Rotten window lintel, what to do?

[steve mac]

I have an old house, about 180yrs old, which is stone built with wood beam lintels above the windows. We are in the process of selling it and making good some of the bits that were left from a very slow renovation. One of the jobs was to box up the wooden lintels above the kitchen window and plaster, This window was left when the rest of the kitchen was plastered as we found that one end of the first beam (3 beams in total for the depth of the window) had been eaten away by woodworm. This was fixed up after clearing it out, the woodwrom damage seemed to be old and the rest of the first beam looked ok.
Yesterday I went to nail up some plaster board over the old plaster to the underside and found nothing solid behind the old plaster. After pulling off the old plaster I saw that the other two beams had also been eaten away and were a real mess.
The surveyer is coming tomorrow for a full structeral and is going to have a field day with this.
What are the options for repairing this?. Is there no other way other than chopping out the wood and replacing with new timbers/modern lintel, has anyone else had similar problems or had to replace old wooden beam lintels?

 

[Static]

If you have lost more than 1/3rd of the cross section you should be looking to replace it. Are there signs of cracking around the window? What is above the lintel (ie brick wall, 1st floor, roof etc)?
Take some photos.

 

[steve mac]

Above the lintel is about 2.5 foot width of stone wall. There are no cracks and all the stone wall appears solid. The beams will def have to come out asthe middle one in particular has a cross section of about 10% let alone 66%.
I was wondering if there are methods of repair other than chopping out what's left and fitting new timbers. Is there a way of filling the void with concrete or would this not be strong enough?

 

[Static]

Infilling the gap would not assist the problem. There doesnt seem to be alot left of the existing lintel to fix any remedial solution to.
One option would be to put a new lintel above the old one and then just box in the old lintel if you have the room.
What size is the window opening? If possible post some pictures

 

[phykell]

I had exactly this problem. I had a wooden lintel with a huge crack right in the centre. It was only a single floor extension with only around 2' of brickwork above it, but you could still see where the window frame was taking the weight (slight bend). I replaced my wooden lintel (slightly less than two courses thick) with two concrete lintels (each one course thick) which cost very little by easing out the wooden lintel and placing one concrete lintel first, then removing the wooden lintel completely and placing the other concrete lintel. It was a bit nerve-wracking but actually quite straight-forward as it turned out. The concrete lintels have steel wire running through them and are available in lengths up to 8' (2.4m) with various widths and heights. Interesting information here:

http://www.stowellconcrete.co.uk/home/products/lintels.htm

I used the 100mm x 65mm section ones with a 6" overhang onto supporting brickwork either side so an 8' lintel will fit over a 7' (maximum) window.

 

[hammerboy86]

Have replaced many timber lintols over the years, a couple of PC lintols will do fine, remember to use acro's, better safe than sorry. If there's a lot of thick, possibly loose stone, needles through the wall will hold up the stonework

 

[clarkyboy]

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