ᐅ Insulating plastic fittings/water pipes and underfloor heating under the screed?

Hello,

as shown in the two photos, the hot and cold water pipes are insulated. The plumber says the fittings (connectors) do not need to be insulated because they are made of plastic. Is this correct, or could this cause problems regarding thermal insulation, condensation, or noise?

The pipes are located under the screed, meaning there will be polystyrene insulation and a self-leveling screed on top.

The plumber suggests he could wrap fleece over them, but says it is not necessary. What is your opinion?

Best regards, Andreas

What is the thickness in centimeters of the insulation (thermal resistance level) around the pipes?

The pipes are pre-insulated Rehau Rautitan pipes. However, the connectors (plastic) are not insulated.

The insulation consists of closed-cell PE foam with a co-extruded, moisture-resistant PE film (see also photo).

I'm not an expert, but the insulation looks rather thin. I couldn't quickly find any datasheets.

Hello

I’m not exactly sure how this is done in Austria, as I have always done it the way it is done in Germany.
The insulation thickness seems to be only 50% of what it should be. This is definitely not sufficient for pipes that carry hot water.

Olli

The rooms have underfloor heating. I think 50% should be sufficient (according to Diddi Dämmmeister).
But is it worthwhile to insulate the fittings as well, or is it even necessary?