, aluminium window - also in a concrete block wall - doesn't have any flashing above it.
Seems rather wrong!
Was thinking of replacing it at the same time.

Is it backset? Usually the ones i have seen that are backset are installed at the time of the wall construction , and they dont usually have an eave due to been backset. They do usually have a bottom concrete sill that helps run the water away from the window.

[PC]

Nope - flush - would have thought some sort of flashing across the top would be a good idea.
Not very exposed to weather and doesn't seem to leak.

[Leftette]

You'll need a new lintel above the new cut-out section, won't you?

[mrsaneperson]

Mine looks similar to that one pictured but with an aluminium flashing glued onto the block immediately above the window.Without the flashing mine leaks .Perhaps there is a better flashing available rather than just something glued to the block that forms an integral part of the window.

[garrett]

You'll need a new lintel above the new cut-out section, won't you?

It depends which way the floor joists run. If parallel to the window, one may act as a lintel. If joists are landing where a lintel should be then most definitely.

A recessed window can use a chased in head flashing in the recess. The jambs should have a PEF backing rod with sealant. A face fixed window head flashing should lap behind the weatherboard above and the jambs should have a sealant bead or inseal strip between jamb flange and block face.

[Airpropty]

I had a similar problem with a basement room where there was hardly any natural light, old single-pane windows just made things feel more boxed in. When I decided to cut in a new opening, I went through council myself for the permit but got an experienced builder to handle the actual wall cutting and install for peace of mind. Swapping out the old window at the same time was worth it, especially if you want the same style; just make sure both get proper flashing since most vintage stuff just skipped it back then. One thing I tried in my new window setup was adding switchable window film instead of regular glass or blinds. It makes the room way brighter and gives privacy on demand, which was a cool upgrade from traditional curtains.