Replacing a lintel - delicate wall - need advice

[Cloudscape]

On the end of a long lean-to section, which badly needs repointing, I have a door (200cm high) with glazing above. The thin lintel looks pretty far gone, and I think the wall is held up by the doorframe. But this frame has been patched and added to, and is rotten in places. (The inner skin of stone has a slghtly better lintel and the lime plaster is still attached.)

View attachment 2
View attachment 1

The external lintel doesn't look as though it extends into the left-hand wall, and barely laps onto the brick on the right.



As soon as the weather improves, I think I need a new lintel, frame and door. Please could someone with experience tell me how much of the wall is likely to collapse. I'd really like to avoid changing more than I have to. I like the house the way it is.

Should the wall be pointed and consolidated before removing of the wood? Is this a case where needles might work (I've never used them). Any suggestions for order of works would be gratefully received.

 

[Me!]

What you need is a StrongBoy ........ (Oh where is Grimmers when you need him!)

http://www.strongboy.co.uk/index.php/cPath/23?osCsid=9ppl4g4a2sts8q23650apulim5

You fit them to the top of Acrow props, and drill out enough of a mortar bed that the thin metal plate can be inserted into the gap and then tighten the Acrow. For an opening the width of a doorway one is usually sufficient, but if you are worried about the state of your mortar then use two. There is no reason why any of the wall above needs to fall down if you do it this way.

The last time I hired them, I think I paid about £5 for a week.

Good luck, but it really isn't difficult, and it certainly doesn't need to be dangerous.

 

[Nemesis]

That wall looks to me like some careful repair rather than total repointing is needed - it's wonderful!

 

[Lime]

It looks as if there is a 45 degree crack running upwards from the righthand top of the lintel towards the wall.
The down pipe blocks the view of the junction of the walls.
I'd use plenty of support as walls with little weight above them are often more fragile than those taking larger loads.

 

[Cloudscape]

I see the crack you're talking about. It's partly delineated along the edges of stones that fall along the line. The wall facing you, the end of the lean-to section, might be tied in on the left, to the back wall of the stable. If it is, an internal crack says the tying in doesn't amount to much. The wall you see on the left is the coach house section. That's definitely not tied in. It's a three-sided addition. These are my favourite two walls, because they have had the least interference. What you see is what you get, with a few surface traces of limewash.

The end of the coach house has been repointed in cement, although not totally, and some of the repointing is superficial. If you carry on round the house, you get a mish-mash of limewash and paint layers and more and more cement.

I would certainly have a go with the strongboys, but this seems to me like a one-chance operation. I really don't want to spoil what hasn't yet been spoiled.

Thanks, Nemesis. I'll try and take some better photos when it's not so cold.

 

[middi]

Have you checked properly if that external (oak ?) lintel is actually rotten ?, Try inserting a two inch screw into it, if it "bites" well then leave it alone and just raplace the door frame with a 3 inch thick top rail. I know that I am quite far away but it looks ok from here.
It should last a long time ( longer that you and me anyway). Just rake out an repoint.

 

[Gervase]

I'd agree that a strongboy is the way to go if you want to replace the lintel but - as Middi says, if it's oak, the chances are that the breakdown is just on the surface and it still has the strength to do the job.
Remember, if you're using an Acrow, to be careful to crank it up just enough to support the work - don't be tempted to wind it really tightly, as the upwards force can break the bonds in the masonry and weaken it still further.
In my house I've got an upstairs floor which bows like the deck of a boat where a previous owner jacked the joists up to scarf in new ends (bedded into the wall in concrete - Grr!) and got carried away with the winding. I say 'scarf' but the ends where simple butt-joints, with a quarter-inch gap, with side cheeks made of shuttering ply held on by four one-inch screw! It was one of many surprises when the plasterboard was removed...

 

[Penners]

The way that brickwork will collapse in such cases is fairly easy to predict, but random stonework is much more difficult. However, I venture to suggest that - if the worst happened - the stonework would collapse roughly along the diagonal line that Lime has pointed out.

However, let's hope that Middi is right, and your lintel is stronger than it looks.

 

[Lime]

Referring to the crack, it looks as if it could be an old 45 degree roof line from the dim and distant past as the line appears to continue down to the right of the door.
Not being able to examine it in detail or see the whole wall I am not certain though.

 

[Cloudscape]

Here are some better pics. The external lintel is stronger than it looks - you're right. But I now realize that it doesn't extend into the wall on the left, and is only resting on the right-hand side by its fingertips. It looks as though the door frame is holding the wall up, and the right side is quite far gone (hence the patch to keep birds and the draught out).

 

[Lime]

Yes, you can see the same line inside too.
It looks to me that the roof at one time was steeper, lower and ran along the line of the crack right next to the door frame to form a lean-to.
The colour and state of the wall is slightly different/better near the door and that area of wall appears to extend to the right another door's width from the door frame.
That would account for why the door does not have a lintel.
...It wasn't an important room and there was no space to fit a lintel nor much load to take.
The load is still not very great upon the door top IMO so don't worry too much.
With the wall above the door properly supported a new lintel can be fitted relatively safely.

 

[chuckey]

The difficult part , as I see it is the left hand ( from the outside) side. the lintel should really be tucked in behind that other wall, to give it a decent seating. the problem with strong boys is that the acrows should really be at least the width of the lintel away from the wall. This is so the lintel can be lifted up between the acrows and the wall, level with slot, then pushed straight in. In this case to get the end of the lintel behind the "other" wall, the RH side must be swiveled out slightly, before being pushed in. All this fannying about, is OK with 4 1/2" brick skins and 4" lintels but exactly how wide will your lintel be? 12"?
The cheap and nasty way would be to put in 2 or 3, narrow concrete lintels- overcomes strong boy arm length problems and just have a front one of slate as a decoration.
I would go for a 4" thick X 12 " deep slate lintel, myself. Depending if your internal lintel any good (bit of a bugger with those pipes?), I would drill 3 16mm holes just above the new lintels position, hopefully to just over the internal lintels top. bang in 3 bits of steel reinforcing rod, protruding about 12" and use these ends and the really thich polypropolene rope tie the rods up to some sort of structure, a couple of 4" X 2" leaning againt the wall, with another bit of 4" X 2" across the top. Use a spanish windlass to get the rods to bend a bit and away you go (carefully).
Frank

 

[Cloudscape]

Yes... the lovely pipework. I think [Bad Word] is a bit of an understatement. :roll: I've spared you from seeing the rest of that copper sculpture - you should see what happens when the pipes reach the end of the right-hand wall! :shock: One day it will be sorted (I keep telling myself).

I'm grateful for all the input and advice on this. I'm mulling it over.