Render & ETICS Facades
A rendered facade combines insulation and aesthetics in a single system. Learn about ETICS (External Thermal Insulation Composite Systems), material selection, reinforcement mesh and consumption calculations to European standard EAD 040083.
Render systems — comparison
| System | Binder | Base coat use | Finish coat use | Advantages |
|---|---|---|---|---|
| Mineral-based | Cement / lime | 5–8 kg/m² | 2.5–3.5 kg/m² | Vapour-open, non-combustible |
| Acrylic-based | Acrylate | 6–7 kg/m² | 2.0–3.0 kg/m² | Flexible, many textures |
| Silicone-based | Siloxane | 6–7 kg/m² | 2.0–2.5 kg/m² | Hydrophobic, self-cleaning |
ETICS build-up — cross section
From existing wall outward:
Reinforcement mesh — technical requirements
- Material:Alkali-resistant glass fibre (AR-glass)
- Weight:Minimum 145 g/m² (standard); 160 g/m² in wind-exposed locations
- Overlap:Minimum 100 mm in all directions
- Extra reinforcement:200 mm diagonal strips at all corners and openings (window angles)
- Position in base coat:At least 2/3 of the thickness from the outer face — fully embedded
- Mesh type:System-certified only — foil mesh is not acceptable
Step-by-step — ETICS installation
The substrate must be stable, dry and clean. Remove loose render, salt efflorescence and organic growth. Prime absorbent surfaces with a bonding primer.
Do not work below 5°C or above 30°C, in direct sunlight, or when wind exceeds 6 m/s.
Apply system adhesive using dots-and-perimeter method (minimum 40% coverage) or full-coverage technique. Fix boards in a brick-bond pattern — no continuous vertical joints.
Drive 6 mechanical fixings/m² (disc anchors) once adhesive has cured (24–48 h). Also fix perimeter with at least 2 fixings per linear metre at edges.
Apply base coat with a steel float to approximately 3–4 mm. Immediately press in the glass-fibre mesh so it is fully embedded. Work top-down to avoid run marks.
Total thickness including embedded mesh: 4–6 mm. Allow to cure at least 3 days.
Apply system-certified primer by roller or brush. Allow to dry per data sheet (normally 2–12 hours). Primer ensures adhesion and evens porosity.
Apply finish coat (1.5–3.0 mm for fine plaster; 2.5–5 mm for heavier textures) with a steel float. Work the desired texture with a plastic or wooden float within the open time (typically 15–30 min).
Always work across a full scaffold-level lift without stopping — joints will show.
Consumption table
| Component | Low | Medium | High |
|---|---|---|---|
| Base coat | 5 kg/m² | 6.5 kg/m² | 8 kg/m² |
| Finish coat | 2.0 kg/m² | 2.8 kg/m² | 3.5 kg/m² |
| Primer | 0.1 l/m² | 0.15 l/m² | 0.2 l/m² |
| Mesh (incl. overlap) | 1.1 m²/m² | 1.2 m²/m² | 1.3 m²/m² |
| Adhesive | 3 kg/m² | 4 kg/m² | 6 kg/m² |
Regulatory requirements
Common mistakes
- ✗Working in direct sunlight — base coat dries too fast and cracks
- ✗Base coat too thin — mesh not fully embedded, corrodes over time
- ✗Aligned insulation board joints — thermal bridges and risk of render cracking
- ✗Gaps between boards wider than 2 mm — fill with PU foam, not render
- ✗Mixing components from different system suppliers — system warranty is void and product performance uncertain
- ✗Missing diagonal mesh at window/door corners — cracks within months
Calculate render and ETICS
Use the calculator to estimate kg base coat, finish coat, mesh and primer quantities.
Open render calculator →Frequently asked questions
What is ETICS and is it code-compliant?
ETICS (External Thermal Insulation Composite System) is a CE-marked facade system for exterior insulation with render finish. Systems are approved to EAD 040083 and CE-marked by manufacturers. Widely used across Europe and increasingly in North America as EIFS.
How much base coat render do I need per m²?
Mineral base coat: 5–8 kg/m² (depending on substrate flatness). Acrylic and silicone systems: 6–7 kg/m². Finish coat (thin-coat): 2.0–3.5 kg/m² depending on texture. Always check manufacturer data sheets.
What reinforcing mesh is required in ETICS render?
Alkali-resistant (AR) glass fibre mesh, minimum 145 g/m², fully embedded in the base coat. Overlap joints by at least 4" (100 mm). Add 200 mm diagonal strips at all window and door corners.
References
- → Weber — render and ETICS system installation guides
- → Mapei — render and plaster product technical data sheets
- → Dryvit / Sto — EIFS/ETICS technical information and application guides
- → Render system manufacturer datasheets — coverage rates depend on substrate profile and layer thickness; always verify with your specific product
Material quantities are indicative. Actual kg/m² depends on substrate roughness, layer count and application method. Last reviewed: May 2026