Structural problems

[bassanclan]

I'm building a garage.

The foundations were 1.5-2m deep mass fill gen3 concrete, no trees nearby.

 

Left hand wall outside course has significant cracking appeared since Christmas. The wall below dpc has also bellied out.

No cracks on the inside course, or visible foundation concrete

 

I've got two theories,

One being that water is undermining it causing one side to drop or slide away. (This area is very wet with a lot of standing water having to be pumped off)

 

The other being that the lean mix cavity fill has expanded and pushed out the brickwork. (The mix was full of all sorts of rubbish and old cement, slc, dot and dab adhesive, skim etc)

 

My thought is to try and fix it with helical bar and replace the worst of the broken blue bricks?

[Mr Punter]

The foundation will only be a good as the soil it bears on and I suspect that they may have been poured onto soft mush rather than stiff clay.  Did BC inspect the trenches?

[bassanclan]

Yes the building inspector did inspect the trenches, he missed his initial appointment meaning the concrete pour had to be cancelled and another slot was booked, so the trenches left open for 4/5 days.

 

I wasn't there when it was poured, so I don't know how soggy it was underfoot, but there is no cracking in the foundation concrete

[Temp]

1 hour ago, bassanclan said:

The other being that the lean mix cavity fill has expanded and pushed out the brickwork. (The mix was full of all sorts of rubbish and old cement, slc, dot and dab adhesive, skim etc)

 

Given no cracks in the foundations I think that's the most likely theory. Do the cracks even go down to the foundations?

 

Another possibility might be issues with the mortar. Laying bricks when too cold? Does it seem hard or can it be raked out too easily? 

 

Not sure what to recommend. I suppose you could remove cracked bricks and replace. 

 

 

 

 

 

 

 

[twice round the block]

8 hours ago, bassanclan said:

 

In this final photo what is the build up of the footings as it looks like you have 1 course of blocks, then 1 course of face bricks followed by another course of blocks then 4 courses of Staffordshire blues. 

 

On one of the other photos it shows 10 courses of Staffordshire blues 

 

Why?

Are the blocks concrete? 

Why weren't they laid flat if there a build-up from the footings? especially if it's a garage made using single skin with piers inside.?

Edited February 1 by twice round the block

[bassanclan]

It is 100mm cavity build, hence my concern about whether the lean mix might have expanded and pushed out those few courses.

 

Some blocks are below the blues because they won't be seen after surrounding path it built. They are dense 7n blocks, some are laid flat, to make up for a bit of unevennesses of mass concrete footings.

 

Different soil levels around the site mean there is 10 course of blue engineering in some areas and only 4 in others.

[Russell griffiths]

Definitely looks like a cavity problem to me freezing water between the cavity fill and inner and outer leaf pushing the outer brickwork apart. 

[Canski]

Given the quality of the brickwork was it the same builder who filled your cavity with all the left over materials on site ? Just how high above ground level was the cavity filled ? 

[Brickie]

I’m not so sure-a straight crack through 5-6 courses of blue staffs? What were the temperatures during the cavity fill? (Including overnight)

 

Edit-just had a closer look at the photos-that first bed joint above the blues looks either frost damaged or they’ve used a s**load of Washing up liquid as a plasticiser. 

Edited February 2 by Brickie

[twice round the block]

 It's  nice to see a tidy site that obviously reflects the quality of the workmanship that has gone into the build.