WDVS -> Polystyrene -> Hexabromocyclododecane (HBCD) and biocides!?

Good morning,

my wife and I have currently secured a house in a small new housing development.

In the construction and service description it states that "WDVS" is used as the exterior plaster. We suspect that a typical WDVS with polystyrene is used here. Information on the internet unsettles us because the flame retardant hexabromocyclododecane (HBCD) is classified as an environmental toxin. Additionally, it is mentioned there that biocides are used in the insulation material to prevent algae and mold infestation.

I would be interested to know if this is generally always the case when it comes to the generic term "WDVS"? I have already confronted the developer with these questions, but I would also like to learn from the experts in the forum whether it is really that critical? What is your opinion on this matter? Should the health aspect possibly also be taken into account?

Or is it "not such a big deal"? When you consider how many houses in Germany are/would be affected by this...

Best regards & thanks for the help! Gatho

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link removed by moderation; please observe the forum rules.

Thank you very much!
Construction expert

Hello,

thanks Bauexperte for the improvement, I had missed that no links are allowed - sorry. :/

Please just enter "NDR Polystyrol" in Google. The first link fits the topic.

Best regards
Gatho

I would be interested to know if this is generally always the case when it comes to the generic term "WDVS"?

Instead of combustible plastics, ETICS can also be made with mineral or natural building materials. AFAIK, there are also mineral wool insulating boards that can be plastered over. In cavity wall construction, mineral wool can of course also be used for insulation. Then there are perlite, expanded clay, etc. Or wood fibers (well, are they combustible?), and so on. Biocides should, if at all, be used superficially in the plaster. In my opinion, this has nothing to do with ETICS. Tip: Build cavity walls with facing bricks. Or timber frame construction. When building with a developer, you might be able to build with facing bricks and then get mineral insulation. That will be expensive (especially with a developer). Oh, and in a house legally built today with legal building materials, there should be no hexabromocyclododecane. It has been banned since 2013.

Hi Gatho,

I agree with Bieber0815, to avoid combustible materials in the ETICS, you can either

· Insulate with mineral wool instead of polystyrene

· Build monolithically (Poroton or similar)

· Build double-shell with clinker and mineral wool in between (this also avoids biocides in the plaster)

build

All of these will require significant additional costs, if your general contractor/general planner/developer even offers it. And with the "monolithic" solution you even pay for worse insulation values.

Every solution has advantages and disadvantages, and you will always find someone who says, “but this is toxic and that could happen here.”

However, you should always see this in the context of today's analysis methods and possibilities. Today, we call many things "dangerous" and subjectively feel that we are constantly being poisoned by something everywhere. But this is simply because today you can detect pollutants in such low concentrations that they are far, far below any danger threshold.

Many of the materials used in our parents' houses, in which we have all lived for decades, are now considered highly toxic hazardous waste. Smoking was once considered healthy, and the wood preservatives my father used to paint the garden fence probably killed every bark beetle that even saw the fence...

Don't get me wrong, the fact that we are smarter today and avoid these dangers is absolutely right and commendable. But maybe today we often overshoot the mark. Compared to earlier times, we live in a very healthy and ecological environment. Remaining dangers should be eliminated where possible, but we are at a level where scaremongering very often prevents correct and prudent consideration.

I stay out of the discussion on whether polystyrene should be treated as hazardous waste in the future or whether HBCD is really toxic. The LD50 lethal dose for rats is over 10 g per kg of body weight. Converted for a human, that would be about 700-800 g. The lethal dose of table salt is probably significantly lower...

Therefore, I have decided to classify the topic as "not so bad" for myself, and yes, we are building with a polystyrene ETICS.

Whether this is really right, ask me again in 30-40 years.

Best regards,

Andreas

Poisons in the plaster are not necessary, by the way, if you use a mineral high-quality scratch plaster. Then you no longer need the chemical club...

Regarding the topic [WDVS], a marketing war is raging in the media. Rockwool, the world's largest manufacturer of insulation systems made from stone/glass wool, is fueling negative campaigns against EPS. The EPS lobby, in turn, responds with campaigns against mineral fibers. The consumer hardly has a chance to make a reasonable decision here. It is important that the insulation is installed professionally. The lung-damaging fibers in mineral wool should of course not float around in the living space afterward. For EPS insulation, it is important that appropriate fire barriers are installed if necessary, etc. If this is taken into account, in my opinion, one is sufficiently protected by the German legislator and can choose their insulation system based on cost-effectiveness and personal preferences without harming their own health or the health of their family.