Steel for Strip Foundation

De_man

hi

I'm getting conflicting information with regard to the type of steel
required for a strip foundation for 1.5 Storey with a large footprint.

the main floor shall be A393 Mesh which is fine and that complies with
the building regulations, however i can't find any reference to the
steel required or minimum requirements for the actual strip foundation
itself. even the construction manual doesn't offer any advice.

i've been given various suggestions to use both 10mm and 15mm in order
to distribute the load, with particular attention to the corners
I reckon 10/12mm would be fine, using 4/5 lengths each separated by 150mm or so for the external foundations (900mm)

Would be grateful to hear any opinions on this one



a pint of plain is yer only man

muffler

Why not use the A393 in the strip found if the ground conditions are reasonable.

I take it you propose to reinforce the sub floor with A393 but I would think thats a bit much but then again better safe than sorry

De_man

hi muffler

the conditions on the site are pretty good, i was going to use the A393
in the strip as well as the sub floor, with lengths of say 12-15mm steel put
in for good measure.

I know i'm taking it to an extreme level but for the sake of the couple of euro i'll put in just in case it decides to go anywhere:)

As always, thanks very much for the information we should be breaking
the sod tomorrow (finally)



a pint of plain is yer only man

muffler

Yeah, you're right. For a hundred or so extra euro you could throw in a couple of 12mm bars. I'd put 2 extra bars round the corners and extending 1200 in each direction and also 3 or 4 bars below the chimney stack.

Hope you have a digger lined up for the digging - spades are not as good as they used to be

Good luck with it

Johnniep

I would always place a layer of A393 mesh in the strip footings. One thing that is ofter overlooked is the cover to the steel. Its all well and good putting loads of steel in your founds but if water can get at it and corrode it away than you may as well leave it out. You should always give rebar 50-75mm of cover in footings.

The A393 in the floor slab seems like a bit of overkill to be honest. As long as you have good ground conditions, you can do a ground bearing slab with the mesh (typically an A142 mesh) serving as anti-crack steel only. But in this situation, your hardcore and compaction of it is vital!!

Finally, all steel should be lapped at the joints, typically 300mm for A142 mesh and 450mm for A393 (45 bar diameters!).

Hope this helps.

John

Viking House

What kind of build are you doing?

De_man

Muffler & Johnniep,

thanks very much for the info that helped me out a lot
i'm not too worried about the rest of the house (except for roof) it'll get done
but its the foundation and the Radon barrier that has to be right, i don't mind spending a bit more to make sure its sorted hopefully i'll be here for a few years


viking house
From what i've seen around being built its a fairly standard self build
an L shaped 1.5 storey (7.5M height), very roughly 60X30 with a sunroom, then L at the back, going back 20 X 28


Thanks again for the info my shovel & pick axe are calling:D


a pint of plain is yer only man