Ambionse Building Blocks – FAQs

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Ambionse is a type of building block known as Insulated Concrete Formwork or ICF
ICF’s are simply formwork for concrete walls that remain in place permanently, as well as providing all the insulation for the walls
In NZ, ICF’s have also been called polyblocks.
As far as we can tell, the first ICF construction was in Wellington in the early 1980’s.
Ambionse allows you to create homes and buildings that are more energy efficient, stronger, more sound resistant, and more environmentally sustainable than if you use timber framing. Also Ambionse is faster, lighter, cheaper and warmer than conventional masonry
Ambionse provides an R-value of 3.0, while the Building Code requires a minimum house wall R-value of 2.0 for all NZ areas. 50% better R-value.
We like to consider Ambionse to be “blockwork for chippies”. All that is required is some trade experience and a bit of common sense. We do not recommend Ambionse as a DIY product because it is very difficult to undo a solid concrete wall.
It’s still relatively unknown to the general public and traditional builders, but we are in the business of changing that!. Another reason is that building an Ambionse home benefits the homeowner much more than the builder, particularly in the long-term. In the short run, it costs more to build and being less familiar to a builder means there could be more money for them in slapping up a timber frame home. So a builder who is unfamiliar with Ambionse and ICF’s in general is not going to educate their client about this far superior option. However, a builder who is experienced with Ambionse will appreciate the many advantages for both the builder and homeowner. Also we find that because of the minor learning curve and the great technical support available, any builder with some common sense would probably be willing to use Ambionse if requested.
Ambionse is proudly New Zealand made. Styrobeck Ltd manufactures the individual components as well as the Ambionse blocks in their facility in South Auckland.
We have developed a Training Programme to assist first-time builders, and whenever practical we will be on-site to advise as required. If you have a project coming up and would like a copy of the Training Programme on CD, then please let us know.
At this stage we do not have any non-specific designs, so an engineering design is required for all Ambionse structures. Any structural engineer should be able to design and Ambionse wall as the structure is conventional reinforced concrete.
The strength of the Ambionse wall is determined by the strength of the reinforced concrete. All structural connections are made to the concrete core, not the Ambionse block. The Ambionse block is designed to withstand the pressure from the wet concrete, but once it is cured, there is no strength consideration made.
Concrete has proven to be one of the best materials to resist sound transmission, so with a solid concrete core, an Ambionse wall will provide a sanctuary from the noises and distractions outside.
Ambionse is simply a means of constructing a solid reinforced concrete wall. Reinforced concrete is well established in New Zealand, so providing the details are sufficient there should not be issues with obtaining a Building Consent.
Even though the Risk Matrix was developed and only applies for timber frame structures, we still recommend that for Ambionse buildings it is used as a guide to sound design.
At this stage there are no non-specific design details available, so please refer to a structural engineer for reinforcing details. The engineer will need to know the 3 widths of the concrete core (90mm, 150mm and 200mm) and the limits on the reinforcing bar spacings which are dictated by the dimensions of the block and the bridge spacings:
the horizontal bars spaced at multiples of 300mm
the vertical bars spaced at multiples of 150mm
Ambionse tends to be a little bit more than most timber framed options, and less than the other concrete options for residential construction.
Obviously with any lightweight material the wind can be a nuisance. Part of the Ambionse construction process involves installing bracing. These braces are designed to keep the blocks in place, allow alignment of the wall, and provide a scaffold support when working at the top of the wall.
Over the last 20 years builders have been asked to build tighter wood homes using house wraps, seals and tapes to reduce the amount of air infiltration/loss (and therefore temperature change) in the home. When these products fail, moisture gets trapped inside the open cavity of a wood stud wall, causing mould and mildew problems and rot. Ambionse creates a complete envelope with no cavity, and concrete fills the entire core of the wall. Given that there is no place for moisture to travel in the wall, and that EPS, steel reinforcing and concrete are all three inorganic material, they are resistant to mould and mildew problems.
The points at which utilities connect to the building should be identified before the walls are constructed. This will allow for conduits to be placed through the wall as required so that the services can enter. Once the concrete is poured and cured, channels or grooves are cut directly into the Ambionse block using any of a variety of tools. Plumbing and electrical wires are then inserted into the grooves and covered by the plasterboard.