ᐅ House extends above ground level – how much soil can be backfilled (with shallow basement)?

Created on: 15 Oct 2022 19:11
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Machu Picchu
Hello everyone,

we are now in the final phase of our house construction.

Because the sewage system on our property is not far below ground level and we did not install a sewage lift system, our basement was only excavated to a shallow depth.

The ceiling height of the basement rooms is 2.50m (8 feet 2 inches), as these areas are intended to be living spaces, unlike the neighboring houses, whose basement heights are lower.

As a result, our front door and the two patio doors are positioned much higher than those of the neighboring houses. In the next few days, soil will be filled up to the level of the terrace and front doors.

I do not want this to turn into a discussion about different construction methods; instead, I am looking for advice on how to best handle this somewhat unusual situation.

First, some photos:



Marked in red are the two patio doors. Soil will be filled up to just below these patio doors, except, of course, at light wells and shafts. The terrace will be paved around the corner, following the two indicated patio doors (because we wanted two sunny sides on the terrace for different times of the day). To the left of the single-leaf patio door (where the exterior plaster ends), a retaining wall will be built from the terrace level down to the ground.



This is a front view. On the left, the construction staircase leads up to the entrance door. The front door is at the same level as the two patio doors.



Here is the view from the back.



This is the view from the back toward the front door.



And here is another rear view including the neighboring houses.

As planned, as mentioned, soil will be filled up to the level of the house and terrace doors, and at this level the garden will be designed on the side of the large double patio door as well as behind the house, with steep slopes created just before the property boundary.

On the front door side, soil will also be filled up to front door level.

Toward the "front" (the side with the single patio door), the street level will be reached by terrace-like steps with 2-3 slope terraces supported by walls/granite.

Our concern now is: if we fill soil all around the house at door level on the side with the double patio door, at the back, and on the front door side, our garden height will be so high that, compared to the neighbors, our house will stand out significantly due to the very elevated ground level.

We are now considering ways to soften this.

One idea is to fill soil to door level only at the terrace wrapping the corner and directly at the front door, and to fill soil, for example, 50cm (20 inches) below door level everywhere else.

This way, the garden level would not be so dramatically higher than the neighbors’.

The problem with this is that we would partially expose the "basement" and areas without exterior plaster would become visible. We would likely need to hire a plasterer on our own to plaster additional areas and paint them with gray base paint. Time is tight because the soil will be delivered for filling within the next days/weeks. How long would such plastering take and what would it approximately cost?

Question to the forum: What do you think about this? Do you have other solutions? Or are our concerns unfounded?

Thank you very much in advance for any advice.
11ant16 Oct 2022 19:04
K a t j a schrieb:

In my opinion, fixing this mess will cost around 70,000 to 100,000 (USD) depending on the method used.

Exactly, which is several dozen times more than the claimed "savings."
Myrna_Loy schrieb:

Normally, you only dig one pit for the basement plus working space. You don’t excavate the entire site down to the basement slab. That’s almost a foolish mistake.
Myrna_Loy schrieb:

Unless the excavation for the basement was the builder’s idea to reduce the cost of the excavation pit.

Honestly, I wouldn’t be surprised if someone as impressively prone to hindsight errors as the original poster did just that. However, I wouldn’t describe it as only “almost” foolish.
Machu Picchu schrieb:

So you wouldn’t backfill up to 2 meters (around 6.5 feet) near the patio door?

Under no circumstances would I ever backfill or mound earth up to a height of a person—ever. (Unless I was the producer of a scripted construction fail show on Surreality TV.)
K a t j a schrieb:

You were either not advised or badly advised. He (the contractor) shares some of the blame and should contribute to the cost of fixing the problem.
Myrna_Loy schrieb:

I would have the general contractor’s (GC) advice and workmanship reviewed. The clients seem too inexperienced and naive to properly assess offers from a landscaping contractor. Otherwise, this might be the next disaster.

