The less heating demand there is for a house, the more suitable surface heating and cooling systems are. How much economic sense this makes depends considerably on the pipe material. Polybutene (PB) piping as used in Viega's Fonterra surface heating and cooling systems provide a lot of benefits during installation. Even at temperatures down to -5 °C these pipes can be installed with small bending radii.
Surface heating and cooling systems such as Viega's 'Fonterra' range are gaining ever larger shares of the market in new constructions. In Germany, for instance, the share is already around 50 percent (source: BVF). The reason: No other method of heat distribution with low supply temperatures (< 35 °C) is as efficient. For this reason, surface heating systems are often combined with regenerative heat generators such as geothermal heat pumps or thermal solar plants.
In order to be able to exploit these effects, surface heating systems on stapled plates or snap plates must be laid as closely as possible in serpentine patterns. Ten years ago, the standard laying spacing in residential rooms was still 20 centimetres. Today, the spacing has gone down to only 15 centimetres, leading to improved energy saving and more uniform heat distribution.
Still at an advantage even in difficult conditions
Whether or not such close laying can be done easily and quickly under the often adverse conditions of a building site depends to a great extent on the flexibility of the pipe material: As well as the smallest bending radius that the material allows, another factor is its restoring capacity — in other words its tendency to return to its original shape after being bent. And these two factors are connected, as the pipe material polybutene shows.
Fonterra PB pipes can be bent to a very tight radius even at low outside temperatures down to about -5 °C. This makes laying them much easier. Especially as the pipe with its material and its relatively thin walls displays only a low restoring capacity. So once it has been laid in form, that is where it stays on the system panel. It is not even necessary to use extra fixing material, which saves more time. Also, insulation panels do not get pushed up on account of the restoring forces, as is the case with stiffer pipe material. And that, in turn, makes the screed layer's task easier. The screed can be laid properly and uniformly over the radiant heating coils without the risk of cracks forming.
The Fonterra range
Viega's Fonterra range consists of around twelve different systems in total for all kinds of different applications, ranging from residential housing to industrial use and to installations in sports facilities.
As an example, the Fonterra Reno system was developed specially for renovations without the use of screed. A feature of this dry floor heating system is the low total height of the construction. In addition, the plaster board can be laid directly, saving time and material. These advantages apply to the Fonterra Side 12 wall system as well: The 12 x 1.3 PB pipes are already integrated into the handy wall heating panels, making for very fast dry construction. And it saves a lot of smoothing work.
For floor installation in brick-based constructions, Viega supplies the variants Fonterra Base 12 and Fonterra Base 15 with snap plates as well as Fonterra staplers. This system allows for very flexible and exact cutting to size that exactly fits the shape of the room.
The Fonterra Base Roll 15 system combines the installation benefits of surface heating systems for stapled plates and snap plates:
The snap system panels are delivered in 2 x 5 metre, folded lengths and rolled out like stapled plates. This requires only one person. Then the 15 x 1.5 mm polybutene pipe is simply fixed to the system panels by foot pressure. Pre-assembled clips ensure that the piping is firmly fixed.
As every centimetre counts when it comes to installing surface heating in existing rooms, Viega has also developed the Fonterra Base Flat 12 variant: It is let into cement screed with a tested additive just like a standard wet construction system. This tailored combination of snap plate system, 12 x 1.3 mm polybutene pipe and the screed covering has a total construction height without insulation of only 35 mm. If factory-processed, 11 mm thick insulated Fonterra snap plates are used, the thickness is 45 mm in total. In both cases, 15 mm of screed suffice to cover the snap plates and to fulfil all the requirements for private residential rooms with an approved load capacity of 2 kN.
Fonterra Side 12 Clip, on the other hand, is for on-site wall mounting. It is integrated into standard interior plaster. In this case, special clamping rails are fixed to the shell wall, and the Fonterra pipe only needs to be unrolled and clipped onto them. This means that the available area can be exploited in the best possible way.
To complete the Fonterra range, Viega supplies manifolds, room thermostats, control stations, manifold cabinets and controllers. A completely new addition to the range is Fonterra Smart Control — a room-by-room regulation system that sets individual heating circuits of surface heating and cooling systems automatically. To this end, the controller not only continuously monitors the supply temperature at the manifold and the current room temperatures, but also the return temperature of each heating circuit. This ensures that the hydraulic compensation is carried out automatically. At all times, just enough energy is supplied to meet the current demand. The new room-by-room regulation system also takes account of construction parameters such as laying spacing and flooring types. This makes Fonterra Smart Control the ideal choice for refurbishments.
