In recent years, particularly in the public sector, there is just no avoiding exposed concrete. Architects enjoy the purist impression provided by using concrete as a construction material, which is in line with the clear design language that is so beloved these days, and gives buildings an urban appearance.
The challenging in using this construction method is that the electrical installation must be considered right from the formwork stage. Thus boxes and conduits are embedded so that they will later be in precisely the right location and – apart from the required controls – no trace of them is visible.
In modern practice this uses special installation methods which work, for example, with support spars. These are clamped between the two formworks, where they fix the conduits and boxes in situ. However, this technique does not always lead to satisfactory results, as it often mars the surface on the back of the spars. If this wall is later to remain visible, then time-consuming reworking of the surface is necessary to remove the marks from installation.
As a specialist in user-friendly enclosures, Spelsberg has come up with some new ideas in this area and developed another solution entirely:
The new reinforcement box does without aids such as support spars, and is instead clamped directly into the reinforcement using a patented technology and secured with tie wire. Grooves ensure that the box is firmly engaged in the reinforcement and is even able to tolerate different iron thicknesses up to 18mm.
What makes the Spelsberg solution stand out is a newly developed spring system. It offers the maximum in flexibility without the risk of parts breaking off, and therefore not being able to withstand the pressure from the concrete during pouring. Even during insertion, the spring-loaded mounting kit can be conveniently folded to one side. This enables any box to be correctly positioned and fastened in place in seconds. Like a shock absorber, the spring system compensates for different depths of concrete coverings from 20-60 mm with no problem, and ensures optimum contact pressure on the formwork at all times.
For combining multiple boxes combi cams have been integrated into the new reinforcement box, to create the precise spacing required between the individual enclosures without the need for additional accessories, and to reliably maintain it during pouring.
For launch it will initially be available in a traditional 35mm wall outlet box and a traditional 60mm box, which are supplied ready for installation. As is customary for Spelsberg, however, the new reinforcement box was not developed as a standalone product. Rather it is part of the tried-and-tested IBT system. A universal reinforcement adapter ensures that it is possible to insert and use all U71 boxes of the IBT series, apart from the Perilex equipment box. This means that the new system will immediately offer a wide variety of installation options and heretofore unseen levels of flexibility. You can still react to planning changes when on site, and fit other boxes to the adapter if necessary. In addition a deep box is available, which can be used to extend the box back into the wall, for example to achieve large mounting depths.
This modular construction means that the system is clearly laid out and does not result in unnecessary ballooning of warehouse space for wholesalers and tradesmen.
To simplify installation even further, Spelsberg uses a universal system of colour-coding, whereby the base of the boxes is always green and the front always blue. This makes it possible to intuitively hold and use the enclosure in the right way, without having to examine it more closely during installation. Thus a major source of error is ruled out.
A wide array of inserts for the conduits further reduces the install time – making it a particularly easy task to insert the conduits into the spring-loaded box. The fully insulated cable transfer point also creates a closed system, guaranteeing a high level of leak-tightness and maximum protection against the penetration of concrete.