ᐅ Is it advisable to have the foundation slab inspected by a building surveyor?
Created on: 5 Jan 2023 12:28
B
bavariandream
Hello everyone,
In mid-December, the foundation slab for our single-family house was poured. The civil engineering company is a family-run business from the region with an excellent reputation. The preparations went very smoothly (they even started with the earthworks before we had signed the contract), and we didn’t have to worry about anything (they also handled various inquiries with the local authorities since they already knew each other).
On the day the foundation slab was poured, unfortunately, we were all very sick (middle ear infection with a fever just under 40°C (104°F)) and couldn’t visit the site (just getting to the bathroom was already a struggle). I went there the next day for a quick look. The slab was completely covered, which we expected because there had been heavy snowfall at the time and nighttime temperatures dropped to -12°C (10°F). The civil engineering company regularly works under such conditions; at our previous landlord’s site, they poured the slab on Christmas Eve despite heavy snow.
So far, so good. However, when we visited the site about a week later (we don’t live locally), some parts of the protective foil were missing. We suspect that children playing may have removed it because the wind alone shouldn’t have been able to do that—the foil was very well secured.
Now we don’t know exactly when this happened, so we’re unsure if the slab was already frost-resistant at that time, and we’re wondering if this might have had any negative effects. Visually everything looks fine and, for example, I haven’t noticed any cracks. The slab will be inspected in spring by our construction manager, but I assume they will mainly check if all measurements are correct.
Therefore, I wanted to ask here if you would recommend having the slab inspected by an independent expert. I’ve heard that organizations like TÜV Süd offer such services. Or is that money wasted because they would basically just measure again and check for cracks (as I said, I couldn’t see any; everything looked fine to me, but I am a complete layperson)?
Thank you very much in advance for your help!
In mid-December, the foundation slab for our single-family house was poured. The civil engineering company is a family-run business from the region with an excellent reputation. The preparations went very smoothly (they even started with the earthworks before we had signed the contract), and we didn’t have to worry about anything (they also handled various inquiries with the local authorities since they already knew each other).
On the day the foundation slab was poured, unfortunately, we were all very sick (middle ear infection with a fever just under 40°C (104°F)) and couldn’t visit the site (just getting to the bathroom was already a struggle). I went there the next day for a quick look. The slab was completely covered, which we expected because there had been heavy snowfall at the time and nighttime temperatures dropped to -12°C (10°F). The civil engineering company regularly works under such conditions; at our previous landlord’s site, they poured the slab on Christmas Eve despite heavy snow.
So far, so good. However, when we visited the site about a week later (we don’t live locally), some parts of the protective foil were missing. We suspect that children playing may have removed it because the wind alone shouldn’t have been able to do that—the foil was very well secured.
Now we don’t know exactly when this happened, so we’re unsure if the slab was already frost-resistant at that time, and we’re wondering if this might have had any negative effects. Visually everything looks fine and, for example, I haven’t noticed any cracks. The slab will be inspected in spring by our construction manager, but I assume they will mainly check if all measurements are correct.
Therefore, I wanted to ask here if you would recommend having the slab inspected by an independent expert. I’ve heard that organizations like TÜV Süd offer such services. Or is that money wasted because they would basically just measure again and check for cracks (as I said, I couldn’t see any; everything looked fine to me, but I am a complete layperson)?
Thank you very much in advance for your help!
B
bavariandream5 Jan 2023 14:10xMisterDx schrieb:
Since the site manager inspects your work before the house is erected, it’s possible that he will point out defects if there are any.
That doesn’t bother him at all; on the contrary, if he builds his house on a faulty foundation slab and problems arise later, he’s the one responsible... after all, he is the expert and should have caught it.
If I remember correctly, there are also certain safety factors in structural engineering. No structural engineer designs a foundation to work only just barely, assuming the builder follows everything exactly. They’re not exactly naive.
The same goes for the foundation grounding system. It’s not such a big deal in a TN-C-S system but could be a problem in a TT system. Thank you, that’s a good point. Maybe we’ll speak with our site manager again beforehand and ask what exactly he checks during his inspection. I will also ask the civil engineering company how critical the membrane would be if it was indeed removed too early (everyone here—including me—is still on vacation at the moment).
