Vertical Cracking

[djsherly]

Hi guys,

I want to put an offer in on a house which I really like (it's for a PPOR) but I am concerned a little about some vertical cracking in the brickwork.

It probably isn't a great deal and the building report describes the crack attached at Cat 2 slight as per AS2870, and not considered structural.

It looks to me like thermal expansion (the pic shows the wall abutting the north face) but are these things really any great deal? There are a number of these through out the brickwork, but they're all vertical, and this one is by far the worst. most are hairline.

The house is 30yo so is probably due for a little remediation but do I have a lot to be concerned about here?

 

[Kristine..]

Hi djsherly

Actually, yes, I'd be a bit concerned. The cracks run through the bricks, not just the mortar joints, and this implies quite a lot of pressure on the bricks to cause them to crack.

As this is affecting the outer corner of the wall, this definitely implies that the strip footing has failed.

Failure of strip footings can come about from a variety of causes, the most common being moisture in the foundations / drying out of the foundations, particularly in clay reactive soils, and the effects of tree roots.

What type of vegetation is there within 5 metres of this wall, including on the neighbour's side of the fence? If there are lilly pilly or similar moisture seeking shrubs or trees, their thirst can have dried out the clay base causing the strip footings to roll. Even a couple of millimetres can cause tremendous pressure on the brickwork.

I have seen a house where this occurred, causing the brick wall to roll away from the house to a full arm's thickness gap!

No cracks inside the house, but the strip footings were irreparably damaged.

Cracking which follows the mortar joints is mainly due to the articulation joints perhaps being a little too far apart. Cracking through the bricks themselves would certainly warrant further investigation.

The roof beams and rafters should also be checked, as this pressure can be transferred through the brickwork to the timber framing of the house.

No: 1 Son was going to buy a very attractive townhouse a couple of years ago, but after we really looked at it we realised that numerous places in the brick walls - including high up under the eaves - showed signs of the walls being under pressure. Apparently there had been a large liquid amber tree in the front of the land at one time. The tree was removed just before the townhouses were built. As the soil re-hydrated this caused pressure on the footings, which transferred the pressure to the brick walls, which literally buckled a couple of millimetres horizontally and vertically.

There had previously been remedial work performed and the strip footings had been pumped with aerated concrete, but after much consideration we figured there were lots pf houses out there without all these problems so we kept looking.

We figured that the property had had nearly 4,000 hits on the website and had been on the market nearly eighteen months. If Son had wanted to sell who else would want to buy a property with potentially more problems of this complexity?

Have an engineering report done but be aware that once damaged it is very hard to make things right again. Of course, if you have any plans to extend the house out from this corner then you can fix the footings at the same time but do check for old creek beds, areas of fill, swamp trees, etc before you make a decision to buy.

Cheers

Kristine

 

[djsherly]

Thanks for the prompt response kristine. I really appreciate your input.

"vertical cracking was evident to several corners and
adjacent to windows, this cracking is due to brick growth
and horizontal movement, footing appears sound. The
worst of this cracking is classified as Category 2 Slight as
per AS2870 and is not considered structurally significant;"

"the cracking to brickwork is due to thermal expansion and
contraction. Such cracking is not uncommon in the
Canberra region. This is not considered a structural
problem and will probably open and close;"

This is what is in the building report - these are required before offering a house for sale in the ACT.

it also indicates that the roof line is true and straight.

I'm in two minds - apart from the issue outlined I really like this place.

I'll get further feedback from the compiler of the report and conduct my own investigations. I wonder if I should walk away now?

 

[thefirstbruce]

Like Kristine, I'd be concerned about disposability. Hard to disguise the cracks right through the bricks......unless you are going to render a whole wall and the corners....

Large trees with roots close to foundations, and poorly drained ground alternating through dry spells can crack footings and slabs nastily. These are problems better avoided. One of the advantages of buying a home 3-20 years old is you know the house is bedded in.

 

[TommyR]

Hi djherly,
from the photo imho I'd suspect the cause of your crack is most likely due to "brick creep" a characteristic particularly of lighter and softer burnt bricks where over a long period of time the brick actually expands causing pressures at junctions which eventually lead to cracks. This condition is usually avoided by the inclusion of adequate expansion joints during constuction to accommodate this movement - unfortunately 30 - 40 yrs ago the building code was not quite specific enough and it was common for builders to build long walls with no expansion joint included to allow for excessive expansion.
I'd suspect your building report is probably correct,in that it's not structural, and the house is ulikely to fall down, however the cracking is obvious and unsightly and would certainly deter future potential purchasers of the property given that it's appearance is unlikey to improve with time.

Tom

 

[geoffw]

Have a talk to the building inspector. He should be able to give you information about the seriousness of the situation.

 

[Peter Parker]

Hi djsherly

Actually, yes, I'd be a bit concerned. The cracks run through the bricks, not just the mortar joints, and this implies quite a lot of pressure on the bricks to cause them to crack.

If it's any consolation, these sorts of cracks are extremely common on the old 1960s 'six-over-six' apartment blocks around here.

People still seem to buy them - maybe they think the body corp will sort it out if it gets too bad.

Peter

 

[Indifference]

I walked away from a house in Lyneham because it had a similar problem. The issue I had was that IMHO I could not rule out further cracking occuring leading to damage that actually required repair. The potential repair costs were just another negative for that particular property.

I subsequently purchased a house nearly 40 yrs old in Chifley..... no cracking at all. Basically, it is a personal judgement call and the only one that will be out of pocket in the future if it gets worse is the owner.... I prefer to manage my own risk exposure regardless of what someone else 'thinks' to be the case. That way I sleep easy at night.

 

[djsherly]

Geoffw,

I did speak with the building inspector and has said that it's not out of the ordinary, he was adamant that it would not get worse.

I am not an engineer by any stretch and can only go by what professionals say.

Indifference,

what did the building report say about the cracks?

 

[WillG]

There appears to be a fence beside the brickwork. Is this fence dynabolted to the brickwork ? Could this be the cause of the cracking (dynabolts incorrectly installed ) ?

 

[djsherly]

I don't know about the fencing being an issue.

As I'll be potentially looking at this thing for the next five - seven years, what options exist to to improve the aesthetics of a crack such as this?