Hairline cracking due to thermal movement - how expensive is this to fix?

Annisele

Afternoon all

I'm hoping somebody can help me interpret a survey I've just got on a house I want to buy. I can't ask the surveyor about it until Monday.

I have no experience at all of surveys; I'm a first time buyer. On the one hand the survey makes it sound as though the house is about to fall down - it's absolutely full of faults - but it also says things like "the type and number of problems that have been identified are typical for a property of this age [early 1970s], especially where there has been a lack of overall maintenance", and "overall, the main enclosing walls appeared structurally sound". Those parts make it sound like it's probably not an irredemable money pit.

The house is an ex rental (vacant at the moment) and looks as though it hasn't seen a paintbrush in a decade. I don't want to buy a renovation project, but I'm completely OK with living with dated decor for a few years. I can afford to spend up to £10k or so on fixing anything urgent, but after that I'll have to either ask the vendor to reduce the price or pull out.

A lot of the "condition rating 2s" seem to boil down to "this thing won't last forever and will need to be replaced at some point", or "this wants redecoration/resealing/filling". Most of them are things I hadn't noticed myself, but they don't sound particularly worrying or urgent. There are a couple of places with blown plaster, a single cracked roof tile (cracked but still watertight), and a bunch of damage to paint and sealant etc.

The bit that does worry me is the walls. The "condition rating 3s" in the report were about gas, electricity, and the walls. I was very much expecting that the electrics wouldn't be up to modern standards - I was tipped off by the fusebox - and so I'm not shocked to also find that "the gas meter was located too close to the electricity mains". However, I didn't notice the cracks in the walls until the surveyor pointed them out. I think they're quite hard to see on the photos, but they are there.

The surveyor said: "It should be noted that the cracking has occurred to the south elevation. This elevation is prone to temperature variations and thermal movement, therefore, this would be prone to hairline cracking. Although there was cracking below the damp proof course, this was likely caused by thermal movement. It would, therefore, be advised to undertake repairs straight away to prevent further deterioration which could likely lead to more costly issues, such as replacement of the entire render covering. Condition rating 3."

I have no idea if fixing that cracking is a £1,000 job, a £10,000 job or a £100,000 job. Any guesses on that would be most welcome.

I'd also be grateful for any guesses as to what the surveyor means by "straight away". Presumably he realises I'm not going to be completing on the house tomorrow, and if he thought it was going to fall down between now and, say, the end of November, he'd have said so. But is "straight away" likely to mean "within a few weeks of you buying the place, understanding that that might not be for a few months", or "now, immediately"?

Many thanks!

stuart45

Can't see the cracks, but thermal cracking usually is above the DPC.
Don't understand the render bit, looks like face brickwork to me.

FreeBear

Cracks in the mortar joints are nothing to worry about as long as the are small (under 3-5mm in width). If the cracks propagate through bricks, that is an indicator of something more serious.

I have a 1970s extension, and there are a number of cracks in the mortar joints - Most are just under the flat roof and caused by heavy handed nailing of boards when the roof was recovered. Will repoint one day, maybe, if I can be bothered.

stuart45

Cracking in the bricks can also happen with thermal movement if the mortar is too strong.(stronger than the masonry unts).

FreeBear

stuart45 said: Cracking in the bricks can also happen with thermal movement if the mortar is too strong.(stronger than the masonry unts).

True. And the "bricks" can also crack if they are concrete imitations.

stuart45

Yes, concrete and calcium silicate bricks suffer from shrinkage cracking. Always worse when freshly made, often happens in boom times. They should have movement joints more closely spaced than for clay brickwork.
Clay bricks expand in the heat of the day, but contract at night which is when the cracks happen.

greyteam1959

A better picture of the actual cracks would be useful.

Annisele

Thanks all.

All but one of the bricks look fine to me. (The exception is on the corner of the house, and it looks as though somebody has taken a chisel to it and removed a cube about 1cm big. I don't know what the story is there, but it's about wing mirror height and next to the drive.)

There are cracks in the mortar, but on the south wall those cracks look pretty small - maybe 1 to 2mm. The south wall doesn't have any render at all, so maybe the surveyor made a mistake; I'll ask.

The cracks in the mortar on the west facing (front) wall are bigger, perhaps 2m to 4m, and there's one spot where there doesn't appear to be any mortar at all between the bricks. There is render on the west wall, and it has some hairline cracks in it. I'm less worried about that because the surveyor has rated it as a '2' rather than a '3'. The surveyor's explanation is:

"Stepped cracking was noted above the ground floor garage door to the front elevation and above the second-storey rear window opening. The cracking was hairline in nature and extended a few brick courses above the openings. The cause of the cracking appeared to be the likely result of inadequate support provided during the removal and installation of the replacement window units.
As it could not be determined if there was any active movement involved around the affected areas, it would be advised to monitor the cracks for signs of movement over a period of a few months. If further and more progressive movement is identified, these may require additional repairs. Condition rating 2."

I interpreted that as meaning that it might be a big problem if the windows don't support the wall enough, but that it's probably a historic issue.

FaceHead

There is nothing you have said that is remotely concerning. On the gas and electrics, well obviously they aren't up to modern standards. Surveyors (typically) have neither qualifications in gas or electricity so will routinely put them down as 3, basically because they aren't in a position to say any better, and take a cautious approach. 

Edit: to actually address your question, we're talking here about getting a bricky to do a day or two's repointing, and the materials are virtually free. So that's a job that costs hundreds, not thousands, if it even needs doing. 

woody7777

Why does the heat from the sun crack bricks, when they are baked in a hot kiln and don't snap in half?

casper_gutman

woody7777 said:

Why does the heat from the sun crack bricks, when they are baked in a hot kiln and don't snap in half?

Because in the kiln each individual brick can expand to accommodate the expansion it undergoes when it's heated. In a wall, the surrounding structure restrains the ends of the bricks so when different parts try to move in different directions cracks can result.