House buying worries - 1930s semi

[larches]

Hi all. Having spent what feels like an eternity house-hunting, we have found a 1930s semi that meets most of our needs and we're considering putting in an offer. We have previously owned 'new build' so are trying to suss out what the risks are in buying an older property so we can have realistic expectations.

We came away from our first viewing with the strong impression that the current owner has looked after the house well and invested in keeping it in good condition, certainly compared to others we've viewed in the same area. We have just had a second viewing and that impression hasn't changed a lot, but we did notice a few things we'd missed the first time around, including what could be signs of damp (either past or current), and a few cracks in walls.

I'm attaching some photos and wondered if anyone with experience would mind casting their eye over them - I'm guessing this sort of thing is not uncommon.

Photo 1 shows an area of wall in the front room, in the corner beneath the bay window (SE-facing) closest to the wall adjoining next door. You'll see the speckling which looks like it could be (or have been) mould, although there is no smell of mould and it had a slightly odd appearance which made me wonder if it had been painted over at some point.

Photo 2 is in the dining room at the back (NW-facing) on the side of what is presumably the original chimney breast (just plain wall now with no fireplace) - you can see where it has bubbled up next to the power socket, and there has been some repair work down that corner including the skirting. The floor also looks a bit discoloured there, and it's hard to be sure but I wondered if that left screw in the socket is showing a bit of rust. Can't say I like the look of this, but again, I'm not sure if this is just the remnants of a past problem. Didn't seem obviously damp, but then the weather's been reasonably dry.

As it happens, we spoke to the adjoining neighbour and she mentioned having a damp problem in the hall cupboard, which she hasn't had looked at yet. So we asked the vendor (via the estate agents) if there has been any history of damp in this house and she said yes, in the hall cupboard (surprise), and that a new damp proof course was done last year to resolve it. I don't know if that DPC will also have addressed any damp issues in other parts of the house. She did say the roof had been completely replaced around 15 years ago, but that's probably when the loft conversion was done. I'm still trying to figure out why the hall cupboards are the issue in these houses. Both have been extended with (what is now) an integral garage on the side with rooms above, and the hall cupboard is under the stairs and backs onto the garage (presumably originally the outer wall). I'll attach the floorplan too.

Photo 3 shows cracking around the dining room windowsill, normal enough I think. No obvious damp in the corners of the windows (unlike our previous new build!). Photos 4 & 5 show cracks in the kitchen wall which is in an extension built over 10 years ago - maybe just normal settlement cracks? Photos 6 & 7 - cracks on bedroom walls. Not sure if they're of any concern. Photo 8 - cracks around the underside of the staircase (two flights due to the loft conversion).

So - any thoughts on that lot - or general things to watch out for with this sort of house? Currently it's the damp that bothers me most as it's not something we've had to deal with before and I wonder if it could be difficult and expensive to resolve. Buying the house would cost more than we had originally intended to spend, so although we're trying to keep some funds in reserve for maintenance, they will be limited and we really need to avoid a 'money pit' situation. I wonder about lead pipes too, and then there's the wiring - the current owner has been there for donkey's years and says she doesn't know if it's ever been rewired - probably my next biggest worry as even aside from the major cost, we may not have time to get that done before we need to move (but I don't know if it's safe not to bother!).

Obviously we would get a full building survey done, but I'd rather weigh this up before we get that far - it's not just the cost if we ended up pulling out but also the lost time would be a problem as we need to get moving ASAP. We could just go for the 1990s house on our shortlist (similar cost) which is maybe less risky but that feels like a bit of a cop-out! Such a big decision, so any advice gratefully received.

 

[malcolm]

A 1930s house will likely have been built with solid brick walls and lime mortar. It's a very simple system - the lime lets water evaporate away from the walls and keeps the house dry. Bad things that can happen are cement pointing, cement renders or modern paints on the outside walls as any of those will trap water in the walls.

Down at floor level you want the exterior ground level maybe 6 inches lower than interior floor level so water can evaporate away from the walls before it can get inside. If you have wooden floors with joists then you want a good few air bricks underfloor allowing cross flow of air and make sure they are not blocked. It's good to have somewhere for the drain pipes to send water other than into the bottom of the walls. If you can get all the above sorted then you shouldn't have any damp problems.

Inside it's a nice not to have modern emulsion paints as they aren't breathable but pretty well every house will have emulsion paints. Little cracks everywhere don't tend to be a problem. The house will move around a little making the cracks appear and you fix them with filler.

The damp proofing already done in modern times will be either useless or will have caused more harm than good. Don't put your hopes in that.

 

[paulc]

A 1930s house will likely have been built with solid brick walls and lime mortar. It's a very simple system - the lime lets water evaporate away from the walls and keeps the house dry. Bad things that can happen are cement pointing, cement renders or modern paints on the outside walls as any of those will trap water in the walls.

1930s was on the cusp of cavity wall construction. In large parts of the country, it isn't unusual to find the lower half built with cavity walls, and the upper half, solid brick. Often, the upper half is rendered. One clue is the depth of the window reveals. 6" for solid brick, and 8" with cavity.
I spy uPVC windows - If the walls are cavity construction, you need to ask if lintels were put in to support the outer leaf of brickwork. Often, the original wooden frames would have been providing structural support. Replace the windows with uPVC without inserting a lintel over the window/door opening, and the brickwork will start to sag leading to distortion in the frames and cracks appearing above on the outside.

 

[larches]

Thanks both, that's all helpful (and shows me how much I have to learn).

1930s was on the cusp of cavity wall construction. In large parts of the country, it isn't unusual to find the lower half built with cavity walls, and the upper half, solid brick. Often, the upper half is rendered. One clue is the depth of the window reveals. 6" for solid brick, and 8" with cavity.
I spy uPVC windows - If the walls are cavity construction, you need to ask if lintels were put in to support the outer leaf of brickwork. Often, the original wooden frames would have been providing structural support. Replace the windows with uPVC without inserting a lintel over the window/door opening, and the brickwork will start to sag leading to distortion in the frames and cracks appearing above on the outside.

Good tip! Thankfully at the front there are sturdy-looking stone lintels in this case - quite a prominent feature in these particular houses on the street. However, the back is very different - curved rather than angular bay windows, and the section between upper and lower is fully rendered, so can't see what the construction is like underneath.

Regarding cavity wall, the EPC report (for what it's worth) says:
Wall: Cavity wall, as built, no insulation (assumed) Poor
Wall: Cavity wall, as built, insulated (assumed) Good

As with most EPCs, it's maddeningly vague - not only does it say 'assumed', but it also gives no indication as to which wall each line refers to (though maybe it's obvious to someone more clued up than I am!). The first recommendation to improve energy performance is to add cavity wall insulation, so the surveyor obviously thought it should be possible (makes me wonder why it hasn't been done already). Given what @malcolm said above though, I do wonder if this is one of those modern approaches to be wary of when dealing with a house from a previous era.

 

[paulc]

The EPC needs to be taken with a pinch of salt. One property not far from me is listed as being timber frame construction Built in the 1920s, it is cavity on the lower half solid brick on the upper half and the only timber framing is internal stud walls.

If you post a link to the property listing, we can take a stab at the likely construction based on visual clues.