ᐅ Massive water damage caused by a leaking underfloor heating system

Hello dear forum,

We are currently having our single-family house built by a developer.

Three days ago, I visited the construction site and was shocked to find that drying machines are set up throughout the entire ground floor, and in every room the screed has been drilled (one or two openings per room) with hoses inserted for drying purposes.
There are water stains on all the walls (gypsum plaster), rising about 15–20 cm (6–8 inches) from the floor.
Our house has no basement and is built on a slab foundation.
The floor structure is as follows:
Slab foundation, waterproof membrane, insulation (PS rigid foam, thermal conductivity 0.035 W/mK), cement screed including underfloor heating.
No floor covering has been installed yet.

Our site manager has not informed us about this serious defect until today.
After I inquired by email yesterday, I have still not received any response.

Our handover date (end of June) and therefore the planned move-in date are now pointless.

My big request is: How should I proceed, and what should I keep in mind to avoid unpleasant surprises later on regarding mold and other consequential damage?

Questions:
Should I stop all payments to the developer now (outstanding invoices amount to about 22,000 euros)?
Can I charge the developer for the electricity consumption of the drying machines (about 100 kilowatt-hours per day), as meter readings have been recorded?
We have already terminated our rental agreement and now have to try to get an extension from our landlord. If the repair of the building defects takes a long time, for example due to dismantling work necessary to remove moisture from the floor—especially the moisture under the insulation—can I claim the additional rental costs from the developer?
The construction contract states that in the event of delay, a daily penalty of 50 euros is payable from Monday to Friday, with a maximum claim of 5% of the contract sum. Does this apply also in case of delays caused by legal disputes?

Any guidance on how to proceed in this case would be greatly appreciated. We have a young daughter, 13 months old, and want to avoid any health issues related to mold or other construction defects at all costs.

Thank you very much to everyone who can offer helpful advice.

Bernd

Well, it’s an unfortunate situation, but it can happen. You don’t need to worry about mold because there are drying machines in place. The costs for these should be covered by the responsible party’s insurance.
The drying machines will take care of everything. What this means for you otherwise, or how much money you can or should withhold, is something only a lawyer can advise you on.

Hello Bernd,

posterino schrieb:
...Our site manager has not even informed us about this serious defect until today.

First of all, the term "serious defect" is not correct; since the house has not been handed over yet, it is not a defect in the legal sense. However, it is certainly a mistake on the site manager’s part not to inform you about the measure and the associated "possible" delay in construction progress.

posterino schrieb:
Our handover (end of June) and therefore the move-in date are no longer valid

Not necessarily.

posterino schrieb:
My big request now, how should I proceed or what should I keep in mind to avoid unpleasant surprises later regarding mold and other consequential damage.

Definitely try to stay calm.

posterino schrieb:
Should I stop the payments to the developer from now on (outstanding claims approx. 22,000 Euros)

On what grounds? If the pending progress payments relate to properly completed trades, you cannot arbitrarily withhold payments just because other areas of the house are not yet to your satisfaction. What you might consider, however, is reducing the payment for the “screed” phase by a certain percentage point “X”; for this, the applicable regulations (depending on whether your contract follows the VOB or the Construction Code) or a specialized construction law attorney can provide advice.

posterino schrieb:
Can I charge the developer for the electricity (approx. 100 kilowatt-hours/day) used for the construction dryer – meter readings have been recorded

What does your contract say? I am fairly certain you will find a clause stating that any building drying costs are your responsibility.

posterino schrieb:
We have already terminated our rental apartment and now have to try to get an extension from the landlord. If the remediation of the construction defects takes a long time, for example due to dismantling because otherwise the moisture cannot be removed from the floor, especially the moisture under the insulation, can I claim the additional rental costs from the developer? The building contract only states that in case of delay, 50 Euro per day from Monday to Friday is paid and the maximum claim is 5% of the construction sum. Does this also apply in case of delays caused by legal disputes?

How is the construction period contractually agreed upon and by how long has it been exceeded up to now?

Kind regards

Hello construction expert,

many thanks in advance.
Here are a few additions to the post...

construction expert schrieb:
Hello Bernd,

First of all, the term "serious defect" is incorrect; the house has not been handed over yet, so it is not a defect. What certainly is a mistake on the part of the site manager is not informing you about the measure and the resulting "possible" delay in construction progress.

