ᐅ Floor construction with ventilation system on the upper floor
Created on: 25 Mar 2018 21:04
P
pguerret
Hello,
for our planned single-family home (urban villa, 2 stories without a basement), which will be built by a developer, we want to install a mechanical ventilation system with heat recovery. The ventilation installer would like to use oval ducts measuring 115x51mm (4.5x2 inches) in diameter. These ventilation ducts are intended to be installed within the floor structure of the upper floor, between the concrete slab and the screed. The floor structure currently looks like this:
- 1.0 cm (0.4 inches) surface covering
- 6.5 cm (2.6 inches) cement screed CT-C25-F4 with fibers S65 H45
- 10.0 cm (4 inches) impact sound insulation
- 18.0 cm (7 inches) reinforced concrete slab C20/25
Now the construction manager has expressed concerns and says the floor structure needs to be raised by 4 cm (1.6 inches), which would increase costs by around 1200 euros.
If I understand correctly, the ventilation ducts (5.1 cm (2 inches) in height) would have sufficient insulation both above and below (within the 10.0 cm (4 inches) impact sound insulation). I have illustrated this in the attached image. Is there something fundamentally wrong here?
Thank you for your advice.
for our planned single-family home (urban villa, 2 stories without a basement), which will be built by a developer, we want to install a mechanical ventilation system with heat recovery. The ventilation installer would like to use oval ducts measuring 115x51mm (4.5x2 inches) in diameter. These ventilation ducts are intended to be installed within the floor structure of the upper floor, between the concrete slab and the screed. The floor structure currently looks like this:
- 1.0 cm (0.4 inches) surface covering
- 6.5 cm (2.6 inches) cement screed CT-C25-F4 with fibers S65 H45
- 10.0 cm (4 inches) impact sound insulation
- 18.0 cm (7 inches) reinforced concrete slab C20/25
Now the construction manager has expressed concerns and says the floor structure needs to be raised by 4 cm (1.6 inches), which would increase costs by around 1200 euros.
If I understand correctly, the ventilation ducts (5.1 cm (2 inches) in height) would have sufficient insulation both above and below (within the 10.0 cm (4 inches) impact sound insulation). I have illustrated this in the attached image. Is there something fundamentally wrong here?
Thank you for your advice.
Eldea schrieb:
In our case, the pipes are laid directly on the concrete, with insulation placed between and on top of them, followed by the underfloor heating.Thanks for the pictures! Do you have a (heated) basement? How many cm (inches) thick is the insulation layer on the ground floor? What was the floor structure like on the upper floor?
pguerret schrieb:
So, in your case the pipes are installed directly on the ceiling, meaning on the solid wood without any insulation underneath and only insulation/fill material above?Yes. The fill material fits snugly around the pipes. Both the fill material and the screed are floating.
B
Benutzer 100326 Mar 2018 09:02Hello forum,
The required minimum thickness of the screed is regulated in
DIN 18560, Part 2, "Screeds and heated screeds on insulation layers."
For an expected load in residential areas of 2.00 kN/m² (42 psf), Table 1 specifies the following values for cement screeds:
Minimum thickness >45 mm (1.8 inches)
Minimum flexural tensile strength F4
Therefore, the original floor structure with 65 mm (2.6 inches) is completely sufficient.
With proper installation, no problems typically arise with the chosen construction based on experience.
In this context, the installation of thermal insulation and ventilation pipes should be carried out as carefully as possible to reliably ensure load transfer. It is important to avoid cavities during installation.
Kind regards
Kristof
The required minimum thickness of the screed is regulated in
DIN 18560, Part 2, "Screeds and heated screeds on insulation layers."
For an expected load in residential areas of 2.00 kN/m² (42 psf), Table 1 specifies the following values for cement screeds:
Minimum thickness >45 mm (1.8 inches)
Minimum flexural tensile strength F4
Therefore, the original floor structure with 65 mm (2.6 inches) is completely sufficient.
With proper installation, no problems typically arise with the chosen construction based on experience.
In this context, the installation of thermal insulation and ventilation pipes should be carried out as carefully as possible to reliably ensure load transfer. It is important to avoid cavities during installation.
Kind regards
Kristof
Similar topics