Solid walls precast single-leaf panels
Where are solid walls used?
A solid wall is a single, monolithic reinforced concrete slab. It most often serves as a party wall between flats, a lift shaft wall or a stabilising element of the structure. Used as an external wall, it is completed on site with a layer of insulation and render.
Properly designed, it can also resist earth pressure, which makes it suitable as a retaining wall — for example in underground car parks. Inside a building, the same element acts as both a fire and an acoustic barrier.
In project documentation you will also come across the terms single-leaf wall, precast concrete wall or reinforced concrete wall — they all describe the same product in different words.
Solid wall parameters
Elements are produced in accordance with the harmonised standard 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
- Element thicknesses
- 10, 12, 15, 18, 20 and 24 cm
- Lightweight concrete class
- LC12/13 D1,4 or higher
- Normal-weight concrete class
- C20/25 or higher
- Surface
- Smooth on the mould side (DF), the other side mechanically smoothed (GF)
- Edges
- Optional 1 × 1 cm chamfer
- Factory-fitted features
- Cast-in electrical boxes and conduits, window and door openings
- Reinforcement
- To the structural calculations and reinforcement drawing
- Elements larger than 3,85 × 9,00 m are made to special order only.
- Installation corbels are made on the smoothed (GF) side only.
- Service chases are agreed individually at the shop drawing stage.
- LC classes denote lightweight concrete on expanded clay aggregate — its properties are described in detail on our expanded clay concrete page.
Sound insulation of solid walls
Rw is the single-number weighted sound reduction index, and R'A1 is the approximate airborne sound insulation of the wall in a building, allowing for flanking transmission. The values are based on laboratory tests and design calculations.
| Concrete class | Thickness [mm] | Mass [kg/m²] | Rw [dB] | R'A1 [dB] |
|---|---|---|---|---|
| LC12/13 | 100 | 140 | 39,3 | 34,3 |
| LC12/13 | 120 | 168 | 42,3 | 37,3 |
| LC12/13 | 150 | 210 | 46,0 | 41,0 |
| LC12/13 | 180 | 252 | 49,0 | 44,0 |
| LC12/13 | 200 | 280 | 50,7 | 45,7 |
| LC16/18 | 100 | 160 | 41,5 | 36,5 |
| LC16/18 | 120 | 192 | 44,5 | 39,5 |
| LC16/18 | 150 | 240 | 48,2 | 43,2 |
| LC16/18 | 180 | 288 | 51,2 | 46,2 |
| LC16/18 | 200 | 320 | 52,9 | 47,9 |
| LC20/22 | 100 | 180 | 43,5 | 38,5 |
| LC20/22 | 120 | 216 | 46,5 | 41,5 |
| LC20/22 | 150 | 270 | 50,1 | 45,1 |
| LC20/22 | 180 | 324 | 53,1 | 48,1 |
| LC20/22 | 200 | 360 | 54,9 | 49,9 |
| C20/25 | 100 | 235 | 47,9 | 42,9 |
| C20/25 | 120 | 282 | 50,9 | 45,9 |
| C20/25 | 150 | 352,5 | 54,5 | 49,5 |
| C20/25 | 180 | 423 | 57,5 | 52,5 |
| C20/25 | 200 | 470 | 59,3 | 54,3 |
The figures above are calculated. Those below are measured: in May 2025 the KFB Acoustics laboratory tested our walls to PN-EN ISO 10140-2:2021-10, on elements assembled to our installation manual — joints grouted with expansive concrete and a floor movement joint. Where both numbers exist, the measurement came out 2–4 dB higher than the calculation. Reports no. 0166-25P-T42-1-001a to -005a.
| Thickness | Concrete class | R'w (C; Ctr) | R'w + Ctr |
|---|---|---|---|
| 160 mm | C30/37 | 54 dB (−1; −4) | 50 dB |
| 180 mm | LC16/18 D1,6 | 55 dB (−1; −5) | 50 dB |
| 180 mm | LC20/22 D1,8 | 55 dB (−1; −4) | 51 dB |
| 180 mm | C30/37 | 59 dB (−1; −4) | 55 dB |
REI class by wall thickness
Fire resistance classes of load-bearing concrete walls according to Table 5.4 of EN 1992-1-2, fire on one side: minimum thickness and axis distance a of the reinforcement at the load utilisation level μfi. The Formee catalogue gives the range R60–R240 and EI30–EI60; the structural leaf thickness is matched to the required class at shop-drawing stage. Expanded-clay concrete walls are assessed with the same tables, with a margin, because lightweight concrete heats up more slowly. The class of a specific element is set by the structural design and reinforcement drawing.
| Class | μfi ≤ 0.35: thickness / a [mm] | μfi ≤ 0.7: thickness / a [mm] | Formee thicknesses for μfi ≤ 0.7 |
|---|---|---|---|
| REI 30 | 100 / 10 | 120 / 10 | 12, 15, 18, 20, 24 cm |
| REI 60 | 110 / 10 | 130 / 10 | 15, 18, 20, 24 cm |
| REI 90 | 120 / 20 | 140 / 25 | 15, 18, 20, 24 cm |
| REI 120 | 150 / 25 | 160 / 35 | 18, 20, 24 cm |
| REI 180 | 180 / 40 | 210 / 50 | 24 cm |
| REI 240 | 230 / 55 | 270 / 60 | to order, ≥ 27 cm |
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.
