ᐅ How harmful to health is parquet adhesive when used with underfloor heating?

Hello,

this summer we are starting the construction of a semi-detached house and are currently deciding on the flooring. We have chosen to install tiles throughout almost the entire house, as they are considered the best option for heat transfer with underfloor heating. The exception will be our living/dining area, as we find tiles too cold for this 70 m² (750 sq ft) space and prefer wood for its warmer feel. For this reason, we have decided on solid oak parquet, which will be fully glued down using a parquet adhesive with a weight of 80 kg (176 lbs). I know that parquet is not the ideal choice for underfloor heating but it is still feasible.

While researching online, I came across some articles claiming that parquet adhesives can be toxic, which has left me a bit concerned. Could this issue be worsened by the underfloor heating warming up? Will the adhesive off-gas and release “toxic fumes” into the room? Or are modern parquet adhesives generally safe? I have read about the EC1 and EC1 Plus standards. Does choosing an adhesive with such certification ensure safety?

I would appreciate a brief assessment.

Best regards,
hansmuff

I have recently been looking into this because we are having fully glued parquet flooring installed in a few weeks, and I couldn’t find any information about the toxicity of current parquet adhesives. It seems that many older installations used adhesives that were toxic, but not the ones used today.
Do you have any sources (please do not post links, just how to find them)?

I installed the floor as a floating floor over underfloor heating. This way, the floor has a slight give, and no adhesive is needed. It works well and was also somewhat cheaper in terms of installation labor.

I can imagine that you have a few weeks between laying the hardwood flooring and moving in, assuming proper ventilation, so the harmful gases can dissipate. New furniture is actually worse.

The last time I looked into this topic was in 2018, and at that time: Ökotest and Warentest had tested parquet adhesives multiple times and could not identify any adhesives without harmful emissions... and these do not disappear after just a few weeks. Since wood expands and contracts, the adhesive must be able to withstand much more stress than those used for linoleum or, for example, PVC/vinyl/"luxury vinyl tile" (which also has its own issues with harmful substances).

By the way, small children often spend a lot of time close to the floor and are therefore very exposed to these emissions...

hansmuff schrieb:

Will the adhesive evaporate and release "toxic gases" into the room? Or are modern parquet adhesives safe? I have read something about the standards EC1 and EC1 Plus. Does using an adhesive with such certification ensure safety?

Modern parquet adhesives are just as hazardous as tile adhesives or vinyl flooring (now often called luxury vinyl flooring).