Opening a window up into a doorway

[Student]

Hi

 

I'm hoping to convert a downstairs, rear window into a set of french doors out into my garden, I'll leave the opening the same width or maybe even go narrower. It's a Victorian terrace and the existing lintel is the original timber one. The image I've attached is an old photo showing the lintels in that room, though those wall are now plastered.

 

Do you see any reasons structurally why the brickwork at the bottom of the window can just be cut and knocked through? I've also attached a view of the window from the outside (it's the downstairs window on the main house, not any of the extensions). Appreciate any advice.

[Mr Punter]

Normally the answer would be no problem, go ahead, but the inside picture does not show a lintel above the window and it looks like the top has been infilled with brickwork built off the top of the window.

 

I may be that there is a proper lintel above this, but it is hard to tell. 

[Patrick]

Just now, Mr Punter said:

Normally the answer would be no problem, go ahead, but the inside picture does not show a lintel above the window and it looks like the top has been infilled with brickwork built off the top of the window.

 

I may be that there is a proper lintel above this, but it is hard to tell. 

Agreed. I ve done the exact same at my semidetached, just took the window out and cut down to the floor with a concrete cutter, but there was a lintel above the window, so this might be a problem. If there's is none at yours, you want to stabilise the ceiling first, then knock the window out and put a lintel in before doing the door

[Student]

Thanks guys.

 

There is a lintel there, it's almost at ceiling level so hard to see. You can probably see it if you look closely, the left end of it is level with the right side of the doorway lintel and the right side of the window lintel is about 100mm away from the corner of the room. It's by no means the most substantial looking lintel but it's the same size as others in the house.

 

I've since replaced the doorway lintel with a concrete one as the plasterer thought it looked damaged. Had I been able to replace the window lintel without damaging the ceiling, I would have. The simplest, non-invasive solution would be to add a concrete lintel below the timber one but I'm hoping I can get away with just cutting the bottom of the window away!

[jfb]

if you don't need the height of those extra bricks just below the existing lintel  for the door you have room for a 140mm deep lintel under the wooden existing lintel.

You are going to have to door some repair/patching when putting in the door anyway so it isn't much more effort to get a lintel in. Personally I would do it.

[Student]

That's fair. To make the decision even easier, I have a spare 140mm concrete lintel in the garden that I didn't end up using for a different window... just the faff of renting props and strongboys...

[Patrick]

3 hours ago, Student said:

That's fair. To make the decision even easier, I have a spare 140mm concrete lintel in the garden that I didn't end up using for a different window... just the faff of renting props and strongboys...

If you near Bath, I have some props rusting away in the garden you can have as long as you need them.

[Student]

That's very kind of you! I'm actually not that far away (Bristol) but I think it'll be easier to get it from the local hire place, appreciate the offer though.

[Student]

Getting back to this over the next few weeks. I've got a well over-specced lintel ready to put in. Plan on whacking 3 or 4 strongboys in the gap under the existing timber lintel (I've added a few new photos with the lintel in red).

 

Looking at strongboys, they can take 360kg each. Am I correct in thinking that when you're supporting the opening during a lintel replacement, you're not actually supporting the full load? Otherwise I'm going to need like 5 strongboys in that gap to match my lintel strength (17kn/m).

 

Lastly, I've only got a suspended timber floor as a base for the props. and the joists are running parallel to the window wall and the joists aren't particularly beefy. I could really do without having to lift all of the floorboards to get access to the (frankly, quite soft concrete oversite) floor below the timber floor to put a sole board down but is this the best thing to do? the existing joists are only 3x2 and spanning quite large distances. Nothing is easy in this bloody house!

 

Appreciate any tips!

[bassanclan]

As it's a victorian terrace it is going to be a double skin solid wall.

Are you putting a new lintel on the inside and the outside at the same time?

You'll need some scrap slate or steel shims to pack up the lintel.

2 strongboys will be sufficient, that opening only looks about 1m wide.

[Student]

Thanks, I'm going to take out the bricks above the window on the inside and see what the current setup is because on the last lintel I did at this house, the external lintel was resting on the internal one, so I couldn't do the internal one without supporting the external one too and I ended up just replacing both as I had to disturb the outside one. I'd like to just do the internal one for now but I'm not ruling out doing the outside one in the near future, it's just that the internal one is stopping us installing the doors and therefore stopping us from decorating that room.

 

I'd prefer to bed the concrete lintel on mortar (as per the manufacturers instructions) and then dry pack (3:1 mix) above the lintel instead of slate, I preferred this to slate as the load is more evenly distributed. I got good results with pinning with dry packing and then filling the strongboy gaps with mortar after. See any issues with repeating this approach?

 

Also, any comments regarding supporting base for the props?

Edited August 1, 2019 by Student

[Ferdinand]

Just a heads up to think about how you will use the doors.

 

If 1-1.2m it can be a pain walking through with eg a tray, as you have to put it down and open both. OTOH 1m is wide enough to be awkward for a single upvc door. In accordance with Hitch Hiker tradition, the width is probably almost, but not entirely, exactly unlike what you actually want it to be.

 

If you are having it made, rather than a £100-150 nearly new thing off eBay, then it may be worth considering a sidewindow and single normal width door.

Edited August 1, 2019 by Ferdinand

[Student]

I'm inclined to agree with you there but fear I'll probably be overruled with looks over function on this one unfortunately!

[Student]

Did this. Used two strongboys and put a concrete lintel underneath the original that I couldn't remove and dry packed it in place. Used a 9 inch grinder and a sledge hammer to open it up. Took a whole day to get them in and need my mate up toe and heel the glass but not too bad a job. Nerve racking at the time though.