INstallation Principles Thermal insulation of hot water pipes minimum insulation thickness in [mm] against condensation
Medium temperature 5°C - thermal conductivity value of insulation 0,040 W/mK Dimension humidity
ambient temperature 20°C
50% 75mm
22°C
24°C
26°C
28°C
30°C
32°C
34°C
36°C
38°C
40°C
1
1
2
2
3
3
4
4
5
5
3
3
4
5
5
6
7
7
8
8
60%
2
70%
5
6
7
8
8
9
10
11
12
13
13
80%
9
11
12
14
15
17
18
19
20
21
22
1
2
2
3
3
4
4
4
60%
1
2
3
3
4
5
5
6
7
7
8
70%
4
5
6
7
8
9
10
10
11
12
13
80%
9
11
12
14
15
17
18
19
20
21
22
1
1
2
2
3
3
50% 110mm
50% 160mm
60%
1
1
2
3
4
4
5
5
6
7
70%
3
4
5
6
7
8
9
9
11
11
12
80%
8
10
11
13
14
16
17
19
20
21
22
The decree for energy saving thermal protection and energy saving technique for buildings Decree for Energy Saving (EnEV) regulates the thermal insulation of hot water supplies and fittings in Germany. Central heating pipes, line 1 - 4 installed in heated rooms or building parts between heated rooms of the one user, where heat output can be controlled by open stop valves do not require a minimum thickness of the insulation. This even applies to hot water pipes up to an inner diameter of 22 mm in flats, which are neither in the circulation nor have an additional electric heating.
Applying material with thermal conductivities different to 0.035 W / (mK) the minimum thickness of the insulation has to be converted correspondingly. For the conversion and the thermal conductivity of the insulation the ways and values of calculation described in the technical regulations must be applied. The minimum insulation acc. to the table for heating distributions and heating pipes can be reduced as far as the same limit of heat output even for further insulation requirements in consideration of the insulating effect of the pipe walls are guaranteed.
EnEV 2009, § 14, addendum 5, chart 1 Line
Type of pipe / fitting
minimum thickness of insulation referred to thermal conductivity of 0.035 W / (mK)
1
inner diameter up to 22 mm
20 mm
2
inner diameter more than 22 mm up to 35 mm
30 mm
3
inner diameter more than 35 mm up to 100 mm
same as inner diameter
4
inner diameter more than 100 mm
100 mm
5
pipes and fittings after line 1 - 4 in wall- and ceiling openings, in crossing area of pipes, at pipe connections, at distributors
1
6
pipes of central heating after line 1 - 4, which have been installed after introduction of this decree between heated rooms of various users
1
7
pipes after line 6 in floor construction
6 mm
8
Cooling distribution and cold water pipes and fittings of air handling and air conditioning systems
6 mm
/2 of the requirements of line 1 to 4
/2 of the requirements of line 1 to 4
79