What we agree at the ordering stage
Beyond the dimensions and concrete class, every element is defined by a handful of execution decisions. We make them together at the shop drawing stage.
Visible face
The mould-side surface (DF) is smooth; the opposite face (GF) is mechanically smoothed. You tell us which side will remain exposed.
Edges
Sharp as standard; chamfered with a 1 × 1 cm fillet on request. Chamfering hides minor chipping during installation.
Services
Boxes, conduits and penetrations are set in place before concreting, following the routed services layout.
Corbels and accessories
Installation corbels are made on the smoothed (GF) side only — this constrains the element's orientation on site.
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.
Solid walls — questions
The questions investors and contractors ask most often. Yours is not here? Write to us — we'll give you a straight answer.
- How are precast walls connected?
- On site, at joints set out in advance in the shop drawings. The vertical joint between adjacent elements has a profiled recess holding the reinforcement and the force-transferring shear keys — and it is grouting that recess, not the plates merely meeting, that makes the wall act as a continuous diaphragm. Joint concrete normally has a maximum aggregate size of 8 mm, matched to the geometry of the recess, with its strength class set by the design. The connection to the foundation and to the storey above runs through the ring beam and projecting reinforcement, and the floor bears on the wall in line with the reinforcement drawing. The quality of that grouting is a structural value here, not a cosmetic one — which is why industry guidance treats it separately, together with material requirements and execution control.Source: Betonelement-Foreningen, BEF Bulletin no. 5 — Sammenstøbning af betonelementer (2019)
- How much does 1 m² of precast wall cost?
- A price per square metre is not quoted in isolation from the design, because the same square metre costs differently depending on what it contains. Element thickness, concrete class, amount of reinforcement, the number of window and door openings and the extent of services cast in the mould all feed into it. To compare with masonry, cost the whole stage rather than the material alone — a precast element already contains what several trades carry out on a masonry site. We prepare a quotation from dimensioned plans and sections, usually within about a week.
- How are walls secured during erection?
- With diagonal props, until the joints have gained strength. Industry guidance assumes two props per element, placed symmetrically, with anchor points at no less than two thirds of the element height — lower down, the forces in the prop and the anchor rise. They are designed for wind load and for the eccentricity of self-weight, and when wind speeds above the warning thresholds are forecast the erector strengthens the bracing or stops work. That is why the crane position and the erection sequence are planned together with the propping: an element does not stand on its own until it is connected to the structure.Source: Betonelement-Foreningen, BEF Bulletin No 6 — Montageafstivning af lodretstående betonelementer (2020)
- What determines sound insulation in the finished building?
- Not the wall alone. The Rw index describes the element as measured in a laboratory; in a building, flanking transmission through adjoining walls and floors is added, which is why alongside Rw we give R′A1, which accounts for it. The second factor is tightness: walls and floors have to be tight at surfaces, joints and service penetrations, because a single unsealed penetration can wipe out the margin the element provides. Industry guidance goes further than intuition here — elements with a mean density of 1500 kg/m³ or more need no additional surface sealing, lighter ones do; so a wall in density class D1,4 needs render, filler or a coating, while the same thickness in D2,0 does not.Source: Letbetonelementgruppen, Hæfte 3 — Lydisolering
- What are the disadvantages of precast walls?
- The biggest is the need to close the design before production. Opening layout, service routing and geometry must be settled in the shop drawings — a change after the element is cast means a new element, not a correction on site. The second is logistics: an articulated lorry needs access to the plot and the crane needs a compacted standing with reach across the whole footprint, which on tight urban plots can be decisive. The third is foundation tolerance — it must be built to the shop drawings and surveyed on handover, because a finished element cannot be eased into place the way masonry can. In return most wet trades disappear, and a stage that runs for weeks usually closes in a single erection day.
- What is the difference between a solid, a two-layer and a sandwich wall?
- A solid wall is a single monolithic load-bearing layer with no factory insulation. A two-layer wall has insulation bonded to it, while the facade is built on site. A sandwich wall contains all three layers, including a finished concrete facade. Solid walls work inside the building; the other two serve as external envelopes.
- How much does a precast solid wall cost?
