Can I add to my foundation

[ukdodger]

I did a silly thing. Forgot to make my foundation for a single brick wall wide enough at the end to accommodate a pillar. It's a 1 1/2 brick pillar and needs another 130mm of foundation added. How bad a problem is this. Can I simply dig out the 130mm and lay more concrete up against the existing concrete. If so is there a right and wrong way to go about it?

Thanks

 

[Static]

No just adding concrete will crack away and be pointless..

You need to bond the new concrete to the old normally done with dowels resin'd into the old, but with only 130mm to add this will be difficult as there will not be enough space to bond the dowels into the new. Even with L bars it would be tight..

What is the wall for? If its some form of critical support pier then you may also need to underpin the foundation.

What about breaking out the concrete and replacing a section?

 

[ukdodger]

No just adding concrete will crack away and be pointless..

You need to bond the new concrete to the old normally done with dowels resin'd into the old, but with only 130mm to add this will be difficult as there will not be enough space to bond the dowels into the new. Even with L bars it would be tight..

What is the wall for? If its some form of critical support pier then you may also need to underpin the foundation.

What about breaking out the concrete and replacing a section?

Thanks for the reply. It's a dividing wall about 7ft long and 5ft high. At one end it abuts the house at the other (shown) it ends in a pillar. As you can see there isnt enough room for the 1.5 brick pillar. Unless I can terminate the wall in another bond, and I cant think of one, it looks like I'm stuck with digging it up. A real bummer!

 

[Static]

Ok when you say dividing wall i would assume you mean garden boundary wall.. not something supporting a roof or floor etc

 

[ukdodger]

Ok when you say dividing wall i would assume you mean garden boundary wall.. not something supporting a roof or floor etc

Yes that's right.

 

[Static]

Ok, well you cant be that far off fitting it on there as it stands.. try laying it out to size you need.. a small overhang (ie upto say 15-20mm) would be ok..

Alternatively it may be simplest to remove the last say 500mm of the footing and redo it larger dowelled back into the first pour..