Remediate an Oil Tank Room – Remove Heating Oil Odor and Residues

1. Why Does an Old Tank Room Smell of Heating Oil?

An intense heating oil odor does not necessarily indicate a current leak.

Over many years, heating oil components may enter surrounding building materials through minor leaks, spills during filling, pipework or prolonged exposure.

Particularly absorbent materials include:

• plaster
• brick masonry
• concrete
• screed
• joints and cracks
• untreated mineral floor surfaces

After the tank has been removed, the contamination often becomes more clearly visible or noticeable by odor because previously concealed wall and floor surfaces are now accessible.

2. Fully Clear and Inspect the Tank Room

Before cleaning begins, the room should be made as fully accessible as possible.

After removal of the tank installation, walls, floors and, where applicable, adjoining building components should be inspected for visible discoloration, oil residues and odor contamination.

Particular attention should be paid to:

• the former tank installation area
• surfaces underneath and behind the tanks
• wall areas directly behind the tank installation
• pipe and service penetrations
• joints and cracks
• lower wall areas
• areas around former connections

If free heating oil or oil-containing liquid is still present on the floor, first absorb it using Bestabsorb Universal Oil Binder .

3. Remove Old Tank Room Coatings and Barrier Coatings

Many older tank rooms have oil-resistant tank room coatings, barrier coatings or other water-repellent finishes.

These can prevent Omnixol FX100 from penetrating into the contaminated building material underneath.

Such coatings must therefore be removed from the areas to be treated if they form a barrier between the cleaning solution and the mineral substrate.

Emulsion paints or coatings applied at a later date may also interfere with deep cleaning.

For effective treatment, Omnixol FX100 must have direct access to the contaminated, absorbent substrate.

4. Assess Heavily Contaminated Plaster

In older tank rooms, heating oil may have penetrated deep into the existing plaster.

If the plaster is heavily contaminated, we recommend removing it before treatment. This provides direct access to the underlying masonry and allows Omnixol FX100 to penetrate more effectively into the actual building material.

In cases of lighter contamination, existing plaster can be treated provided that it is sufficiently absorbent and free from barrier coatings.

If a wall has been replastered several times over the years, targeted drill holes extending to the original plaster or the actually contaminated masonry may be useful.

5. Dry and Warm the Tank Room Before Cleaning

The substrate to be treated should be as dry as possible.

Before applying Omnixol FX100, we recommend heating the room to at least approximately 20 °C.

A relative humidity of ideally below 50 % supports the drying process.

Heating may temporarily make the heating oil odor more noticeable. This can occur because volatile components stored within the building material are released more strongly at higher temperatures and enter the indoor air.

Therefore, ensure adequate air circulation and, in cases of strong odor contamination, use suitable respiratory protection if necessary.

Open flames, smoking and other ignition sources must be avoided in oil-contaminated rooms.

6. Deep-Clean the Tank Room with Omnixol FX100

For treating contaminated mineral surfaces, use Omnixol FX100 Concentrate .

For older tank rooms with significant or deep-seated contamination, we generally recommend a mixing ratio of approximately 1:10.

For normal or lighter contamination, Omnixol FX100 can be diluted with water up to approximately 1:20.

Warm water is recommended where possible.

Apply Omnixol FX100 generously to the contaminated surfaces using a suitable pressure sprayer, masonry brush or paint brush.

Walls and floors must be sufficiently saturated and not merely lightly wetted at the surface.

The aim is to allow the cleaning solution to penetrate the contaminated pores and capillaries of the mineral building material.

7. Use Targeted Drilling for Deeply Contaminated Masonry

If the heating oil contamination is deeply embedded in the masonry, Omnixol FX100 can additionally be introduced into the building material through targeted drill holes.

The holes are arranged in an even pattern and drilled into the actually contaminated brick or concrete core.

This allows the cleaning solution to reach areas that would otherwise be difficult to access through surface treatment alone.

On walls that have been replastered several times, the holes should reach at least as far as the original plaster or the contaminated masonry.

Important: Before drilling, possible pipes, reinforcement, waterproofing and the structural composition of the building component must be taken into account. For load-bearing components or structures of unknown construction, professional assessment should first determine where drilling can be carried out safely.

8. Allow Omnixol FX100 to Act for Approximately 24 Hours

After application, Omnixol FX100 should be allowed to act for approximately 24 hours.

Omnixol FX100 disperses and emulsifies oil-containing contamination and supports its mobilization from the porous substrate.

During this process, milky-white or oily residues may become visible on the surface.

These should then be thoroughly wiped away or removed using a suitable wet vacuum.

9. Check the Treatment and Repeat if Necessary

In many cases, one thorough treatment is sufficient.

However, tank rooms that have been used for decades or are heavily contaminated may require a second application with Omnixol FX100.

After each treatment, residues that emerge are removed and the treated surfaces are allowed to dry again.

As a general guideline, 1 liter of Omnixol FX100 Concentrate is sufficient for approximately 10 m² of surface for a single treatment.