- The price depends on element thickness, concrete class, the amount of reinforcement and the scope of embedded services and openings. We prepare a quotation from dimensioned floor plans and sections, usually within about a week.
- Can a solid wall be used as an external wall?
- Yes, but it needs insulation and finishing on site, because it has no factory insulation layer. If the external envelope is to arrive complete, a two-layer or sandwich wall is the right choice.
- What sound insulation does a solid wall provide?
- It depends on concrete class and thickness — the higher the surface mass of the element, the higher the Rw rating. The thickest normal-weight concrete elements reach 59,3 dB, which meets the requirements for walls between dwellings. Values for individual variants are listed in the table above.Source: Formee — technical catalogue: solid walls
- Can a solid wall act as a retaining wall?
- Yes. Properly designed and reinforced, it carries earth pressure — it is used in underground car parks, among other places. Reinforcement is specified by the structural engineer on the basis of static calculations.
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.
- Bottom edge of element
- Top edge of element
- Side edges
Documents for this product
Technical catalogue, installation manual, declaration of performance and FPC certificate — what design and handover call for.
- Technical catalogue — solid walls
Single-leaf walls: limiting dimensions 3.85 × 9.00 m, thicknesses of 100–240 mm, concrete classes LC12/13 and C20/25 or higher, a sound insulation table, connection details to the foundation slab and floor, and standard service chases.
PDF · 4 pages · 0.2 MB
- Installation manual — precast wall elements
Nine stages from documentation to finishing: transport, delivery check and storage, substrate preparation, lifting, positioning and bracing, geometry adjustment, structural connections and joints, removal of raking props, plus openings and service chases. Document in Polish.
PDF · 5 pages · 1.0 MB
- Declaration of Performance 01/26 — wall elements
Precast walls in normal-weight and lightweight concrete, classes LC12/13–C50/60. Standard EN 14992:2007+A1:2012, certificate 0761-CPR-1152.
PDF · 1 page · 0.5 MB
- FPC certificate — wall elements (EN 14992)
Certificate of conformity of the factory production control 0761-CPR-1152 for “wall elements”, issued by MPA Braunschweig (notified body 0761) under system 2+. Międzyrzecz plant, valid until 28 September 2027.
PDF · 1 page · 0.08 MB
- Guidelines for electrical installations
Cast-in services in normal-weight and lightweight concrete elements: embedding boxes and conduits, assembly on the casting table, chases and recesses for distribution boards, production tolerances, the Formee standard (Kaiser B² boxes, Ø 25 mm conduit, typical socket heights), and the required content of the layout and installation drawings.
PDF · 14 pages · 2.4 MB
- Product tolerances
Permissible dimensional and geometric deviations and surface requirements for precast elements, arranged by product standard: wall elements EN 14992, ribbed floor elements PN-EN 13224, linear elements PN-EN 13225 and others. The basis for accepting elements on site. Version 2026-02, contract annex, in force from 1 January 2026. Document in Polish.
PDF · 7 pages · 0.2 MB
- General installation conditions (OWM)
Scope of the standard installation service and additional works, performance conditions, preparation of the work front, setting out, substrate and access routes, interruptions and standstills, and acceptance. Version 2026-02, in force from 1 January 2026. Document in Polish.
PDF · 8 pages · 0.6 MB
- NORDCERT certificate — precast concrete products (EN 13369)
Certificate no. 2284 issued by Nordcert AB, Stockholm, for the factory production control of precast concrete products group B to EN 13369:2018 with supplementary Swedish requirements (Nordcert CB5). Authorises use of the BBC mark. Międzyrzecz plant, identification PO 24, valid until 31 December 2027.
PDF · 1 page · 0.6 MB
- NORDCERT certificate — ready-mixed concrete (EN 206)
Certificate no. 7316 issued by Nordcert AB, Stockholm, for the production of ready-mixed concrete to EN 206:2013+A2:2021 and DS/EN 206 DK NA:2020. Międzyrzecz plant, valid until 31 December 2027.
PDF · 1 page · 0.04 MB
- Certificate ITB-EPD 561/2023 — normal-weight concrete precast elements
Type III environmental product declaration certificate issued by the Building Research Institute (ITB) in accordance with EN 15804+A2. Issued 1 December 2023, valid for 5 years.
PDF · 1 page · 0.2 MB
- Certificate ITB-EPD 562/2023 — expanded clay concrete precast elements
Type III environmental product declaration certificate for lightweight concrete products, in accordance with EN 15804+A2. Issued 1 December 2023, valid for 5 years.
PDF · 1 page · 0.2 MB
Guides
More about this product
Articles on the decisions that precast takes before production rather than on site.
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. We deliver and install across Poland as well as in Germany, Czechia, Slovakia, Denmark and Sweden.