Opinions wanted on cracks in 1920's semi wall

[MilkyVampire]

Hi ladies.

Finally found a house we really like after selling last Autumn and moving in with my parents, in order to keep our first time buyer.

Been in a few best and final offer situations but lost so the market is moving fast and good properties get snapped up. There's been a poor selection of family properties on with the odd gem with extension and newly done out, which had always gone best and final. We've considered so many conditions of house but the one we have had an offer accepted on and is 'off the market', is done up, but for a last bit of effort required on the hall (skimming), porch and drive.

All good then... accept for some cracks in the back bedroom, adjacent to the massive rear window, going under the picture rail and a similar crack on the landing (same wall as bedroom crack, different place).

There's also a couple of cracks above the kitchen door and else where on that wall. An awesome extension was added and old kitchen demolished in 2016. Then there are a couple of cracks in the hall going from upper floor to lower but just part of it. All windows and doors open and close fine.

I've instructed a full building survey for £600inc vat for next week sometime and just hope it isn't subsidence. House was built 1927 and adjacent semi has some narrow cracks at diagonals to the UPVC window frame, as do other semi's either side. It has a river over 200m away and adjacent fields have done surface flooding at the mo but property hasn't flooded.

I've seen the vendors previous Homebuyers survey from 12 years ago and it mentions historical movement that is no cause for concern.

Full architectural drawings are available for the extension and it has newish wiring, RCD, and lots of high end features like granite worktops, engineered wood flooring. The owner has obviously spent a lot on it. I'm saying as, surely you wouldn't invest loads on a house that was falling down. I checked re insurance too and they are paying a reasonable fee.

Here are some pics. Have any of you had similar cracks in your house?

Sorry having difficulty adding images

More pics

The render on the external picture looks in bad condition and need replacing. If there are no cracks in the brickwork below, I wouldn’t worry too much. The other cracks look like shrinkage cracks. These are normal and they are not very big. If they are replicated on the outside then there is w concern. If they are just internal plaster shrinkage, which is likely, they can be filled and redecorated. However get expert opinion if you need it.

We're in a house about 10-20 years older than yours and tiny hairline cracks appear all the time- we probably fill them every year or two. Old houses, especially those built on clay do just move, especially after a dry, hot summer. With my house I'm of the mind that the house has been there for over a hundred years, and hasn't fallen down yet, so its probably ok! Having said that to cover yourself do make sure you get that full structural survey, and read up a bit on what should set alarm bells ringing. From memory some of the things you need to look for are a large tree growing very nearby (the rough rule of thumb is that the bit you see above the ground is mirrored by a similar sized root system under the ground. This could cause problems if it comes into contact with the house's foundations). Also, if you can see the same crack both inside and out (rather than just on an interior wall, say), and also cracks that are thicker than a 10 pence piece.
Also, with houses I've been interested in before I've found that with a bit of internet digging you can find out if subsidence is a problem in a given area. For example with one property I found details of major building works on a block of flats on the same road to correct subsidence- I chose not to proceed with that one!

1920s semi here. We have similar cracks round upstairs bay window. We were told (architect,surveyor,builder) it's to do with replacing the window and not a cause for concern ie the house isn't falling down!
I must admit that when the old windows were taken out it was a massive job to get the frames out so that must have had an effect on the immediate surroundings ie some movement.

I'd be more concerned about any flooding risk tbh, but if that's not really an issue I'd go ahead.

Thanks so much for thoughts so far! Keep em coming!

No houses fall down so really that’s not a criteria to judge cracks. If they are through the bricks and mortar and you can see clear evidence of cracks snaking vertically up the building it’s possibly subsidence. As you have not photographed this, I’m assuming you don’t have cracks in the bricks.

Houses can suffer from heave on clay. This is when the clay is waterlogged and swells. It pushes the foundations upwards and the walls go outwards. At it worst, a house like this could be demolished as its beyond repair. So not fall down exactly but a fairly dire outcome. You probably don’t have this op so don’t worry.

These are not historic cracks at all unless they have never filled them in from previously. That house is moving and I wouldn't touch it with a barge pole

Don't waste your money

Something is going on but the vendor has said that these appeared since the kitchen utility extension was put in in 2016 and 800mm pilons where driven in for its foundation. That and removal of the WC wall to the bathroom just outside this room could disrupt the plaster. I mean a big sledge hammer is going to do something I would expect.

I'm my last house we sanded the floorboards in our master bedroom with a big belt sander and the vibrations from that saw hairline cracks appear in the original ceiling below (1906 house). So that is why we are living in hope and anyway, the building survey went ahead yesterday so we're £600 into things now.

We get the report Tuesday or Wednesday next week so I'm pretty nervous. I'll update with the findings.

P.s. there's no way to see if the cracks go through the wall, as it's had external cladding installed at the time of the extension, (it matches the extension from 2016). Neighbours I've spoken too haven't had worries about subsidence but there are evidence of hairline cracks on their houses near to the very large windows, which have been replaced from wood to UPVC in both their houses too.

Anyway, we'll see.

Following with interest as we bought a house that had been underpinned for subsidence 35 years before and has a few interesting cracks In one room despite our full survey coming back ok and no monitoring of movement or further repairs needed. We are on clay and a lot of local houses have experienced movement, mostly settled and now historical. It seems quite accepted round here as normal. We love this place but I do worry.

