New Crack in 46 yr old house

[tijay]

46 year old brick house, what would have cause this crack in the bricks, it has only just happened in the couple of weeks, is it serious or nothing to worry about, there dosent seem to be any cracks in the foundation blocks, Thanks, Tina.

 

[KenGMac]

tijay, good evening

And as this is your first post welcome to this mad house of this Board?

Firstly, all external cracks are not necessarily the [dreaded] Subsidence.

At first glance, the crack has been occasioned by so called "Thermal or Moisture movement"

If possible? can you post an image of the entire elevation where this damage has occurred please?

Why?

Because if the elevation does not have a built in [constructed when the Property was built] Expansion joint / s then the crack damage can be explained

Given the properties age then it is unlikely to have adequately designed Expansion joints.

What elevation is the damage on? possibly South?

What is probably occurring is that the brickwork on the elevation is heating up, there is probably no Expansion joint, the brick under stress can / will crack at a "Vulnerable" point, below a window.

The brick above the base course will slip / slide on the DPM that is sited between both of the above [google DPM??]

Ken.

 

[^woody^]

That's a typical thermal crack - ie shrinkage.

Common after periods of either dry, hot, orwet weather whatever the building's age.

But it might be a trick of the lens, but it does appear that the brick work each side of that crack is running up towards the crack. Have a look and the wall from one of the ends and compare the joints of the bricks and blocks for level.

 

[Newboy]

If the OP is actually in New Zealand then this might be a possible cause?

https://www.geonet.org.nz/earthquake
http://www.independent.co.uk/news/w...nd-southern-ocean-us-geological-a7956491.html

 

[JohnD]

some NZ houses are not built the same way as UK houses

It looks to me like the foundation is hogging (coming up in the middle, or down at the ends)

Sometimes that can happen under a window opening due to weight distribution over soft ground.

A wide view pic of the whole house might be useful.

Include any trees that might be drying out the ground, or any drains or waterpipes or gutters that might be leaking.

 

[tijay]

Hi thanks for all the replys, I think its the way the photo was taken, I will take a wide angle photo later when im back there, yes I am in New Zealand but im in northland and we dont get earthquakes up here, will post another photo as soon as I can, Thanks, Tina.

 

[KenGMac]

Good evening again, [ my time Zone?]

Despite what JohnD posted about "Hogging" I have reservations, in that I do not believe that "hogging" has or is happening? Sometimes referred to as "Heave". On a technical aside? i once attended a meeting of Insurance Subsidence Specialists, in all some 28 / 30 people all but one had seen this mythical beast "Heave"

Why, because in the image posted there is no cracking below what I am presuming to be the DPC, on the top of the white base blocks???

I have seen dozens of such cracks OK up here in Scotland, and as such I am with "Woody" and believe that the crack is thermal?

As an aside have you had a hot Summer? [cannot recall what that must be like -- Scotland Etc?---]

Look forward to next set of Images?

Ken

 

[tijay]

Ok, I went over to the house this morning and took these photos, sorry about the scaffolding, house is getting re roofed, also I think that the crack may have been there for a long time as it has paint in the crack at the top, we have only just brought the property and didnt see it when we brought it, but I would still like to know if its anything to be worried about, thank you, Tina

 

[^woody^]

Middle of the wall, only the bricks, most likely a thermal crack then. Probably not a concern, and especially not if not affecting the internal room.

Repointing and new bricks may be obtrusive, so sealing with a clear silicone or polymer may be best.

 

[KenGMac]

tijay, good evening [my time clock]

As Woody the crack is simply thermal, meaning when the brickwork heats up in the Sun, it expands, when at night or in Winter the bricks contract, the amount of such expansion and contraction will depend on the constituent make up of the bricks

As your external crack is about 50% along the length of the wall is itself indicative of thermal movement, as an aside modern practice [over here] requires new build brick walls to have a purpose built, designed, expansion joint built in at about 6.m apart, such expansion joints allow the thermal expansion of the brick to do just that, which is to move but not cause cracking elsewhere in the brickwork.

Ken