How concerned would you be about cement render and damp?

[houseargh]

Just got the survey report back on the Victorian terrace that we're looking to buy. Lots of fairly standard things flagged that we're not too concerned about / the kind of small things we expect to have to be fixing over the next couple of years. But there are a couple that look like they could be biggies and I'd like to know WWYD.

Firstly, the house has been covered in impermeable cement render and the surveyor has flagged this can lead to damp. Moisture monitor indicates this happening in the front of the house (highest reading 566, not sure what type of device). They recommend either plugging cracks as a short term fix or getting the render removed.

Secondly, a lean to has been built over a sub-floor vent with no cross ventilation added so they've flagged this may have caused poor ventilation leading to dry rot under the floor, but no way to confirm without doing an inspection.

We've shared the report with a couple of family members who have owned houses this age. One said this is all just stuff surveyors say about these types of housed and there's no need to do anything unless/until we start getting damp showing on the internal walls.

The other said they'd be quite concerned about the render issue and it could be reasonable to try and negotiate a discount to cover the cost of removing it.

If it makes a difference - we are currently paying slightly over the lender's value/asking price which (for those who will say that is daft) is because we REALLY need to move and that's just how it is around here.

Is this something that would cause you to rethink your offer or just par for the course for old houses?

If at some point, you’re willing to take on the work and can financially do it then take the house but try to negotiate on price, if you love it so much. If you can’t do these repairs and any other damage you might find then walk away.

We've got an old house with cement in the grouting (I think that's the term) as the outside of the house is all stones
The damp is a constant battle

We were desperate to move too, so we panic bought I think, looking back. Now, we are in a house that needs a chuck load of work doing to it at a time when costs for tradespeople and materials are at an all time high. Just be really careful not to make the same mistake I did because I was so blinkered and focussed on moving! Good luck x

Victorian house built with soft red brick? Cement render will be a major problem eventually. Water gets behind the render, can't escape via evaporation and takes the easiest route, through the soft brick to inside. If the house has modern plaster internally, the water is trapped. ie damp. Fixed by removing the cement render, which will have damaged the surface of the brick. Would I buy? If cheap enough. Cheap.
We removed cement render from our house. Had to be done, the walls were saturated. House riddled with damp and mould inside. Previous owner had filled the cracks in the render with cement and silicone. It took months, we lost the external rear wall and the side wall in the process, they collapsed due to being so wet for so long. Replaced most of the bricks on the front wall. It was a pretty much a demolition site. The bricks so badly damaged it was re-rendered with specialist lime render. Massive bills. Massive! We completed most of the work ourselves too. Would I buy this house again? Now I would, but only if someone had salvaged the house correctly as we have. You paid for a professional opinion, you should at least seriously consider what the surveyor has said.

@Ohfgswhat this is really helpful, thanks. From our research we are definitely mindful to do the work - just waiting for quotes back. If the vendors refuse to reduce the price I'm not sure what we'll do. Can I ask what the state of yours was on the inside when you bought it? Were there any indications that it was in a bad way? On this one there are no obvious signs of damp on the inside, other than the reading the surveyor got - so there obviously is damp but I wonder if it would be naive to assume that means it's probably not catastrophic (paint on walls in good knick but didn't look brand new so it didn't appear to have been repainted just for selling though I guess you can't tell). Also, the surveyor obviously mentioned this (and the possibility that it might need rerendering with lime) but not that the walls might need replacing, which makes me think he saw no indications it had got to that point, though presumably without removing the render you can't tell for sure.

@houseargh would you be able to share the outcome here? Did you go ahead with the purchase and carry out render work?

@echobelly79 we went ahead with the purchase and haven't carried out the work yet because we can't afford it flat out, it'll be something to do in a few years when we can take out more money on the mortgage. Yes, that was possibly a risk - but we went ahead on the basis that there were no signs of damp internally despite the condition of the paintwork indicating that it had clearly not been done fresh for showing - so we decided to assume that it was liveable for the foreseeable. Also, many of the other houses on the road have the same render and people seem to be living with them fine. In a few years time our daughter will be out of nursery, we'll have more income to spare and be able to take out a bit more on the mortgage so we'll probably do it then. Possibly a more risk averse person wouldn't have done that but we absolutely love the house and neighbourhood, so no regrets so far

Oh, also - the quotes came back waaaaaay more than what the surveyor suggested. I think he had suggested 5k, quotes were in the range of 12-20k!!!! The vendor refused to reduce the price and I'm not entirely surprised tbh, given that most of the houses on the street have the same render, we decided to go for it anyway for reasons listed above

@houseargh sounds like a pragmatic approach - location and cost is key. as you say, you can always improve it later on. BTW, if you are going to remove the render later on, and the house is cold, you could consider removing it and then applying external wall insulation at the same time. I'm a big advocate for EWI for old cold houses so often mutter away about the benefits of EWI on these threads. it can still be done even for a terrace.