At best, this seems like poor advice rather than malpractice. A construction contract is not a financial or insurance product. If (and I understand this correctly) the terrace and landscaping are "client’s responsibility," I fear that legally the GC may have actually delivered a defect-free result. There is, as far as I know, no legal penalty for "neglecting to help due to naivety."
SaniererNRW123 schrieb:

1. Money for a lifting station was supposed to be saved
2. A GC with a low bid was sought
3. The GC’s proposal, essentially a “skyscraper” design, was approved exactly as-is by the client = the thread starter

2. A GC with a low bid (probably based on a finished owner’s design or similar) was sought;
1. One of the bidding GCs pointed out the drainage height problem;
3. The OP assumed: this guy is a fair and honest professional, the only one flagging the problem, and even generously abandoned the chance to charge us for an expensive lifting station > > > so we take him!
https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/
K a t j a16 Oct 2022 19:24
11ant schrieb:

"Failure to provide assistance due to naivety" is, to my knowledge, not punishable.
I don’t find the matter that clear. For a new build, a licensed professional responsible for the drawings must be involved, representing the design. The role of, for example, an architect is, in my opinion, a consulting service for which they are also liable. Quickly from the internet:

The Federal Court of Justice (BGH) clarified with its ruling of July 10, 2014 (Case No.: VII ZR 55/13) that the architect is already obligated during the preliminary assessment phase to discuss the client’s wishes with them and advise them accordingly on feasibility. If they fail or inadequately fulfill this duty, and the client invests in a building based on faulty advice that they originally did not want, the architect is liable for damages. The damages may include the costs of planning, preparation, and demolition.

In this case, the feasibility of the client’s wishes is already quite questionable, especially regarding the terrace, in my opinion. However, whether it can be proven that the consultation was inadequate—I wouldn’t want to bet on that. I would first think carefully about which solution is acceptable and then negotiate somewhat with the general contractor.

But I want to emphasize again that I am also just an amateur.
M
Machu Picchu
16 Oct 2022 19:30
11ant schrieb:



2. General contractor with an attractive offer (presumably for a finished self-design or similar) was sought;
1. one of the bidding general contractors pointed out the drainage height issue;
3. the original poster thought: he is a fair guy, the only honorable professional to point out this problem, and even generously forgoes the chance to rip us off with an expensive lifting station > > > let's take him!


Honestly, I don’t feel like responding to your cynical, condescending comment. Apparently, you find satisfaction in picking on our case and venting instead of contributing anything constructive.

Oh, and by the way: this was the exact opposite of a cheap house from a brochure. It was an architect-designed home with a custom plan by a renowned architect, who is also a general contractor, and who built my parents’ house 30 years ago as well as those of several school friends. All of these have been completely free of defects.
K a t j a16 Oct 2022 19:34
Machu Picchu schrieb:

An architect-designed house with a custom plan from a renowned architect, who also acted as the general contractor. He built my parents’ house 30 years ago, as well as those of several school friends. All of these have been completely free of defects.

What does he say about it? Have you raised the issue with him yet?
M
Myrna_Loy
16 Oct 2022 19:36
Then the architect should take a closer look at the exterior surroundings and present affordable proposals.
S
SaniererNRW123
16 Oct 2022 19:42
Machu Picchu schrieb:

Oh yes: It was the opposite of a cheap catalog house.
An architect-designed home with a custom plan from a reputable architect, who is also the general contractor, and who built my parents’ house 30 years ago as well as those of several school friends. All of these were completely free of defects.

So in the end, it was just a general contractor and not a “true” architect’s house. He planned it—together with you—according to your wishes and budget.
K a t j a schrieb:

I don’t think it’s that clear. For a new build, a certified professional authorized to submit plans must be involved and take responsibility for the design. The role of, for example, an architect is, in my view, a consulting role for which they also bear liability. Quickly found on the internet:

The architect did do that, if I understand the original poster correctly. You talked together about the drainage issue and agreed that the house should be elevated.

In the end, though, it doesn’t really matter who did what. The original poster approved everything and planned it together with the general contractor/architect.

So now it’s time to get the situation sorted out. But (unfortunately) only by the original poster. And that will either a) cost a lot of money and effort or b) require a complete adjustment of the landscaping.