Cracked concrete in garden office foundation

[bobbytici]

Hello everyone!

We've had a garden office put in and are unsure if what the guys have done will last or not.

There are already several cracks in the concrete and bits that are over hanging. I'm no expert at this but it doesn't feel like it's been done properly so would be great to get someone else's thoughts on this.

Cheers!

 

[George_engineer]

Yeah that's rubbish. They should be able to dig around it and repour.

 

[bobbytici]

Thanks for the reply George, appreciate the feedback.

So, would your advice be to repour around it? Is that likely to get it even at?

 

[john4703]

Contact the company that did the job and tell them to come and fix the problem.

 

[foxhole]

Looks like it was poured on soil and not a proper base.

 

[omph]

> Poured on soil it seems
> poor load distribution of the support beams, which will create stress points as you can see
> should have used rebar
> the concrete is exposed and no water barrier which could lead to rising damp
> are the support beams properly sealed ? last thing you want is for them to rot away
> the power (?) cable should be SWA not twin & earth

 

[mrrusty]

I'd be more concerned about the whole design of the base area. Water running down the cladding goes where exactly when it meets the wall bearer? To me it looks like it just runs in on top of the floor bearer and makes the structure wet.

Cladding should stand off from the base so that water running down the cladding is thrown outside the concrete base and can neither run in to the building or across the top of the concrete allowing the bearers to rot.

The power cable is a big cause for concern - it is not compliant and potentially hazardous.

Test it by putting a hose (on "shower" not "jet" to simulate rain) on it and see what happens. If the building leaks, get them back PDQ. If it leaks it isn't fit for purpose.

 

[bobbytici]

Thanks so much everyone for the advice and insight on this. It's really odd as this company came really highly rated on my builder.

Does anyone have an idea of what remedial work would be needed at this stage? Would the whole structure need to come and the foundations started off all over again?

 

[freddiemercurystwin]

My Builder? That explains EVERYTHING. Another victim of the dodgy builder websites.

 

[mrrusty]

Does anyone have an idea of what remedial work would be needed at this stage? Would the whole structure need to come and the foundations started off all over again?

It's going to depend where you are with respect to whether you have paid or not, and also what you paid. IMHO with regard to the base - it's not great (understatement), but I suspect that it'll probably be OK for years. The problem is if it's all paid, getting legal remedy is a world of hassle and pain with no guarantee of a result.

The more serious problem in my opinion is the wall structure design and watertightness around the base. If you didn't pay too much for a fairly skanky build, (i.e. you paid cheap and got cheap) it may be that the best solution is to add to it to make it better. If the main structure is solid, and there is a bit of a roof overhang, I think I might be tempted to over-clad it. Install a breathable membrane, additional battens, and additional cladding so that the water runs outside the concrete base. Dig a channel around the building and fill with gravel so the run-off has somewhere to go. If there's zero roof overhang to accommodate another layer of cladding, then that idea is a non-starter.

If you have a very big roof overhang you could even consider some additional insulation - depends on what you are using it for.

It does depend on what the rest of the build is like.

And please get that electric cable sorted - ideally get a sparks to run some steel wire armoured in.

 

[bobbytici]

It's going to depend where you are with respect to whether you have paid or not, and also what you paid. IMHO with regard to the base - it's not great (understatement), but I suspect that it'll probably be OK for years. The problem is if it's all paid, getting legal remedy is a world of hassle and pain with no guarantee of a result.

The more serious problem in my opinion is the wall structure design and watertightness around the base. If you didn't pay too much for a fairly skanky build, (i.e. you paid cheap and got cheap) it may be that the best solution is to add to it to make it better. If the main structure is solid, and there is a bit of a roof overhang, I think I might be tempted to over-clad it. Install a breathable membrane, additional battens, and additional cladding so that the water runs outside the concrete base. Dig a channel around the building and fill with gravel so the run-off has somewhere to go. If there's zero roof overhang to accommodate another layer of cladding, then that idea is a non-starter.

If you have a very big roof overhang you could even consider some additional insulation - depends on what you are using it for.

It does depend on what the rest of the build is like.

And please get that electric cable sorted - ideally get a sparks to run some steel wire armoured in.

So far, we've only paid about a quarter of the total due which I assume is probably going to mainly cover their materials and some of the labour.

I'm seeing the builder today so will bring up the point about the water tightness and definitely bringing up the electric cable point (already have done!). I was thinking of putting a water gutter around the rood and using a water butt (something similar to this https://www.diy.com/departments/war...-J4p9tcrY_sN6Lur65RoCe24QAvD_BwE&gclsrc=aw.ds) to help with the water issues.

 

[mrrusty]

Good - in that case do the hose test. let water run down the cladding as it would in heavy rain and see what it does - I do suspect it'll go where you don't want it to...

to me it looks like it will run in here

 

[Lower]

The wise man didn't build his house upon the sand....

That foundation needs sorting before even being worried about watertightness.

Personally, i'd be getting it taken down and the slab cast to a decent thickness. Then worry about watertightness on the rebuild.

 

[mrrusty]

That foundation needs sorting before even being worried about watertightness.

My large wooden shed stands on concrete lintels on top of just 100mm of wacked MOT. It hasn't moved a smidgen in years. Yes, that slab is not great, but it's a slab sitting on top of the ground. Unless the ground moves, it won't go anywhere - it's a glorified wooden shed - what's the worst that can happen? - pragmatically better to leave it now it's done. If it does move dramatically and needs taking down and redoing at some point in the future it's the same amount of work then as now. Unless the builder would be doing it all for free (doubtful) there's nowt to gain - pick your fights, and watertightness is a good fight to pick because it's binary - it leaks or it doesn't.

 

[erikT]

My Builder? That explains EVERYTHING. Another victim of the dodgy builder websites.

It's frustrating how some builders can get away with shoddy work.