I pulled out of a houe sale as they had used cement instead of limestone. There were large areas of damp externally and internally.

Thanks for the update. It's an interesting topic - we are in situation where we bought a 1930s detached place about 3 yrs ago, that had the original rough cast render on it ( lime based, not cement) on both side walls. It was in a real state so we had it re-done couple of years ago and they used a cement based render. I've since been learning about the potential damp pitfalls of cement render on old, solid brick houses like these - on the one hand the Internet will make you feel like you're house is going to fall down and we've made the worst decision ever, but as you say a quick walk around the neighbourhood and you see so many similar houses with it on - our neighbours house has it on all 4 walls and been on for 30yrs apparently, cracks all over it but has no damp issues. I guess time will tell and there will be an element of luck to it - we're contemplating having it removed but that presents its own challenges financially and the risk to the brick work during the removal process. One piece of advice we had was to ensure you don't use gypsum/cement based plaster on the inside of the external walls and keep with the original lime based if you can. That way any water trapped in the wall has a route out, albeit at the expense of your paintwork, but prob better than being trapped in the walls for years.

I know this thread has moved on a bit, but will add my experience in case it helps anyone in the future. I’ll do a few posts to allow for relevant photos.

I purchased an old (around 250 years) timber-framed cottage. No signs of damp or mould inside and all internal timbers looked fine. The only thing flagged up was that the exterior had been painted in non-breathable paint. No mention of the fact that the cement render was a problem. I had no idea (yes, I know, naive) of what a problem could be.

Fast forward a few years, still no problems internally re damp etc. To this day I’ve never had any issue re condensation on the inside of windows, etc (a problem I see mentioned a fair bit on MN). Then Hurricane Katrina arrived. I’d already been out to see if I’d lost any fencing front or back. Was back inside and heard a thumping sound, nothing alarming, but checked out front and back windows - couldn’t see anything amiss. Ten minutes later, had neighbour across the lane knocking to check I was ok. This is what had happened at the side of my house. The cement was very thick - it had obviously been applied twice as you could see the two very different colours it had been painted. Am thankful no one had been stood there when it fell. There was no indication inside the house that anything had happened!

I won’t go into what a nightmare it was with regards to the extent of damage, yet alone the stress of getting it fixed. I’ll just explain the worst part of the damage to highlight how bad it can be when water gets into tiny cracks and the structure can’t breathe it out.

The large gap, above the brick, is where the sole plate should be. This is what the vertical beams slot into - the sole plate basically holds the whole timber frame in place. As you can see, 3/4 was pretty much gone. The other “side” of this was one of the visible beams in my living room and looked absolutely fine.

Had to have the side of the house propped up whilst works were carried out. A new sole plate was installed and a lot of remedial works was carried out on the rest of the frame.

Any “gaps” in the wall between the random bricks and the timber frame were stuff/laid with sheep’s wool insulation - this is breathable. Rather than redoing the whole wall with new lathes (very expensive), Savolit boards were used - these are breathable/fire-proof and they provide an extra layer of insulation.

This wall was then rendered with lime render. The guy who did it had not worked with rendering onto the boards before - he was really impressed with what a great surface it was to work on. The wall was then finished with traditional limewash.

Bloody hell Furries! Did your insurance company cover the repairs?

The following year, I went through the same process with the front of the house. I won’t bore with any more photos, but it was pretty much the same story.

The back of the house is slightly newer than the front half, but that also needs to be done at some point. Not sure when I’m going to have the funds to do it. I have low-level concern every time we have adverse weather!

Having said all this, I still love my house and can’t see me ever moving. But I wish I’d known more at the time regarding what different types of buildings “need” in order to be sound. As I would have walked away, or negotiated a lower price if I’d had any idea of what the potential outcome could be.

The one positive is that I got to see the inner workings of an old property. The timber-frame specialist showed me a few interesting points - he was able to identify a couple of large beams that were over 500 year’s old. Not many people get to examine the inner workings of their house like that.

Sadly not, they were able to wriggle out of it. Had to remortgage to get the works done - which was the rotten cherry on top of the manky cake!

Wow! that's a big job sorry that you had to go through that and thanks for sharing. Do you have an idea of how long the cement render had been ok there for?

Thank you. Am not sure how long it had been “ok” for, as it will have taken quite some time for the sole plate to decay like that. But the cement render had been on there for almost 50 years. Helpfully, there was a scrap of newspaper in the wall from the mid-60’s, annoyingly I’ve lost it so can’t check the exact date. They’d also shoved some of the empty cement bags in there for “insulation” 😂😢😂

Oh, we also found a mummified bird 😱