When calculating the required quantity, the tank room floor area alone should not be used. Depending on the extent of the damage, walls, lower wall areas and other contaminated building components must also be included.

10. Does the Ceiling in the Tank Room Need to Be Treated?

The ceiling does not automatically require deep cleaning in every tank room.

Treatment is advisable where there is visible contamination or a relevant odor problem.

After decades of use, odor-causing substances and oil-containing aerosols may also settle on higher surfaces.

Whether the ceiling requires deep cleaning or whether subsequent odor neutralization is sufficient should therefore be decided according to the actual condition of the affected area.

11. Allow the Tank Room to Dry Completely

After the FX100 treatment has been completed, all treated surfaces must be allowed to dry completely.

Only once the surfaces are dry can it be reliably assessed whether significant odor contamination is still being released from masonry, plaster, screed or concrete.

Ensure adequate air circulation during the drying phase.

New paint, plaster, coatings or sealers should only be applied once the treated surfaces are completely dry and free from odor.

12. Neutralize Remaining Odors with Omnixol BX

After the actual deep-cleaning process, odor-causing substances may still remain in the room or on surfaces that are not deeply contaminated.

After completion of the FX100 treatment and complete drying, use Omnixol BX Odor Neutralizer .

Omnixol BX is applied to odor-contaminated areas and is used as a follow-up treatment for remaining odor contamination.

The correct sequence is:

1. Deep-clean contaminated mineral building materials with Omnixol FX100.
2. Completely remove residues that have emerged.
3. Allow the treated surfaces to dry completely.
4. Neutralize remaining odor contamination with Omnixol BX.

Omnixol BX does not replace deep cleaning of the actual heating oil contamination.

13. Apply a Final Sealer to the Tank Room

Only once cleaning has been successfully completed, the substrate is completely dry and the tank room is free from odor should Omnixol Wall & Floor Sealer be applied to suitable mineral surfaces.

It forms an additional protective layer, helps consolidate suitable mineral surfaces and acts as an additional odor-inhibiting barrier.

The sealer must not be used merely to trap existing heating oil contamination within the substrate.

Therefore, the correct sequence is:

Clean → remove residues → allow to dry completely → confirm that the surface is free from odor → apply Omnixol Wall & Floor Sealer.

What if the Tank Room Still Smells After Months of Ventilation?

Ventilation removes odor-causing substances from the indoor air, but it does not eliminate heating oil contamination stored deep within the building material.

If a tank room continues to smell of heating oil after weeks or months, the plaster, masonry, concrete or screed should therefore be checked for contamination.

In this case, the affected building material itself must be treated.

Does the Entire Tank Room Need to Be Replastered?

Not necessarily. The decisive factor is how severely and how deeply the heating oil contamination has penetrated into the existing plaster.

Heavily contaminated plaster should be removed. If the plaster is only lightly contaminated, sufficiently absorbent and free from barrier coatings, treatment with Omnixol FX100 may be possible.

In very old and heavily contaminated tank rooms, however, removing the plaster is often the most effective way to gain direct access to the contaminated masonry.

Can a Former Tank Room Be Used for Another Purpose Afterwards?

In principle, a former tank room can be put to a new use after successful remediation, provided that the structural requirements for the intended use are met.

Before further conversion work, however:

• the heating oil contamination should have been sufficiently removed,
• all treated surfaces should be completely dry,
• no significant odor contamination should remain,
• and any necessary structural work should be completed.

Only then should new plaster, floor constructions, coatings or other interior finishing work be carried out.

When Should a Professional Remediation Company Be Involved?

Professional remediation is particularly advisable in cases involving:

• large areas of contamination in tank rooms
• heavily saturated masonry
• visible oil deposits in several building components
• unknown depth or spread of the contamination
• damage to screed, insulation or concealed building components
• very strong odor despite prolonged ventilation
• larger leaks
• flood damage involving heating oil

In these cases, it should first be determined which building components can be retained and which may need to be removed or require more extensive remediation.

The Omnixol Approach to Oil Tank Room Remediation

For systematic remediation, we recommend the following sequence:

1. Absorb free heating oil – using Bestabsorb Universal Oil Binder
2. Remove barrier paints and coatings that interfere with treatment
3. Remove heavily contaminated plaster if necessary
4. Allow the tank room to dry completely and heat it to at least approximately 20 °C where possible
5. Deep-clean contaminated masonry, concrete and screed – using Omnixol FX100 Concentrate
6. For deep-seated contamination, use targeted drill holes if necessary
7. Allow Omnixol FX100 to act for approximately 24 hours and remove residues that have emerged
8. Repeat the treatment if necessary
9. Allow treated surfaces to dry completely and confirm that they are free from odor
10. Neutralize remaining odor contamination – using Omnixol BX Odor Neutralizer
11. Finally protect suitable mineral surfaces – using Omnixol Wall & Floor Sealer