Timber window into brickwork, do I need a DPM/Barrier?

[Police State]

I want to replace this timber frame window with a better timber frame window. Do I need a DPM membrane between the brickwork and the frame?

The window on an enclosed balcony with a decent overhang of around a metre.

The new window will be made of Accoya and will be treated on the end grains, etc.





Or can I just more or less fit as is?

[wolfracesonic]

Just fit as is.

[OutInTheShed]

Looks to be sheltered by a big overhang above it?
But a proper job often needs a lead tray to avoid issues of the window bridging the cavity?

I've had grief from this sort of thing, to be fair, it was in an exposed location, but the devil is in the detail as they say!

[Simpo Two]

A roller blind on the outside?

[Police State]

Simpo Two said:

A roller blind on the outside?

Yes, Mad. I didn't put it there.

[Police State]

OutInTheShed said:

Looks to be sheltered by a big overhang above it?
But a proper job often needs a lead tray to avoid issues of the window bridging the cavity?

I've had grief from this sort of thing, to be fair, it was in an exposed location, but the devil is in the detail as they say!

Yes, proper big overhang. I think as Wolfie suggests, just fit as is.

[Police State]

wolfracesonic said:

Just fit as is.

I think I will do that. Sometimes, you just need a 2nd opinion. Thanks.

[mikebradford]

The answer is no

[wolfracesonic]

It probably isn’t critical if the window is has some sort of canopy over it but try to get a deeper cill on the new window so the drip groove in it overhangs the brickwork to let water drip clear. The new window could be brought forward a touch by the looks of it, which would help.

[mikebradford]

wolfracesonic said:

It probably isn t critical if the window is has some sort of canopy over it but try to get a deeper cill on the new window so the drip groove in it overhangs the brickwork to let water drip clear. The new window could be brought forward a touch by the looks of it, which would help.

Do not pull the window forward.
You introduce more chance of cold bridging around your reveals.
If the cills a concern ( which it shouldnt be ) ask for the window supplier to add a cill below the frame.

[wolfracesonic]

I said a touch and as long as the vertical dpc isn’t compromised it will be fine and will have little to no bearing on any cold bridging. The existing window is quite far back in the reveal as it is.

[J6542]

Just order the new window with a 50mm wider cill.
Order it glazed if you have someone to help you lift it in, instead of trying to glaze it yourself. Fix it with wedges and foam or fixing clips instead of frame fixing.