ᐅ Change the spacing of underfloor heating pipes

Good morning, I am currently building a single-family house to KfW55 standard with a general contractor, approximately 120 sqm (1,290 sq ft) over two floors. The price includes underfloor heating with a pipe spacing of 15 cm (6 inches), and 10 cm (4 inches) spacing in the bathroom. In many threads, a pipe spacing of 10 cm (4 inches) is recommended for all rooms. This requires about 3 m (10 feet) more piping per square meter. In your experience, what additional cost per square meter should I expect if the pipe spacing is reduced from 15 cm (6 inches) to 10 cm (4 inches)? I am waiting for the offer from the general contractor but would just like to know what the cost increase might be based on your experience. Once I have the offer, I will share the actual additional costs with you.

The installation spacing should actually be determined through a heat load calculation and not just set arbitrarily… also, it depends on what type of heating system you have. Do you have a heat pump?

In the end (preferably right from the start), every heating system will be operated with a heat pump. Therefore, it makes sense to aim for the smallest possible pipe spacing now. And yes – it is best if all circuits are of similar length and the rooms are calculated individually beforehand. 10 cm (4 inches) spacing is usually fine. Less is better; 15 cm (6 inches) would be too wide for me.

In the bathroom, it is best to include an extra wall, as otherwise it often is not sufficient.

Snowy36 schrieb:

Do you have a heat pump?

Yes, an air-to-water heat pump from Buderus is being installed.

Don't think that the price should make a difference whether it's 15 or 10.

Snowy36 schrieb:

I don't think there should be a price difference between 15 or 10

That would be nice, but I don’t think so. You need more piping, it has to be stapled more often, and that also requires more time.