Tolerance for the footings

alexp79 · Nov 30, 2018 7:27 pm

Can the house stripped footings (for the rafted slab) go under slope (sideways)?

My engineer designed stepped footings, but the concreter says that he can make them sloped instead? The expected shortfall can go up to 0.5 m over a 6 meter distance.

It it a normal practice?

He tells me it is a normal practice for the sloped sides and that concrete block layers will be able to even out slabs by cutting the blocks which will be attached to the sloped footings and poured thereafter. He says that going for sloped footings instead of steps will be save me so much money.

I am not convinced at all and my engineer is telling me that I should not be doing them that way.

Is anyone doing stripped footings that way at all or it is just a bad concreter?

StructuralBIMGuy · Dec 01, 2018 7:11 am

Alexp79
I hear that excuse from bad concretors all the time, Tell him to read the engineering drawings and if he screws up it's at his expense
How does it save you money, when the mason is going to charge you extra to hand cutting all the set out blocks?
Avoids problems being passed on to following trades to fix. hth

building-expert · Dec 01, 2018 12:14 pm

It’s just a shortcut for the Concreter
Tell him “You are fired!”

alexp79 · Dec 02, 2018 10:06 am

Apparently, in Sydney they are building most of the houses on slopes with footings like this (the concreter showed me photos of his other projects) and then use bricks or concrete blocks to even out the levels before pouring the slab. They are not only sloping them in one way, but in both directions and do not even screed properly, so when it rains, the water simply stays in the uneven areas and you can clearly see it. The footings look like waves.

They say it saves a lot of costs on earthmoving, although I do not completely understand how (as you would still need to back fill them and form the pads, anyway).

I am not an expert, but I always thought that concrete and bricks are not good with shear forces at all and that the structure built over sloped/uneven footing with have this shear forces in place. When I asked, they tell me - well, we just will add some horizontal reinforcement to hold things and this is it!

It is unbelievable where this industry is moving to.

I am not going anywhere with this concreter.

aussieta · Dec 02, 2018 11:15 am

save $1000 on concreters costs
spend extra $2000 on brickies costs
and have a poor quality job as well
hmmm which way to go

building-expert · Dec 03, 2018 5:39 am

There is no saving, just shortcut for the lazy concreter, there is no excuse for not following approved drawings and poor workmanship.