ᐅ Allegro-Haus Ltd. Experiences

Condor schrieb:
...Underfloor heating is one thing, and water supply for showers and so on is another. The water temperature produced by the heat pump will not exceed a certain value.

Correct, that’s why heat pumps are particularly efficient when the flow temperature (FT) is as described above (heating mode). For domestic hot water, the temperatures are naturally higher. Sensibly, a maximum of 50–55°C (122–131°F) is recommended. This means the hot water storage tanks must be properly sized or there should be a fresh water system. Therefore, the annual performance factor for domestic hot water production is somewhat lower, which under “normal” conditions usually does not have a big impact, since the annual energy share for heating is usually higher. All this can be clarified in advance (preliminary investigation).

Condor schrieb:
...Which heating type is the most economical if we exclude gas.

There is no “most economical” heating system! Each construction project has different conditions depending on the specific framework. What makes sense for A might barely work for B and lead to high costs for C.

Condor schrieb:
...The standard is supposed to be an air-to-water heat pump, or should one rather prefer a ground-source heat pump with deep boreholes?

No one can provide a reliable answer to that => preliminary investigation.

Condor schrieb:
...Are there any experiences regarding the noise levels of both heating systems?

Ground-source heat pumps probably have the advantage here, also due to indoor installation. For air-source heat pumps, it depends. More efficient, fully modulating split units have the evaporator in an outdoor unit. There are also combination units (indoor installation) that deliver significantly lower performance factors but are quieter outside.

So this also depends on the specific conditions. In an absolutely quiet location, the outdoor evaporator can sometimes be perceived as annoying. Then a ground-source heat pump can also be used with a source that does not require “digging or drilling.” However, the performance factors are lower compared to a ground-source heat pump with, for example, a vertical probe.

As you can see, everything has certain advantages but also disadvantages. Proper assessment and evaluation are only possible with a solid and precise preliminary investigation as well as overall planning.

Thanks first of all for your advice, more questions will certainly follow.

Best regards and have a happy Ascension Day

€uro schrieb:
Correct, heat pumps are especially efficient when the flow temperature (FT) is as described above (heating mode). For domestic hot water, temperatures are naturally higher, ideally max. 50–55°C (122–131°F). This means that hot water tanks need to be sized accordingly or alternatively a fresh water system used. Therefore, the annual performance factor for hot water production is somewhat lower, which usually doesn’t have a significant impact under normal conditions, as the share of annual energy consumption for heating is typically higher. All of this can be clarified in advance (preliminary investigation).

A bit more about underfloor heating:

We are currently considering the flooring for the living room, about 30m² (320 sq ft). We are facing the choice between tiles or traditional laminate, parquet, bamboo, or cork.
I am not sure if I’m correct here:
The advantage of tiles is that they are more durable and don’t show scratch marks, retain heat longer, and are moisture-resistant, but they are also quite expensive.
The advantage of the other flooring types is that they offer a wider range of design options.
Is the difference in heat retention really something to prioritize, or can it mostly be neglected?

Who has experience in this area?

Thanks for your feedback.

Best regards

Condor schrieb:
...Advantages of tiles: they are more durable and don’t leave scratch marks, retain heat longer, and are resistant to moisture but also quite expensive!

Advantages need to be considered from different perspectives. Tiles have particularly high thermal conductivity, making them, from an energetic standpoint, the "ultimate" covering for underfloor heating. Other floor coverings generally have higher thermal resistance. However, the visible light transmittance (VLT) also plays a significant role. For example, with heat pumps (HP) as the heat source, having warm feet on tiles is more of a wishful thinking.
The heat storage (thermal inertia) is mainly not in the covering, but in the screed!

Best regards

Thank you for your detailed explanation. As a beginner, you really have to navigate through this maze, so any good advice is helpful.

Another issue: our house is planned to have a cold roof. Since the bathroom is located on the upper floor, I am concerned that there might be condensation problems on the ceiling during winter. Should the roof be insulated?

Can a cold crawl space actually be used as a storage area? I am worried that moisture might settle there. For this reason, I am considering having the floor insulated without extensive cladding so that it can be used for storage. Is the effort worth it? What kind of costs should be expected for a basic floor plan of 8 x 10 m (26 x 33 ft)?

Thanks for your feedback.

Best regards

Either you insulate the roof or the ceiling below. If done properly, you won’t have any condensation in the bathroom. But if the ceiling insulation is done poorly... it’s like “it’s raining man”...

With a cold roof, you need to make sure, for example, that you don’t install OSB boards (use tongue-and-groove boards instead) and also avoid installing flooring within 10cm (4 inches) around the edges. This way, it stays dry up there, and you can use the cold roof as storage space—though only for items that are not affected by heat or cold. There are special storage bags for that...

I would keep the cold roof, as it has some advantages. The biggest benefit is that on the upper floor, it’s only as hot as the outside in the shade. Anyone who has ever lived in an attic apartment knows what I mean.