Dodgy RSJ / Catnic?? help

[MonkeyHunter]

Hi Guys,

Iv'e recently moved, and while checking existing Supports and RSJ's so I can work out the best way to extend the house and I came across this:

http://picasaweb.google.com/scott.gilchrist/WrongRSJ/photo#5091429793422261778
http://picasaweb.google.com/scott.gilchrist/WrongRSJ/photo#5091429797717229090

Looking at this it didn't seem right that the external leave was only half supported, and on further investigation on the Catnic site, this seems to be a Lintel for a solid external wall, which has been used on this cavity wall (brick inner and outer skins)

This opening has been made to extend the kitchen in to a utility room, the opening is now ~2400 mm, the end bearings seem to be 150mm, though I can only check one end, and on that end it is just resting on the pier.

It's obviously been like this for a while and the house is still standing, can anyone give me an idea of how marginal this is? Do i need to get 1-2 Acrows in the middle of the kitchen straight away, which would be a pita, or do you think I can wait until I start on the extension and have to replace it anyway?

Any SE's in the Bristol area want to do some calcs for some beams for me? - & rough cost? Or any recommendations of SE's in the bristol area?

Cheers,
Scott.

 

[noseall]

there is a certain allowance for oversailing or corbelling in brick walls, it is done all the time. your bricks do seem to be stretching the rules a bit though.

if there are no visible signs of movement then i wouldn't be inclined to worry too much just yet, as in a lot of situations the surrounding brickwork above and to the sides offers a lot of lateral support once all the mortar is cured.

i would think that any impact or disturbance to this part of the structure would probably find the weak points in this part of the build and may result in movement or damage.

 

[MonkeyHunter]

Thanks for your input noseall, when I get a SE round I will get him to have a look. Hopefully it wont fall down in the meantime, on the pluss side, at least they used a lintel

 

[aconnor2]

remember that the outer skin is normally non load bearing so the lintel only has to take the self weight of the bricks
the inner leaf takes the roof load and floor loads so it'll probably be fine.
if the steel went all the way to the edge of the brick it would be difficult to hide on an external wall given that you need 25mm of pointing ?
the allowance for corbelling is approx 1/3 of the width of the brick

Interesting to know what the SE says though

 

[noseall]

i,m glad you said 'normally' non load bearing, anconnor2.

i have worked on two properties in the last two years whereby the wall plate was bedded on the external course of bricks.

 

[aconnor2]

yeah i've seen a bow in a wall of a 2 year old new build house that you normally see in houses that are 120 years old because some body did that