Survey reporting structural movement. What to do....??

warwick2001

Good morning all,

Another day, another issue. Just got the Level 2 survey report back for a house we have put an offer in for (and accepted). The roof needs replaced/repaired, which we knew, but the surveyor found an issue with the main walls, and I quote:

"The main house walls are approx. 470mm in thickness stone faced externally and are assumed to be of rubble filled masonry construction. Stone walls are generally much thicker than conventional brick or blockwork walls. It should be noted that the walls may not comprise solid stone thought the complete thickness. The central core of the wall will probably comprise rubble fill and general debris.

There are signs that the property has been affected by structural movement as evidenced by the vertical cracking above the front door. This crack has been repointed and has cracked again, suggesting recent movement. There is also a crack noted to an internal wall. From a single inspection it is not known if the movement is structurally significant, but this should be investigated and expert advice sought."

I have taken some photos of this area:








I don't have a picture of the internal wall, but if I remember correctly it was a fairly small crack in the plaster, starting from the edge of a door frame in the back bedroom and running up to the ceiling. There are no other cracks in any of the other rooms, either upstairs or downstairs. The surveyor describes it as:

"I note a crack and wrinkling of wallpaper to an internal wall in the rear bedroom. This implies structural movement"

Given all this, and the photos, I suspect there may have been some movement at some point in time, but I don't know what to do next. Who would be the expert I need to look at it? Would it be a structural engineer, or would it be a builder? I know that sounds like a daft question, but looking at the outside 'crack', it looks to my untrained eye like a pretty shoddy repointing job that has shrank (possibly using cement mortar, not lime (the vendor's son is a builder, so it could have been a quick fix job)), thus exposing a crack as its pulled away from the brickwork whilst shrinking/drying out. The window to the left of the crack was installed approx. 2 years ago, could this have caused the problem? I'm not sure if the pointing repair job was before or after the windows were installed.

The internal crack is in the back bedroom, so does not mirror the front crack. It is also a 'completely' internal wall, so I'm not too bothered about this crack (maybe naively so) as its not a structural wall. This could just be normal cracking of lime plaster as it reaches the end of its life (could have even been a teenagers bedroom, and the door was slammed many a time causing the crack...). The surveyor noted that some of the ceilings also have cracks as well, and stated:

"Ceilings are of lath and plaster construction. Lath and plaster ceilings of this age will have limited life and be prone to loss of key and eventual collapse. The durability of this type is dependent upon the joint strength between plaster and lath. Some cracking is evident. This will deteriorate with age etc...."   

so we have added getting the internals re-plastered as well to the budget (using lime plaster, due to the age of the house, build in approx. 1880).


Obviously we really like the house, and it has great potential to be a lovely home, but not if the side of the house is gonna fall down. What are peoples thoughts? Does this sound like the normal doom and gloom of a surveyor, or are these issues genuinely a 'walk away from the house, and never look back' kinda thing? I appreciate you good fellows are just looking at a few pictures, and a few words from the survey, but initial thoughts would be great.

Many thanks

sevenhills

What has caused the crack, are there old mine works or is it due to the type of soil, is the land level, trees close by?

warwick2001

sevenhills said:

What has caused the crack, are there old mine works or is it due to the type of soil, is the land level, trees close by?

No idea what has caused the crack. 

As far as I'm aware, the surveys that came back to my solicitor haven't mentioned any coal mines, but I will check on that, good idea, thanks. I don't think Penrith was a mining town, so I suspect this is unlikely. Having a quick look on a map dated 1888, there are no mines in the locality.

There are no trees close by.

The house is on a slight downhill slope.

In regards soil type, not a clue. The house been there for about 150 years though, so I'm assuming its not anything unusual. Most of Penrith will have been built on similar soil I would have thought.

stuart45

An SE would be the one to ask. There isn't much of a tie for the gable wall into the front flank, especially in stonework with an almost straight joint between the frames.

Annemos

Good morning. 

Out of interest, you can get a rough idea of what soil you are on using the attached link. (British Geological Survey.)

If you click on the top right button, you can enter your postcode and look at the top layers and the bedrock.

(I agree with stuart45, a SE is definitely the one to consult for this type of thing.)


https://mapapps.bgs.ac.uk/geologyofbritain/home.html?&_ga=2.211478869.1527973533.1636974952-1456892645.1636974952

warwick2001

So, thanks to @Annemos , the superficial surface is 'Till, Devensian - Diamicton', and the bedrock is 'Penrith Sandstone Formation - Sandstone'. 

I have no idea what any of that means, but if there's a geologist out there.....help?? 

warwick2001

stuart45 said:

An SE would be the one to ask. There isn't much of a tie for the gable wall into the front flank, especially in stonework with an almost straight joint between the frames.

Thanks Stuart. Is this something that can be fixed within a sensible cost i.e. couple of hundred pounds, or are we looking at a few thousand? (ball park figure)

stuart45

It really depends on what's causing the problem. 
Modern houses have lateral restraint straps that add strength to an unrestrained wall, but they can be retro fitted if needed.
Do the stairs run up along that wall?

Annemos

All I know about this is the following Warwick, in general terms. 

Clay Soil: in a drought trees can suck the moisture out from the clay under the foundations and cause Subsidence. Tree removal, maintenance etc is a remedy in about 90 per cent of the cases, I think. 


Sandy soil: if there is a water or drains leak, that can wash the soil away under the foundations and cause Subsidence. Then the leak would have to be found and dealt with. 



I think only a SE could advise you if your cracking could be due to a foundation problem due to Subsidence. Or whether it is something more to do with the ties or the window fitting etc. 

When full investigations do have to be done, they might have to do boreholes to check exactly what is under the foundations and how dry it is etc. And drain surveys. 

warwick2001

stuart45 said:

It really depends on what's causing the problem. 
Modern houses have lateral restraint straps that add strength to an unrestrained wall, but they can be retro fitted if needed.
Do the stairs run up along that wall?

Floor plan shown, with location of the crack:

stuart45

It may have joists going into the wall which help restrain it. If not an unrestrained wall tends to do this.
These can help. Wall Ties | Lateral Restraint | Twistfix