Putting in a ground floor window underneath an upstairs wall

[sjchapman]

I want to knock a window into an external cavity wall in my kitchen to let more light in as the only other window in there (looking out the back) is NE facing so the kitchen gets quite dark.

I realised that there is actually a wall above the area that I want the window. The wall upstairs is separating the bathroom and a bedroom, considering that the house was built in 1966 I imagine it's a standard brick thickness wall (it certainly feels solid when I'm tapping it), but as you can see there is no wall underneath, and as far as I'm aware there has never been. Maybe it's supporting on the joists above it that run in the opposite direction? It's all in good condition.

Anyway, this section of wall sits above the area that I want the window to go. The window would probably be about approx 500mm wide by 600mm high tops. Possibly smaller.. Obviously there will be a lintel above the window but does the position of this wall cause extra problems? Would I need to get a surveyor in or would this (site visit etc) be covered by the councils building regs fees/service?

Any ball park idea of cost? Building regs sign off is £230, then there's the lintel, labour and making good inside

Area in kitchen where I want the window to be:

Untitled

• sjchapman
• 7 May 2015
• 1

Area from the front of the house where I want the window to be:

Untitled

• sjchapman
• 7 May 2015
• 1

Thanks in advance

EDIT: Actually I resume the wall is lightweight block rather than brick.

 

[theprinceofdarkness]

I think because you are modifying the front elevation of your house you will also need planning permission (matching window styles?). I would have a word with your planning dept before you invest too much money in this project. Else it looks straight forward.
Frank

 

[sjchapman]

Already checked Frank - no approval needed by planning. Quick scamp and he'll sign it off on the day. Was surprised.

They seem to have relaxed the planning around my neck of the woods (Epping, Essex) but building regs on my extension were pretty thorough...hard wired linked smoke detectors even in rooms that weren't involved in the extension and LED spots throughout...otherwise no sign off...

After a few months I got round to replacing the 50 halogen spots with 5w LED spots, to get sign off and the building inspector said it was all about energy efficient and being green, and that the petrol that he would use coming round to inspect would be counter productive, so he took my word for it and signed it off...

Still, alot safer those LED bulbs and save a few quid when you've got over 50 of 'em

 

[RonnyRaygun]

If you only want to put in a 600mm wide window, then as long as there is no beam spanning onto the wall above the window, then a standard Catnic CG 50/100 lintel will do the job (check your cavity size to determine the exact Catnic you will require.

It's possible that even if the wall is supported on a beam, a CG 50/100 would be OK, but it would need to be determined exactly what load the beam is carrying.

It may be that there is no beam in place under the wall; it's not unheard of for non load-bearing brick partitions to be built straight off the floorboards, although less common in 1960s houses than those built earlier.

 

[sjchapman]

Cheers for the reply.

My builder has said to get a structural engineer to look at it to be on the safe side, sounds like it might start getting expensive - I presume he'd need to expose the area to make a call? (Floorboards up etc) the room above is all nicely decorated and carpeted.

Also, if I went ahead with this would there be much disturbance inside the kitchen while this was getting knocked out? I don't mean dust and mess I mean would it need to be propped internally as I don't really want to move the units/ work surface etc

 

[sjchapman]

Cheers for the reply.

My builder has said to get a structural engineer to look at it to be on the safe side, sounds like it might start getting expensive - I presume he'd need to expose the area to make a call? (Floorboards up etc) the room above is all nicely decorated and carpeted.

Also, if I went ahead with this would there be much disturbance inside the kitchen while this was getting knocked out? I don't mean dust and mess I mean would it need to be propped internally as I don't really want to move the units/ work surface etc

 

[RonnyRaygun]

IF you are worried about exposing what is in the floor, just design for a worst case, the additional lintel cost will be negligible.

The disturbance shouldn't be excessive, over the width you are describing a single prop will do the job.

 

[freddiemercurystwin]

A builder can soon pop a circular hole in the ceiling to establish joist spans etc, it needn't be intrusive and is little effort to infill afterwards, a cheap and cheerful one man band type of SE will be maybe £75 if you provide him with a sketch and the adequate information, he won't even need to visit, so it needn't cost the earth.