There is differential settlement between new extensions and older buildings. It could be this. These cracks are not huge. 800mm foundations are not deep for clay. We have twice that. However there can be movement between new and old so I hope it’s not more than this. Are the windows out of shape with cracks beneath them? What is the external cladding? What form of construction is underneath it?

These are not ceiling cracks..they are vertical and diagonal in places. Why take on a house with suspected subsidence? If you must get a structural report which will cost and I bet will not reassure you

The op has no idea if it’s subsidence or not and neither does anyone posting here. We have vertical cracks where a later addition to the house meets the Victorian part of the house. DH is a Structural Engineer and it isn’t subsidence. It’s differential movement between old and new buildings. It’s nothing to worry about in general. The cracks are not large and ours are nothing to do with ground conditions. It’s about how the walls have moved independently of each other. There is no evidence on the outside at all.

are there any drain lids (drains) near the house? Make sure you ask the surveyor to check these specific cracks & if possible get into the attic & check roof space -

You should get a Structural Engineer. Surveyors won’t risk getting it wrong.

I was a bit hasty earlier. It could be subsidence but you have to take into consideration the extension joining the original building too. Leaking drains could cause heave. A spreading roof could push walls out of shape. So I hope you get some answers.

Hi all! Got the report back and have been going round saying it's bad and freaking out but really I'm not sure. I mean there are condition rating 3's on a drainage issue and to check joists where there is a slight buoyancy but I'll paste the main concerning bits here and welcome your thoughts...

"The above-mentioned cracking in the lounge and master bedroom walls is indicative of a degree of uneven foundation movement at the intersection of the rear wall with the side wall of the extension. This is likely to have been caused by initial consolidation settlement of the foundations below the extension side wall, which is bonded into the original rear wall, and by the load imposed by the masonry wall above the beam, which will be transferred onto the remaining main rear wall at both sides of the opening.

Any such movement is likely to have been exacerbated by rainwater discharging to the ground adjacent to the foundations via the overflowing rainwater gulley at the rear wall, which if occurring over a long period of time can cause a localised saturation of the ground adjacent to the foundations, thereby reducing the loadbearing capacity of the sub-soils. We advise that further investigation should be carried out by hand excavation of the sub-soils adjacent to the gulley to confirm this cause (the over-saturation of the sub-soils), in order that it can be corrected.

Following any necessary repairs to the below-ground drainage system, the sub-soils will regain their structural integrity as the moisture content returns to normal. However, as the internal cracking is likely to have occurred subsequent to the construction of the rear extension around three years ago, we cannot state with any certainty that no further movement will occur as a result of initial consolidation settlement, which usually occurs in the first ten to fifteen years after construction. We recommend that the fractures are monitored over the next three months to establish whether the movement has ceased. Once it is established that the structure is stable, repairs can be implemented as necessary. Condition rating 3."

Cont. from another part of the report...

"The rainwater pipes mostly discharge into clay or PVCu gullies, which are in serviceable condition on the whole and are holding water. However, at the main rear wall, the gulley between the rear bay and the extension is filled and overflowing, which if occurring over a long period of time can cause a localised saturation of the ground, thereby reducing the loadbearing capacity of the sub-soils adjacent to the foundations.

The above-mentioned gulley is a replacement component which we anticipate was installed when the extension was constructed in 2016/2017.
At the front corner of the extension there is a new sectional PVCu inspection chamber for the combined foul and surface water drainage system, which would suggest that the below-ground drainage pipe between the gulley at the rear wall and this inspection chamber has also been replaced. However, the position of the inspection chamber would indicate that the drainage pipe runs below the extension.

It is likely that the gulley at the rear wall is filled to overflowing because there is a blockage in the system, but we cannot completely rule out the possibility that the drainage pipe which runs below the extension is defective.

A drains specialist should be requested to clean out any blockage in the gulley, inspect the drainage system for defects and to provide advice on any further remedial action considered necessary, which will possibly involve lining the drainage pipe below the extension or re-routing around.

In view of the potential for expensive repairs to be required, we advise that this work is carried out prior to exchange of contracts. Condition rating 3."

And this section on the walls...

"Main walls
The main loadbearing walls are of solid brick construction approximately 240mm thick, finished internally with plaster. The external walls of the rear extension are of brick and block cavity construction, 320mm thick, dry lined internally with plasterboards fastened with adhesive. The main loadbearing walls were found to be relatively plumb and level when tested with a hand-held spirit level, and when viewed from the external we did not see any sign of cracking or separation indicative of any recent or significant structural movement having occurred. Condition rating 1.
...
"We did not see any significant defects to the internal walls in most areas, but in the master bedroom tapered diagonal cracking of 1mm to 3mm in width can be seen at the right corner of the rear wall and in the internal side wall at the left side of the chimney breast. Between these fractures, cracking of similar magnitude is evident at the under-side of the plaster coving.

At the position of a removed chimney breast in the lounge below, diagonal cracking around 1mm wide is evident in the internal masonry wall, and diagonal cracking up to 2mm in width is apparent in the plaster finish of the dwarf wall at the right side of the patio door. "