W
WilderSueden5 Jan 2023 14:47bavariandream schrieb:
I’m only concerned about whether frost damage could have occurred due to the possibly premature removal of the foil.This mainly depends on when exactly the foil was removed. The first few days are critical; after 2-3 days, the foundation slab can freeze through without sustaining damage.X
xMisterDx5 Jan 2023 16:01bavariandream schrieb:
(...)
I appreciate any advice, but tips like “it would have been better to do this beforehand” don’t help me at all. As I said, the groundwork company regularly works in snow and cold temperatures, and we’ve only heard positive feedback from friends and acquaintances who had their slab poured under similar conditions. So, I’m not questioning whether the groundwork company did everything correctly. My concern is whether removing the plastic sheeting too early might have caused frost damage and if an expert could still detect that damage afterwards.Well, if anyone can, it’s an expert. If you’re unsure, you should definitely get one involved.
I understand that advice like that isn’t useful to you. However, this is a forum where many people read and might avoid making the same mistake thanks to such tips. As for your acquaintances… did they have an expert inspect the foundation before and the slab after the work was done? If not, how do they know the work was properly executed?
I would always be very cautious about recommendations like that. Just because a house still stands after five years doesn’t necessarily mean every step was done 100% correctly.
They often do this, have a good reputation, and even poured the slab for your landlord in the snow.
To be honest, ask your colleagues about their holiday what they think about it.
If the answer makes sense... sleep well.
If not: get an expert appraisal.
Without at least some trust, you won’t be able to rest if it continues, just my opinion.
To be honest, ask your colleagues about their holiday what they think about it.
If the answer makes sense... sleep well.
If not: get an expert appraisal.
Without at least some trust, you won’t be able to rest if it continues, just my opinion.
B
bavariandream5 Jan 2023 20:27xMisterDx schrieb:
Well, if anyone can do it, it’s an expert. If you’re unsure, get one involved.
It’s clear that tips like these don’t help you directly. However, this is a forum, and many people read it who might avoid such mistakes thanks to advice like this.
About your acquaintances… did they have an expert inspect the foundation beforehand and the slab afterward? If not, how do they know that the work was done properly?
I would always be very cautious with recommendations like that. Just because the house is still standing in the same spot five years later doesn’t mean all the work was done 100% correctly. You’re definitely right, but in this thread I was specifically concerned about possible frost damage caused by the removed covering. That’s something an expert couldn’t have prevented in advance.
Our previous landlord had the slab poured in winter 2015, and since we are good friends with his daughter, who lives in the house, we at least know that there were never any problems there. Their home builder even said they rarely see such a nicely poured slab. Our prefabricated house supplier also said that although the civil engineering company has been around for over 30 years, they have never heard or seen anything negative about them. So I really have full confidence that they did a proper job.
But just to clarify, obviously someone partially removed the covering from our slab, because when we visited again a week later, it was missing in some areas. We don’t know exactly when this happened. We only know that everything was fine the day after the pour. We don’t know if someone removed the covering on day 2 or day 6, because we weren’t on site in between (it’s a new development area and there are always many onlookers).
The question we have is: how can potential frost damage be identified afterward if the covering was removed as early as day 2, when the temperature at night was -10°C (14°F)? Besides cracks, are there other signs to watch for? And would an expert possibly be able to see more than a site manager?
M
Marvinius5 Jan 2023 21:03bavariandream schrieb:
You’re right, of course, but in this thread I was specifically concerned about potential frost damage caused by the removed membrane. That’s not something an inspector could have prevented beforehand.
With our previous landlord, the concrete slab was poured in winter 2015, and since we are good friends with his daughter who lives in the house, we know there were never any problems. Their construction company even said they rarely saw such a well-poured slab. Our prefabricated house supplier also said that although the civil engineering company has been around for more than 30 years, they have never heard or seen anything negative about them. So I truly have full confidence that they did the job properly.
But to clarify again, obviously someone partially removed the cover from our slab, because when we returned a week later, it was missing in some places. We don’t know exactly when this happened; we only know that everything was fine the day after. Whether someone removed the cover on day 2 or day 6, we don’t know, as we weren’t on site during that time (it’s a new development area and there are always many onlookers).
The question for us is how to identify possible frost damage afterwards if the membrane was removed as early as day 2, when the temperature dropped to -10°C (14°F) overnight. Apart from cracks, is there anything else to look out for? And would an inspector possibly notice more than a site manager? You’re worrying way too much. You should try to take it easier. Your construction phase will get a lot more stressful…..
Similar topics