Sandwich walls precast three-layer panels
A finished facade straight from the mould
A sandwich wall is a well-insulated external concrete wall made up of a structural inner leaf, an insulation layer and an outer leaf that is durable and maintenance-free. The facing layer can be produced in a range of surface textures to suit the character of the building.
The insulation thickness reaches 300 mm, which allows very low thermal transmittance values. A residential building based on layered walls is airtight, durable and provides good sound insulation.
Properly designed, a sandwich wall can also resist earth pressure. On request we supply elements with cast-in electrical conduits, boxes and pre-fitted windows.
In design documentation this build-up appears as a three-layer wall or a layered wall with a concrete facing leaf — it is the same element.
Sandwich wall parameters
Elements are produced in accordance with EN 14992:2007+A1:2012, under assessment system 2+ and certificate 0761-CPR-1152 issued by IBMB MPA TU Braunschweig.
EN 14992:2007+A1:2012 · Assessment system 2+ · Certificate 0761-CPR-1152 · IBMB MPA TU Braunschweig
- Maximum element dimensions
- 3,85 × 9,00 m
- Structural leaf
- Min. 15 cm
- Outer layer
- 7 cm of facade concrete
- Insulation thickness
- Up to 300 mm, to the investor's specification
- Insulation materials
- EPS, XPS, PIR, mineral wool
- Concrete class
- LC20/22; C20/25 or higher
- Fire resistance
- R60–R240, EI30–EI60
- Sound insulation Rw
- Up to 50 dB
- All element edges are chamfered 1 cm.
- Smooth surface on the mould side (DF), the other side mechanically smoothed (GF).
- A sandwich wall can be designed to resist earth pressure.
- The structural leaf can also be made of expanded clay (LECA) concrete, which reduces the weight of the whole wall — see the material comparison on our expanded clay concrete page.
Solid, two-layer or sandwich?
Three build-ups of the same wall. They differ in how many layers are made in the factory and how many have to be completed on site.
Typical applications
The solution for buildings where speed of enclosing the shell and a durable facade with no finishing works matter.
Residential facades
An airtight, durable wall with a finished facing layer and good sound insulation.
Industrial buildings
Large facade areas enclosed quickly, with no scaffolding or wet trades on site.
Retaining walls
A variant designed to resist earth pressure, for example on basement levels.
Elements with windows
Available with factory-fitted windows and cast-in electrical services.
What determines the price of precast elements
Precast elements are not priced from a per-metre price list — every element is designed for a specific project, and the difference between two projects of the same floor area can reach several tens of percent. So instead of a rate, we explain what actually determines the figure in your offer.
We prepare a quote within about a week of receiving complete documentation: dimensioned floor plans, sections, elevations and the site location with a postcode. The offer covers production, transport and installation — each item is priced separately, so you can see where there is room for savings.
- Element repeatability
- The single biggest variable. The same element produced in a series is markedly cheaper than a one-off, because the mould and production set-up are spread across many casts. A design based on a few repeatable types works out cheaper than one with dozens of unique elements.
- Concrete class and reinforcement
- A higher class means more cement; higher loads mean more steel. Sizing for the actual loads, rather than with excess margin, can cut the cost without compromising the structure.
- Surface finish
- A smooth, as-cast surface from the mould is standard. Form-liner textures, acid etching or architectural concrete in category BA2 or BA3 require additional formwork and tighter controls, which shows in the price.
- Factory-fitted features
- Cast-in boxes, conduits, openings and corbels increase the element price but remove the cost of chasing and fixing on site. On larger series this usually works out cheaper than doing the work on site.
- Transport and size
- The price depends on the distance and the number of loads. Elements up to 3,85 × 9,00 m travel on a standard vehicle; larger ones require abnormal-load transport with an escort vehicle and permits, which changes the calculation significantly.
- Timing and season
- Production runs in parallel with the groundworks, so ordering early gives flexibility in the programme. Forced deadlines and next-day deliveries always cost more.
Technical drawings
Sections and connection details to scale — the same drawings that go into the technical catalogue. Numbers on the drawing refer to the list beside it.
- Top edge of element
- Side edges
- Mineral wool
- Bottom edge of element
- Door and window edges
We'll select the right elements for your project
Send us dimensioned floor plans, sections and elevations — we will prepare an element selection, a schedule and a quote. Preparing a quote takes around a week on average.