Later addition window opening

[fernicarry]

This window opening was knocked through the back of a cupboard recess by a previous owner. I know who it was, his wife visited us once and mentioned the "wonky window" that her husband put in. According to a local tradesperson he (the PO) had a reputation for random modifications with the help of his squad of sailors from the nearby base. This would have been 70's or early 80's.

The casement window is well and truly life expired so I'm stripping it all away and will replace with a 2 over 2 sash to match the others. Possibly sliding, more likely just a fixed light as its quite a small opening.

Obviously no stone cill originally and the PO didn't make any attempt to form one so that's the first task. Can I just form it out of lime mortar? It'll only need to protrude about an inch so not a crazy amount of material. I'm guessing I would need to attach shuttering to hold it in place whilst it goes off? The other window openings have a raised square ribbon all the way round so I'll try to recreate that in the same way, probably after the new window box is in so I can do the ingoes at the same time.

The recess has a wooden lintel on the inner face which is a bit soggy at the outside edge but otherwise seems sound. Commander V. has added a concrete lintel on the outside of the opening, not exposed enough of it yet to establish its width and how much its resting on the adjacent masonry. The two lintels don't quite meet up so there is about 3 or 4 inches of the wall depth unsupported.

Picture is after a morning of chipping away the cement around the opening and digging out some fine cracks, some of which became significantly less fine...



No signs of movement internally, cornice and ceiling are actually quite good comparatively. Externally however, the two cracks running up from the top corners of the window are a bit concerning. There is also a very deep crack below the window. How worried should I be?

I think the window opening was made after the wall was smothered in cement pointing because I can tell the two layers apart and the window layer is above the pointing layer. I'm willing to believe that the cracks are just the masonry settling onto the new lintel.

I'm going to try to wiggle a bit of 4x2 on its edge in between the two lintels to add some support. Other than that I'm inclined to just repoint and monitor it. Realistically this whole gable needs the cement chipped off and repointed in lime but not up for that at the moment.

Any other suggestions?

 

[aockenden]

“I'm willing to believe that the cracks are just the masonry settling onto the new lintel.” - that was what I was going to say

 

[fernicarry]

Thanks aockenden. I've removed the window frame now which gets me a better look at the lintel. I can get my hand in above it for quite some distance so appears the masonry is barely resting on it and its only been lightly pointed from the front. That would support the theory that the triangle above the lintel has just dropped a wee bit and the wall is no worse off than it would otherwise be. I'll pack more mortar and stones in from the inside and that should hopefully stabilise it all.

I've also chipped off a lot of the cement around the opening. It was actually really well adhered on the sides and top and bloomin' hard work to shift it. The only weak point appears to have been along the bottom of the opening which was all very cracked and loose. This was probably letting water run into the masonry below the window and hopefully explains the big crack there. The first couple of rows of stone below the window are also very loose and will need to be re-bedded.

Any thoughts on forming up a proper "cill"? I'm now thinking either a row of bricks end-on so that they stick out slightly or a even a pre-cast concrete lintel cut to fit, then parge over with some lime mortar.

 

[aockenden]

So you don’t want a proper stone cill? Are you trying to match the other cills on the house? Got Any pics of those?

 

[CliffordPope]

I've done something rather similar to you with a small window. I cast a cement cill in situ, making a wooden former out of plywood, held in position until set with some props and lots of rocks leaning on them. I sloped the top face, and included a drip groove by nailing a suitably shaped piece of dowel in the bottom of the wooden box, near the front edge.
Over the years it has weathered nicely with lichen and moss growing on it. Another cill I painted to match the other slate originals, and that weathers too.
The cement simply fills any void behind, and locks into whatever stonework is there.

 

[fernicarry]

So you don’t want a proper stone cill?

I'd be very happy to have a reclaimed sandstone cill. To fit it wouldn't I have to rebate the stone work either side so that its a little wider than the opening? Not too keen on doing any more surgery on the opening tbh just in case something moves. Or I could try to cut the cill to the width of the opening leaving a couple of little ears sticking out either side. I'm not too optimistic about that being successful though.

Admittedly I'd have to do the same with a pre-cast concrete cill/lintel but if the ears broke off of that I can just form up the missing bit with mortar. Advantage being I get a level surface to put the window on. Off the shelf lintels don't seem to be terribly deep though. Or cast the whole thing in mortar as @CliffordPope has done. Would lime mortar work over that sort of area, or is it liable to crack as it dries?

 

[aockenden]

I'd be very happy to have a reclaimed sandstone cill. To fit it wouldn't I have to rebate the stone work either side so that its a little wider than the opening? Not too keen on doing any more surgery on the opening tbh just in case something moves. Or I could try to cut the cill to the width of the opening leaving a couple of little ears sticking out either side. I'm not too optimistic about that being successful though.

Admittedly I'd have to do the same with a pre-cast concrete cill/lintel but if the ears broke off of that I can just form up the missing bit with mortar. Advantage being I get a level surface to put the window on. Off the shelf lintels don't seem to be terribly deep though. Or cast the whole thing in mortar as @CliffordPope has done. Would lime mortar work over that sort of area, or is it liable to crack as it dries?

Yes the best bet would probably be to cut away some stone on the corners of the reveal to form a “slot” into which the new stone sill would slide. I recently did this with two reclaimed slate sills that I got from a local reclamation yard and installed into an outbuilding. Obviously that’s kind of fussy but I agree it’s better than leaving thin, breakage-prone ears hanging unsupported to either side. The cast-in-place option is pretty fussy too tbh, as building the form will be fiddly.

 

[fernicarry]

Thanks for the comments. I've decided to go with the form in place approach. Despite borrowing a big boy's 9" angle grinder and buying a couple of concrete lintels yesterday, when I stood in front of it this morning and contemplated the next move it was all a bit too far out of my comfort zone.

So I bedded the loose stones back in place, screwed a 2x2 onto the wall where I want the bottom of the cill to be and ladled lime mortar onto it. The mortar holds its shape pretty well and nothing leaked out the bottom so that was all the form-work it needed.

After a bit of judicious tapping and cajoling with a dust brush I think it turned out not completely horrible. Its not exactly flat or level but nothing around here is.

Whether its still in place tomorrow, or its all on the floor, we shall see...

 

[fernicarry]

You've met the window that used to be a cupboard, now let me introduce the door that used to be a window...



In a similar, very rotten, state to the window. This actually seems to be the second door that's been fitted here as you can see by the gaps around the frame.

A particularly nice touch was continuing the concrete slab about 6" into the room and entombing the door jambs.





Today I finished breaking up the slab. Tragically the old sandstone window sill had been smashed up and used as a sub-base for the slab.



I have a pair of reclaimed french windows on the way to me which hopefully I can make fit. I also have an extremely heavy oak sill from another reclaimed door set so I will build the wall back up a few inches then set than on top. I also plan to incorporate an air vent under the sill. Any suggestions for a not very tall grill I could use?

 

[fernicarry]

Someone must have had shares in Ronseal!

 

[fernicarry]

For the last few weeks I've been repairing and altering a pair of french doors for the old window opening. I'm now struggling to find a suitable means to operate them because of how thin the stiles are. There is really only 1" of solid stile to attach to.

I thought an espagnolette might be suitable but the handle case for those seems to be closer to 40mm wide so it would need to overlap the moulding. I suppose I could glue a sliver of wood behind it to support it but I think it would end up looking clumsy.

For insurance purposes I will probably fit rack locks top and bottom on each sash.

Any other suggestions?