Insufficient lintel on window

[jungle_jim01]

here's one forthe builder's amongst you. I have a small cottage style window approx 40cm width. The lintel stone above doesn't appear to be sat on anything other than being mortared to the surrounding stones and window frame. Obviously the ideal would be to pull the whole lot out and reinforce somehow but it's a job to far at the moment. It's obviously been in there quite a long time as the window appears to be fairly old. And there's no obvious signs of movement. So is it possible that just the mortar is holding it in place? or could there be some kind of internal support that i can't see. Has anyone had any similar issues?

This has come about as i'm re-pointing (still!) and unsure whether to remove the cement pointing around this lintel...hmmm...the adventurer in me says there's only one way to find out...don't really fancy that approach this time though!

 

[Penners]

It's surprising how often you see window frames that appear to have no lintel whatsoever above them. There's just the window frame itself supporting the masonry above.

Mind you, if the masonry has been laid with a passably good bond, the load on the window may not be as great as you might imagine. If the window were removed, well bonded masonry should only collapse in the form of a triangle the width of the reveal - the whole wall wouldn't (er....shouldn't!) collapse.

How about posting a photo?

 

[d49xc]

I've seen worse....

Former doorway opened up to become a full passageway - probably 5ft or so wide as I recall.
Wall above non supporting so only went up to the ceiling/upper floor joists.
Yes there was a lintel fitted during the work to support the brickwork above....but....
The lintel was actually not doing anything as there was a clear gap above the lintel to the bricks above for the whole width of the opening.
This situation had existed quite happily for some 50 years+knowing the date when the mod' was done)
I packed up the lintel at its supported ends so now it was flush against the bottom of the bricks above (lime mortar'd place)

 

[Flyfisher]

I've posted this photo before but this seems a good opportunity to give it another airing. I'm not certain of the actual problem as I've not removed any plaster/render to investigate but my assumption is that years of water ingress from a leaking roof into the top of the rubble wall has resulted in loads of water settling on a wooden lintel and causing it to fail, thus transferring the wall loading to the window frame and causing it to distort. But the degredation is quite slow and graceful, possibly because it's a substantial old oak frame - which makes me wonder how much pressure is actually needed to do such a thing. :shock:

 

[MdB]

Main roof A frame resting on top of the middle of a plastic window. There are only 6 A frames holding the roof up so there must have been a fair load on the frame. There was no signs of distortion though on the frame and it had been like this for at least 13 years.

In this case I did remove the window and fitted a proper lintel as it wasn't something I was happy with at all.

A picture would help people comment on your arrangement.

 

[jungle_jim01]

wow! I feel slightly better seeing those! here's a picture of the lintel. I guess that being quite small, the cement could be holding it together. I've repointed the top join with lime mortar so will probably leave it for a while before doing the bottom.

 

[jungle_jim01]

ooops...this forum doesn't like portrait shots then!

 

[MdB]

In my very inexpert view, I wouldn't be worrying about the lintel at all. The absolute worst that could happen is the lintel stone and the small one above it could collapse. The rest of the wall would be fine. If this was to happen (which would be very unlikely I would have thought) then all you would have to do is get them put back together with a piece of steel to stop it happening again. It would be a pain in the rear but not the end of the world.

I would do absolutely nothing apart from monitor. If you were to remove the window frame for some reason then I would probably want to support the lintel just in case but that would be it.

(Usual caveat about following structural recommendations from random strangers on the internet very much applies)

 

[Flyfisher]

The 'lintel' block looks as if it's overlapping the window frame on the right-hand side, albeit not by much but enough to keep any weight off the window frame, and I can't see it 'slipping off' anytime soon.

The left-hand side looks as if the wooden 'lintel' (or is that a part of the frame?) is also overlapping the block underneath, although not as much as the the RHS, so I reckon there's a lot more support for the 'lintel block' than might be initially thought.

I can't see how that 'lintel block' could move down, even if the window frame was removed (not the top piece of wood), unless the sidewalls somehow moved apart. Plus the fact that the window itself is quite small but looks substantially made, so that would be providing quite a bit of support anyway.

All in all, I agree with MdB (including his caveat :wink: ) and I wouldn't be losing any sleep over that window arrangement.

 

[biffvernon]

I generally make my windows on the assumption that there is no extra lintel

Good stuff, oak.