Not necessarily.

According to an independent master craftsman and expert, the drying takes at least 4-6 weeks...

Certainly things will calm down

I had a conversation yesterday with an expert who said that the residual moisture below the rigid foam insulation cannot be removed by the construction dryer and that mold will develop over time. After this information, it is not so easy for me to stay calm.

On what grounds? If the open progress payments properly relate to completed work, you cannot arbitrarily withhold payments just because the house does not yet meet your expectations in other areas. What you might consider is reducing the "screed" payment by a certain percentage; the applicable law (depending on whether the contract is based on the German Construction Contract Procedures (VOB) or the Civil Code) or a knowledgeable attorney specialized in construction law can provide advice here.

The contract is regulated under the Civil Code, what payment reduction does the law allow in this case?

What does your contract say? I am fairly certain you will find a clause stating that any necessary drying of the house is your responsibility.

The contract states:
"The construction power and water connection must be available on the property. The consumption costs for the construction power and water used by us are included in the fixed price and will be charged against the 'acceptance' installment according to § 2, No. 4 upon proof. Consumption costs for heating and warming the house are at the expense of the client."

What is the agreed construction period and how much has it been exceeded so far?

The construction period is limited to 6 months, the site manager promised us that the construction would be completed after 4 months, which would be in about 14 days.
And yes, I myself know that this statement is not binding since the contract says otherwise.
I have already come to terms with that.

For us, it is simply important to know how to proceed.
Just trusting the builder when they say there is no residual moisture anywhere in the floor structure is not very reassuring for us, especially since we have become quite skeptical towards the builder due to other issues as well.
Should we definitely have an expert inspect after the drying, or is it generally true that after using a construction dryer the matter is usually resolved?

Thanks and best regards
Bernd

Kind regards

Hello Bernd,

posterino schrieb:
According to an independent craftsman and expert, the drying process takes at least 4-6 weeks...

Did he visit your construction site or just answer a question? There are different types of screed with varying drying times...

posterino schrieb:
I had a conversation yesterday with an expert who said that the residual moisture beneath the rigid foam insulation cannot be eliminated by the construction dryer and that mold will develop over time. After hearing this, it’s not easy for me to stay calm...

Understandable, but again the question: was the expert on your construction site and inspected the building, or did he merely respond to one of your questions?

posterino schrieb:
The contract is regulated under the Building Code; what kind of payment reduction does the law provide here? ...

§ 634
Rights of the Client in case of Defects
If the work is defective, the client may, provided the requirements of the following regulations are met and unless otherwise stipulated,

	1.	demand subsequent performance according to § 635,
	2.	carry out defect rectification themselves and claim reimbursement of necessary expenses under § 637,
	3.	withdraw from the contract according to §§ 636, 323, and 326 section 5 or reduce the payment according to § 638 and
	4.	claim damages according to §§ 636, 280, 281, 283, and 311a or compensation for wasted expenditure under § 284.

posterino schrieb:
The contract states:
"... consumption costs for heating and warming the house are the responsibility of the client." ...

That was what I expected.

posterino schrieb:
The construction period is limited to 6 months; the site manager promised us the building would be finished after 4 months, which is in about 14 days. And yes, I know that statement has no legal significance since the contract states otherwise. I have already accepted that...

Wow—house construction used to take a good year; and for good reasons! Nowadays, 6 months (starting from the foundation slab) is already very fast, considering all the trades involved, drying times, and the minor mistakes that inevitably occur.

posterino schrieb:
For us, it’s simply important to know how to proceed. Just trusting the builder if he says there is no residual moisture in the entire floor assembly is not very reassuring, especially as we have become quite skeptical towards the builder for various reasons by now...

At least for your own peace of mind, consider hiring an independent expert to inspect the building?

posterino schrieb:
Should we definitely involve an expert after the drying process, or is it generally the case that once a construction dryer is used, the issue is resolved?

No, you should bring in an expert at this stage—if only to confirm that you have nothing to worry about. You seem to be a bit unsettled; that alone should be reason enough.

And yes, wherever we have used a construction dryer, there were no later problems. BUT this can’t be generalized or considered a blanket statement!

Best regards