Mould and mildew in interior spaces - effective prevention, sustainable renovation

KEIM Mycal®

PREMIUM is our Standard.

A88DRP

KEIM

Myca

l-Top

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Growth conditions for mould

Micro-organisms such as fungus and bacteria are a natural part of our active environment and are usually tolerated by people without noticeable reactions. However, if the concentration of mould exceeds a certain quantity, it can lead to serious health problems.

Moisture, nutrient supply, tempera-ture and pH value are factors that are crucial in determining the growth of mould.

Mould fungi grow already at a rela-tive humidity of 70% and even on materials or surfaces that are not visib-ly wet. All that is required is suitable surface dampness. Although the most important factor is moisture, the conditions with regard to temperature and nutrient supply must be met at

the same time over a specific period in order to allow mould to grow. Mould fungi can only grow within a certain temperature range, which is, however, relatively wide from approx. 0 to 55°C.

With regard to nutrient supply, mould is able to use a variety of materials as a nutritional basis. These include primarily organic substances such as cellulose, wood, wallpaper, paste or water-based substances.

Finally, pH value also has a dramatic effect on the risk of an infestation. The optimum growth range is between 5 and 7. But most mould fungi already grow when the range is between 3 and 9. In an alkaline environment, however, fungi do not generally grow.

Mould and mildew in interior spaces

Relative humidity in %

Nutrients

Tem

per

atu

re in

°C

pH

valu

e

Risk areas for the growth of mould fungi

The growth of mould fungi is most distinctive in

these areas.

40

70

60

50

40

30

20

10

0

11

12

10

9

8

7

6

5

4

45 50 55 60 65 70 75 80 85 90 95 100

Professional renovation requires appropriate systems

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A prerequisite for the sustainable renovation of surfaces damaged by mould is elimination of the causes of the infestation. This is the only way to prevent a new infestation. Simply combating the symptoms usually only represents a temporary solution.

Combating the causes primarily calls for• avoidanceofmoisture and damp building components,• guaranteeingappropriate heating and ventilation and• theeliminationofbuildingdefects and damage caused by damp.

Moreover, the surfaces infested with mould must then naturally also be appropriately and professionally restored. It is best to refrain from using biocides indoors since these products may be assumed to be more damaging to health than the contamination caused by the microbial infestation.

Professional renovation and prevention

The following generally applies with regard to the renovation of surfaces damaged by mould: Infested surfaces or building components must be replaced and not treated.

The sustainable renovation of surfaces damaged by mould always requires the combating of the respective causes and removing the damage. Appropriate action to repair the respective surfaces must be determined in individual cases depending on the extent of the damage and its risk potential.

The Mycal - mould renovation system from KEIM consists of various indivi-dual products which offer individually adapted renovation options in various combinations.

Assessment criteria Low risk Medium risk High risk

Size of the visually infected area

Depth of the infection

Room usage

Risk of release of spores during the sanitation

Health condition of the user

0.5 m2

superficial

hardly occupied room

easy demounting of installations with no expected development of dust

good to very good

0.5 – 3 m2

< 0.5 cm

living and working quarters

avoidance of flying spores possible

average

> 3 m2

> 0.5 cm

hospital, kindergarten, seni-or citizen’s home, school, food storage areas

mechanical stripping of larger areas is necessary

patients, allergic person, persons with a low immune system

Risk potential

KEIM MycalMould renovation systemhydroactive - mineral - biocide-free

Mycal-FixSpore binder

Silicate pretreatment agent for the binding of fungal spores.

Spore flight is the main risk factor when removing mould. It endangers not only workers and people using the respec-tive room, but is also often the cause of consequential damage due to secondary contamination. It is for this reason that spore flight must be avoided at all cost when renovating surfaces infe-sted with mould.

•Mycal-Fixbindssporesonthe surfaces of building materials.•Mycal-Fix must be applied prior to removing mould-infested wall materials.•ThehighpHvaluealsohasa mould-inhibiting effect.

IMPORTANT:Dispose of building materials damaged by mould safely after removal.Building material infected with mould is a hazardous substance in accordance with hazardous substance regulations.

Mycal-Fix is also used to prime KEIM Mycal-CS and KEIM iPor panels.

Mycal-ExMould remover

Aqueous primer for the pretreatment of interior wall surfaces contaminated with microbes or residues.

The careful cleaning of surfaces contaminated with mould is a basic prerequisite for long-term renova-tion. Mycal-Ex is based on an oxi-dation agent and represents an environmentally safe alternative to products containing chlorine or biocides.

•Aqueous•Highoxidativeeffect•Compatiblewiththeenvironment because free of residue•Reactstowater•Chlorine-free•Highlydiffusible

Mycal-TopMould remediation paint

Highly specialised silicate paint for interior surfaces which combines dif-ferent approaches in terms of effect to mould contamination.

Standard paints available on the mar-ket for mould remediation always only apply one active principle:Anti-mould paints with special added active ingredients (e.g. fungicides) are for the most part inadequate in terms of building physics (no moisture regulation), products that are very good in terms of building physics, such as silicate paints with additional protective mechanisms, have not been available to date.

