Gap above lintel - caulk, leave, mortar?

[TheFew]

Hi there,

I have some old aluminium patio doors that are around 4 to 5 m long. As you can see from the below pictures there has been some moisture ingress into the inside of the house and the lintel is showing a little surface rust through the plaster.

I had assumed this was because the caulking on the outside had failed, so I pulled it all away.

As you can see, there is a gap between the lintel and the wall above for the length of the lintel, this gap ranges from 2mm to 5mm.

From having had a quick look on the Internet the suggestions seem to be...

1) this gap should be caulked to prevent water ingress.
2) this gap should not the caulked and should be left as a weep hole (but driving rain would come in).
3) this gap should be mortared to ensure that the bricks above are supported.

So in summary, I now have no idea what the best course of action is...

Can anyone advise?

Thanks


Window from outside.


Gap between lintel and Wall.


Rust marks on inside plaster.

 

[Usel]

I'd fill it with this and then paint it within 2hrs of applying. If you paint it after 24hrs the paint may not stick.

https://www.amazon.co.uk/Gorilla-Gl...ocphy=1007261&hvtargid=pla-496550769792&psc=1

 

[pp111]

I can’t exactly tell what I am looking at in those photos, but, based on what I know about aluminium windows, the windows are not made to an exact size, rather there is a wooden surround that can be trimmed to exactly fit the gap. This is what we are looking at. The gap is not above the lintel, rather it is between the wooden surround and the bottom of the lintel. There shouldn’t be a gap at all, because water will run down the wall and naturally tend to run inwards towards the gap, either dripping on the wood, or worse running in to the gap and rotting the wood and or making the lintel above rust. So the answer is to seal that gap. It should have been sealed with the installation of the door. I would get a wire brush and clean off that wood. Splosh some preservative on there and let it all dry off. Completely seal it with a door frame sealant ( no gap required ) and then paint seal the wood with a outdoor varnish/stain. Bear in mind there is some rot to the wood surround so it’s not going to last forever, but it should last a fair old time as long as you treat it now.

 

[TheFew]

I can’t exactly tell what I am looking at in those photos, but, based on what I know about aluminium windows, the windows are not made to an exact size, rather there is a wooden surround that can be trimmed to exactly fit the gap. This is what we are looking at. The gap is not above the lintel, rather it is between the wooden surround and the bottom of the lintel.

Thanks for the thoughts. I assumed that the metal strip above the wooden frame and below the bricks was the lintel as on the outside you can see how it extends into the course of bricks beyond the length of the window and the frame. I'll try to take some better pictures to show what is going on.

Assuming the gap is between the lintel and the wall.. is caulking still the way to go?

 

[Buffman]

I'd hazard a guess that you can either do 1 (with external caulk) or 3 if you're comfortable making a good mix (will have slightly more sand).

Could possibly add something to the mortarix to colour it white even, i know there's colouring additives.

 

[pp111]

Thanks for the thoughts. I assumed that the metal strip above the wooden frame and below the bricks was the lintel as on the outside you can see how it extends into the course of bricks beyond the length of the window and the frame. I'll try to take some better pictures to show what is going on.

Assuming the gap is between the lintel and the wall.. is caulking still the way to go?

Is that metal? I was about to say that if that is the lintel then there is no way it would have been built with a gap. It is possible that the lintel has dropped a smidge and left the bricks handing there all by themselves but I would expect not only cracking on the outside walls but signs on the inside too. Looking at the picture though there are some signs of cracking so maybe it is the lintel. If a gap has opened up between the brick and the lintel then the brick is in danger of cracking even more. The gap needs to be filled with something solid and load bearing to support the bricks. I wouldn't worry about drainage since the outer wall is painted ( means the ingress of water in to the cavity is minimal ). The normal way to fix something like this is to take slivers of slate or something else nice and hard and tap them in to fill the gap , one or two slivers for each brick, to make sure every brick is supported. Then you seal over the top with a frame sealant. Alternatively you could use something like a chemical mortar to inject in to the gap, just make sure you mask off everything with tape first, you don't want that stuff spread all over the place. The chemical mortar is an epoxy cement that is very hard and waterproof at the same time. Easier than messing with slate. It is not as good as slate but arguably easier.

 

[TheFew]

Thanks for the thoughts.

Yes the lintel does seem to be metal, the below picture shows one edge. The gap gets bigger towards the centre of the window.



From the outside you can see some cracks in the brickwork, mostly in the three courses above the window. The mortar has started to come away.





Guess I would need to put some slate into the bigger gaps and then chemical mortar into the rest of the gaps where slate would be too big.

Is there a recommended chemical mortar at screwfix?

Water ingress is a topic of concern for me, as the previous owners had cavity wall insulation installed, so trapped water in the cavity is always a concern.

Thanks

 

[TheFew]

The other question i had... would this metal lintel be the full depth of the wall i.e. span the cavity and support both the internal and external walls. Or is it likely to be just supporting the external wall and the internal wall will have its own?

 

[Kill_Phil]

With anything like this I'd get a professional in, especially with cracks to the brickwork.

Looks like the support lintel has sagged/dropped.

 

[gc123]

had a similar problem with our large bay window when the double glazing firm put the new one in 30 plus years ago they did not fit a lintel just filled the gap between the plastic frame and the bricks above...( took a few years but ended up having to have the whole front wall redone and windows refitted (thankfully bay was ok but bedroom window above had bowed so much it was in danger of breaking the glass).
we only noticed the problem when the upstairs window was struggling to close, then had to get a builder in...new lintel down stairs and a lintel upstairs, however 5 years on and we are battling water ingress above top window ...getting builders to quote over last few years is like pulling hens teeth.


must add when we bought the house it had the old steel window frames installed hence why we went for double glazing....company was named after a mountain

 

[TheFew]

had a similar problem with our large bay window when the double glazing firm put the new one in 30 plus years ago they did not fit a lintel just filled the gap between the plastic frame and the bricks above...( took a few years but ended up having to have the whole front wall redone and windows refitted (thankfully bay was ok but bedroom window above had bowed so much it was in danger of breaking the glass).
we only noticed the problem when the upstairs window was struggling to close, then had to get a builder in...new lintel down stairs and a lintel upstairs, however 5 years on and we are battling water ingress above top window ...getting builders to quote over last few years is like pulling hens teeth.


must add when we bought the house it had the old steel window frames installed hence why we went for double glazing....company was named after a mountain

Wow sounds like bit of a nightmare. Oddly (or perhaps not) the French doors i have a made by a company named after a mountain.

 

[TheFew]

Having had more of a look. It is 100% the metal lintel that is detached from the bricks above. In some places upto 5mm. The lintel has not drooped as such, but has developed a slight wavey nature so that the gap is not biggest in the middle, but opens and closes and opens again as you move from left to right.

I have put some slate in where I can, but for the larger gaps, slate is too thin and I do not want to wedge it in and add more pressure on the lintel.

I guess next I will have to try to pack it out with mortar, but getting mortar in could be fiddly.

In the fullness of time we do hope to get the windows replaced with new ones and I guess that would be the time for a fuller repair.

Am I correct in understanding that the internal walls in a cavity wall build take the majority of the structural load?