Opinion on window position

foxirl

Hi all,
Question on Corner windows.
Option A:Windows in line with outter edge of outter leaf so no need to turn stone work back in.
Option B: Window in line with insulation beside outter leaf but will need to turn stonework back in to cover edge of outter leaf.
Pic attached if above doesnt make sense.

Would like to hear peoples opinions on this taking into account the best option in terms of cold bridging etc.

Thanks

bemak

A - would look weird to see frame top and bottom but not on the sides. Also, Option B could be a pain in the arse if you need to replace the glazing for whatever reason.

BryanF

B is better thermally with the info shown. Purely in terms of window position.

foxirl

BryanF wrote: »

B is better thermally with the info shown. Purely in terms of window position.

I think I'd prefer option B based on my limited knowledge but waiting to hear back from engineer.
Can you ellaborate on why its better thermally?

It does mean I need to ensure the block layer leaves outer leaf block back enough from window to allow the stone to return back in.

BryanF

foxirl wrote: »

I think I'd prefer option B based on my limited knowledge but waiting to hear back from engineer.
Can you ellaborate on why its better thermally?

It does mean I need to ensure the block layer leaves outer leaf block back enough from window to allow the stone to return back in.

Do you have the 1:5 or 1:10 detail you can share? Are you going for the lower psi values to improve the BER?

eoinzy2000

foxirl wrote: »

I think I'd prefer option B based on my limited knowledge but waiting to hear back from engineer.
Can you ellaborate on why its better thermally?

It does mean I need to ensure the block layer leaves outer leaf block back enough from window to allow the stone to return back in.

It's better thermally because you have a thermally broken frame at insulation line, therefore separating heated/unheated space. When flush with outside at the front, a portion of the outer leaf is potentially bridging to the inside, causing thermal bridging. There may be clever ways to treat this by dry lining the reveals, but the outer leaf will be hitting the inside edge of the window frame, potentially bridging outside/inside materials also. Not a wise move I would think.

foxirl

BryanF wrote: »

Do you have the 1:5 or 1:10 detail you can share? Are you going for the lower psi values to improve the BER?

BryanF - I dont have any details on the corner window unfortunately. From the pint of view of construction drawings I have plans and elevations but they don’t go into the detail you are looking for.
Just trying to figure out the best approach to the placement of the window both from a thermal bridging and aesthetic aspect. So far I think B works better and looks better but there is a bit more work involved for both block layer and stone mason based on my very limited knowledge.

sydthebeat

the location of the corner post will be dictated by the lintel company.
it may not simply be a case of pushing it to the outer leaf as they have to take into account twisting actions etc