ᐅ Preparing a Split Air Conditioning System: Is Running Refrigerant Lines Through the Concrete Slab Advisable or Risky?

Hello everyone,

We are currently planning our new build (without a basement) and would like to prepare everything for a split air conditioning system. To route the refrigerant lines from the outdoor unit into the house to the indoor units, I plan to install the lines through a floor duct (this saves having a visible core drill hole through the exterior wall). When the foundation slab is poured, it would be no problem to install an additional single-duct house entry sleeve.

However, I can’t really find any information online about routing air conditioning lines through the foundation slab. Am I missing something? Is it not possible? Any disadvantages or risks?

If anyone has experience or knowledge about this, I would appreciate any information.

Best regards,
Tobias

The simplest and cheapest solution is to have an outdoor unit installed directly behind each indoor unit. It may not look very attractive, but it is not technically demanding, so anyone can install or repair it. If something breaks, replacements cost around 500–800 euros.
Given all the discussions about PPFAS, I would definitely avoid installing a large system at this time.
For cellar penetrations, make sure to ensure permanent waterproofing depending on the risk.