Mycal-Top is now setting a new standard:•Thehugediffusionpotentialandthe humidity-regulating properties ensure that walls stay dry thus minimising one of the main preconditions for the growth of mould, namely moisture. •ThehighalkalinityofKEIMMycal- Top counteracts any new infestation.•The inorganic structure demonstrably offers mould no nutrient base. •Byaddinganaturallyanti-microbially acting mineral, Mycal-Top provides additional protection against infestation.•Photocatalytically-activepigments also reduce harmful substances.•Wetabrasionclass1•Suitableforallergysufferers (according to test certificate)4

Mycal-PorSpecial lime render

Special mineral lime render for interior areas

Minimising moisture is the most important aim when combating mould infestation. Where larger areas are infested in particular, the paint base should be as sorptive and as moisture-regulating as possible

Mycal-Por •issorptive,capillaryactiveand moisture-regulating,•removesexcessivemoisturefrom ambient air and releases this quickly (minimises the risk of condensation).•Thehighalkalinitycreatesan additional alkali deposit.•Adhesivemortarproperties•MortargroupCSI•Grainsize0–0.6mm•Alsoforbondingandreinforcing Mycal-CS and iPor insulation panels (interior insulation panels)

Mycal-CS panelCalcium silicate insulation panel

Lightweight calcium silicate panel for increasing the surface temperature of walls

In the event of corresponding buil-ding conditions, increasing the surface temperature of interior walls may become necessary as a prerequisite for sustainable mould remediation.

•Lightweight,mineralcalciumsilicate panel•IncombustibleA1according toDIN4102•Preventscondensationandthusthe formation of mould.•Canalsobeusedtoimprove thermal insulation indoors.•Panelsize:62.5x100cm•Panelthickness:25mm

Mycal-CS insulation wedgesto reduce thermal bridges in ceiling and wall connecting areas and for visual alignment of abutting edges.

Mycal-CS reveal panel for window and door reveal areas.

Mycal-CS panelProcessing

Cut Mycal CS panels as required using a saw.

Pre-wet the adhesive side of panels using approx.1litreofwaterperpanel.

Apply Mycal-Por using a medium bed trowel by means of the notched trowel method fully covering the freshly primed panel (wet-on-wet). Press panels onto the substrate using slight pressure and float into position. Adhere the insulation panels offset. Shape butt joints using sealing tape or edge insulating strips.

CS insulation wedges and CS reveal panels are available where required.

Once the adhesive has been applied, prime the panel surface facing the room with Mycal-Fix and allow to dry.

Apply a full covering of Mycal-Por to the primed surfaces and embed KEIM glass fibre mesh. Observe drying times.

Plaster with Mycal-Por and paint with two coats of Mycal-Top.

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The special range of benefits offered by KEIM Mycal-Top has naturally been confirmed by impartial test certificates from well-known specialist institutes. This applies in addition to properties such as resistance to mechanical stress, wet abrasion, safe for use with foodstuffs, non-combustibility and suitability for allergy sufferers, and of course also in particular to its effect against mould.

As part of a comprehensive testing procedure in accordance with internati-onal standards (DIN, EN, ISO 846),MPA Bremen demonstrated that Mycal-Top “has a strong fungi static effect” (i.e. is highly resistant to mould) without the use of toxic biocides! The following images show the behaviour of KEIM Mycal-Top directly compared with a traditional interior dispersion paint.

After eleven days, there is already clear fungus growth in the dispersion paint. Fungus growth is also clearly visible on the edges of the paint sample.

The bowl containing KEIM Mycal-Top has no fungus infestation after the same period (eleven days). Both the nutrient base and the paint sample are free of fungus.

KEIM Mycal-TopEffectiveness guaranteed

Storage of paint in nutrient medium –without active “spiking” with fungus spores.

Storage of paint in nutrient medium –without active “spiking” with fungus spores.

Common dispersion paint – fungus infestations

KEIM Mycal-Top – fungus-free

Fungus growth in the nutrient base encroached

unimpeded on the test specimen.

There is solid mould growth in the immediate vicinity of the test specimen whilst the test specimen itself is completely free of infestation.

In a further test set-up, samples of the dispersion paint and Mycal-Top were spiked with the most commonly occurring forms of mould, i.e. aspergillus niger and penicillium funiculosum and

stored for three weeks at 95% humidity. The results speak for themselves:

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Dispersion paint – fungus infestations

KEIM Mycal-Topfungus-free

50% of the surface is infested. The dark fungus

hyphae are clearly visible.

No fungus growth is visible on the surface even under a microscope.

KEIMFARBENGmbH

Keimstraße 16D-86420 DiedorfFon +49 (821) 4802-0Fax +49 (821) 4802-210

Frederik-Ipsen-Straße 6D-15926 LuckauFon +49 (35456) 676-0Fax +49 (35456) 676-38

www.keimfarben.de info@keimfarben.de

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System solutions dependingon the hazard potential

Nutrients Moisture pH-value Temperature

Grade 1: Low risk

KEIM Mycal- Fix Spore binder Ex Mould remover Top Paint

Minimized by: mineral paint coat, anti-microbial mineral, photocatalysis

Minimized by: permeable and moisture-regulating paint coat

Alkalinity is a mould inhibitor

Grade 2: Medium risk

KEIM Mycal- Fix Spore binder Ex Mould remover Por Special lime render Top Paint

Minimized by: mineral paint coat, anti-microbial mineral, photocatalysis

Minimized by: absorbent, mineral render, moisture buffer and alkali depot

Alkalinity is a mould inhibitor

Grade 3: High risk

KEIM Mycal- Fix Spore binder Ex Mould remover Por Special lime render CS-Platte Insulation panel Top Paint

Minimized by: mineral paint coat, anti-microbial mineral, photocatalysis

Minimized by: absorbent, mineral render, moisture buffer and alkali depot

Alkalinity is a mould inhibitor

Increasing the wall surface temperature reduces the infestation risk.