Footings Depth before building regs visit??

[Ant4300]

Hello all,

I am building a double garage in my back garden and have dug out the trench footings ready for building regs to come and have a look at.
I was hoping they would give me a bit of advice over the phone before I arranged a visit but they said they wont give advice without seeing the site first. Anyway before they come round I would just like some comments from you guys regarding whether I am somewhere near with the footing sizes.

The garage is will be 2.5m eaves height with pitch roof. Single skin block construction. So far my footings are 400mm wide and 600mm deep from the main level of the garden. I am not planning to use any rebar, just gonna put a layer of hardcore in and pour roughly 500mm depth of concrete. This will put the top of the concrete just below the main level of the garden so I can soil over the top for frost protection.

Does this sound ok to you guys? I am not a builder by trade and have got where I am simply from google results.

Thanks in advance for your help.[/quote]

 

[noseall]

have dug out the trench footings ready for building regs to come and have a look at.
So far my footings are 400mm wide and 600mm deep from the main level of the garden. I just gonna put a layer of hardcore in and pour roughly 500mm depth of concrete.

Woa boy, hold on there!

Do not put hard core in trench footings.

A standard dig is 1m down from ground level. If the ground is unsuitable at this depth then go deeper. The current job we are doing, I had to go down 8 feet!

 

[Ant4300]

Sorry I should have mentioned, I have hit a layer of clay at the depth I am currently at. Seems pretty solid, would this be ideal for laying concrete on?

What should I be putting under the concrete instead of hardcore?

Thanks for the help so far.

 

[freddiemercurystwin]

You don't put anything under the concrete, it needs to sit on virgin undisturbed earth.

 

[tony1851]

As the above two, don't put anything in before the concrete.

At 400, your width is OK for single skin and short-span roof, but 600 depth may or may not be OK. The clay may be good and firm, but can be subject to shrinkage if the dig is too shallow.

Are there any trees or shrubs nearby? Be prepared for the inspector asking you to go just a little deeper.

BTW, is your garage big enough to need a Building Regs application?

 

[Ant4300]

Thanks guys.

I think I will just get building regulations out and see what they have to say. If they say go deeper then I will just go deeper, was just trying to save my back lol.

Thanks for the pointer on the hardcore though.

 

[ban-all-sheds]

I think you should have:

1. Put the time & effort into learning how to construct foundations before just digging a trench which you hoped would be OK and thinking you should put hardcore in it.
   
2. Done a full plans application rather than a building notice.

I am not a builder by trade

Indeed not, but you are carrying on as if you were, not seeming to think that ignorance should in any way be a bar to you just diving in and starting work.

 

[cjard]

Thanks guys.

I think I will just get building regulations out and see what they have to say. If they say go deeper then I will just go deeper, was just trying to save my back lol.

Thanks for the pointer on the hardcore though.

the process is quite simple. You're paying good money to a man who will tell you hoe to build it and sign it off when you do as he says. You don't additionally need the two pen'orth of someone on an internet forum

if you want to save your back hire a mini digger

 

[freddiemercurystwin]

the process is quite simple. You're paying good money to a man who will tell you hoe to build it and sign it off when you do as he says.

Technically BC have no obligation to advise whatsoever, it is for the builder or whoever is doing the work to propose adequate solutions.

 

[cjard]

Yeah, but have you ever known a BCO tell you to get stuffed, when you said to him "how would you like me to lay these foundations out, in terms of depth, width, slump etc" ?

Even the council ones aren't that unhelpful

 

[jeds]

Why do you need building regulations for a garage?

 

[Ant4300]

I have submitted a planning application as the garage is 6m x 7m. To be honest I really don't know if I need building regs approval but for 130 quid I thought it cant hurt to have the input of an expert along the way.
They may ask me to go a bit deeper then due to shrinkage risks with the clay.
Was just after a friendly nudge in the right direction which most of you have done, thanks guys.

 

[tony1851]

I have submitted a planning application as the garage is 6m x 7m. To be honest I really don't know if I need building regs approval but for 130 quid I thought it cant hurt to have the input of an expert along the way.

You would have needed Building Regs anyway as it's over 30 sq. m.