Worrying small crack?

[toptec]

Am Refurbing a 1961 bungalow. Brick and block, 60cm cavity.

Floors are part wooden part concrete.

Have had to remove a woodworm ridden floor and then found smallish interior crack

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This runs from the blockwork at the bottom into the corner and then up to the ceiling

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On this exterior wall are some repaired cracks that run from the corner of the garage half way down the wall

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About 15-20 feet away is a large fir tree

View media item 890 Which will be removed in time.

Question should I just repair/fill the cracks and monitor or is it, in your experiences, something which is symptomatic of something more serious?

And I did have a survey done - No mention of exterior cracking but interior was obviously papered and painted over

 

[^woody^]

The first suspect ( ) would be the rainwater drain - were the drains checked?

The internal crack looks old, and as there does not appear to be any directly corresponding external one, so foundation movement at the corner seems the least likely.

Also as it was not showing through the wallpaper, then it may be an historic crack. But if the surveyor missed the external crack, then he may have missed broken wallpaper too

The external cracks don't seem to be indicative of foundation movement either, and seems to be more likely lateral or thermal movement. Although there seems to be some mortar smudged along the crack, it can't really be said to be a repair.

The second suspect is the tree, but the cracks seem in an odd place and don't seem to be root related.

Monitor it for a few months, and if it opens then get the drain camera surveyed.

If it progress over 12 months then it may be tree related, but it depends on how the crack develops which will indicate what is moving

 

[toptec]

Many thanks for that Woody. I hadn't considered the drainpipe as a possible perpetrator( ). All the other downpipes on the property go into clay pipes through to soakaways. Two of those have caused problems and they have been dealt with.

I was thinking of applying filler to the internal cracks and see if it remains as it is.

Any suggestions for the external cracks? Is it worth raking and filling with a mortar mix? Then keeping a watching brief? ( )

 

[^woody^]

Gouge it and fill it, caulk it or (my preferred) hack off plaster to about 3" , fit some mesh or wide scrim across the crack and then replaster.

Externally, I would leave it to see if it is moving, but then only repoint if the wall is stable. For the fine cracks in the brick, replacing the brick may be too obtrusive (and look like there was a worse problem than there is) so I would run a fine bead of clear silicone into it, and then leave it or if you like, blow some red brick dust into it

 

[chessspy]

Hi, toptec,
as your house is 1960s, then the foundations are probably not as deep as they might be, and what you have here is fairly typical, a bit of movement, caused by ?? tree?
I wouldn't worry too much, as it doesn't look like much.
there are some little plastic thingys that monitor the movement, if any in a wall, they consist of two pieces of clear plastic with a mm grid on and you glue them to each side of the crack and see if they move.
I personally wouldn't bother, but if you want to be reassured that the wall isn't moving then contact a local civil engineer and beg one off him, glue it on and monitor it over the next few months.
I've lived in houses built in 1880s with 4" on bulge in the gable~~(that symbol means what the cuff)
chessspy

 

[toptec]

Good idea about the scrim tape. And the gap indicator. Will sort it out this week.

By the way my wife thinks the woodworm are using the crack to come in and out of the house!!!!!!!!!!!

 

[chessspy]

FOMPLOL!

 

[^woody^]

The "little plastic thingys" are called tell tales

But as all buildings move, they are not going to tell you anything unless you know what to look for.

You can just look at the crack and note is it gets bigger, longer, widens at top or bottom, or the wall each side shifts out of the vertical plane. And its only a problem if part of the wall continues to move in one direction over 12 months or more.

If the corner is moving, I'd expect some corresponding cracking in the render on the front elevation too

 

[toptec]

Cheers

Ten Four.

 

[chessspy]

Hey, woody, I knew that1,
anyway, I just built em, and the ones I built didn't move anyway.

 

[chessspy]

You can just look at the crack and note is it gets bigger

yeah, i'm married, I can groove with that.

 

[chessspy]

You might consider insulating between the joists whilst you've got the floor boards up, it saves a lot of heat loss.

 

[toptec]

I thought doing that would interfere with the ventilation from the airbricks?

 

[chessspy]

Hi, toptec.
Not if you staple garden twine to the undersides of the joists at about 1 foot apart, and then lay the 100mm fibreglass brtween the joists on the string. (I bought an industrial stapler from B+Q for a fiver, with plenty of strong staples included and stapled each time twice, as you can't actually see what you're doing on the underside of the joists)
It really works, when I did mine I also cleared our the debris from the earlier work and made sure the airbricks were clear both inside and out.
You could also consider putting some fine mesh over the airbricks to provide a vermin barrier, (mice can get through a suprisingly small hole)

 

[Shytalkz]

Minor levels of movement; as Woodster says, possibly the rainwater pipe either blocked (by root infestation - looks like there are some other leylandii nearby?) in the ground, or broken. Worth digging out and replacing in plastic to be sure and also to be able to forget about in the future.

External cracks suggest something different, although the (poor) repointing doesn't seem to have reopened to any significant degree.

Replace drain within immediate vicinity of the property, repair cracks to let it self-monitor, before deciding if anything else more extensive in terms of remediation is required.

These comments presuppose a predominantly granular soil. If you're on a clay, it might be due to the tree sucking moisture out of the ground; if that is your soil type, be wary of the respective ages of property and tree. I'm no tree expert, but that one looks to possibly be at least as old as the property. If a tree is older than a property its removal can result in heave of the structure.