Underfloor Heating with Hook and Loop System in New Builds – Guide 2026

Q: What is the installation height of the Slim hook-and-loop system in new builds?

The Slim Velcro system has a total installation height starting from 26 mm: 2 mm Velcro fleece + 14 mm heating pipe (14x2 mm PE-RT) + at least 10 mm screed covering. With a 16 mm pipe, the assembly increases to 28 mm. Additionally, there is the EPS insulation (planned separately, typically 60–120 mm).

Q: Is the Klett Silent system mandatory for rental apartments?

In multi-family houses and rental apartments, DIN 4109 must be observed (L'n,w ≤ 46 dB). Klett Silent reduces impact sound by 28 dB and, in combination with a sufficiently heavy concrete ceiling, complies with the standard. For single-family homes without sound insulation requirements, Slim is sufficient.

Q: Can I operate a hook-and-loop system with an air-to-water heat pump?

Yes. The Velcro system is heat pump optimized. When designed for 35/28 °C (flow/return), an air-to-water heat pump typically achieves a COP of 3.5–4.5. The prerequisite is a well-insulated new building (KfW 55 or better) and a pipe spacing of 10 cm, which provides approx. 80–100 W/m² heating output.

Q: How fast can a hook-and-loop system be installed in a new build?

The laying speed is 20–30 m²/h for fleece and pipe. A complete residential unit of 100 m² can be laid in 4–6 hours (without screed). This is significantly faster than tacker systems (5–8 h for 100 m²) and makes the hook-and-loop system particularly economical in new builds.

Q: Which pipe spacing do you recommend for new builds with a heat pump?

Standard spacing of 10 cm (10 m/m²) with a 35 °C flow temperature provides approx. 80–100 W/m² — sufficient for well-insulated new buildings. In edge zones (floor-to-ceiling windows, exterior walls), choose 7.5 cm. For passive houses (heating load < 40 W/m²), 15 cm may be sufficient.

Q: Which flooring is suitable for a new build using a hook-and-loop system?

All common floor coverings are suitable: tiles, natural stone, parquet (thermal resistance ≤ 0.15 m²K/W), vinyl, and laminate (specifically marked as 'suitable for UFH'). Carpet is possible but reduces heating output — maximum thermal resistance of 0.10 m²K/W for carpet.

Underfloor Heating Hook-and-Loop System in New Builds: Slim & Silent Compared

The Velcro system is the ideal thin-layer system for new builds: total height from 26 mm (Slim) or 29 mm (Silent), heat pump compatible at 30–45 °C flow temperature, and the Silent Velcro system meets DIN 4109 for multi-family houses with 28 dB impact sound insulation. This guide explains system selection, installation heights, and planning requirements.

⏱ 10 min read

Structure from 26 mm

WP-compatible 30–45 °C

Planning Requirements

What you need before planning

→Shell construction accepted — substrate level and dry
→GEG-compliant thermal insulation planning is available (thickness based on U-value calculation)
→Heat load calculation according to DIN EN 12831 available
→Piping layout with heating circuit distribution agreed upon (max. 100 m/circuit)
→For multi-family houses/rental apartments: Sound insulation certificate according to DIN 4109 required
→Heat pump: Flow temperature design planned for 30–45 °C

Hook and Loop Slim & Silent at a Glance

The hook-and-loop system comes in two versions, differing in installation height and sound insulation requirements: Slim (2 mm) is the standard version for single-family homes and commercial properties without sound insulation requirements. Silent (5 mm) is the right choice for multi-family homes and rental apartments, as it offers 28 dB impact sound insulation and thus helps to comply with DIN 4109. Both versions are installed identically — the pipe is pressed into the hook-and-loop fleece without tools — and can be combined with all common floor coverings.

Planning in New Construction: 5 Core Topics

System Choice: Slim or Silent?: When building a new house, the question is: Hook-and-loop system Slim (2 mm) or Silent (5 mm)? Slim is suitable for single-family homes without sound insulation requirements and minimizes the floor structure to a total height of 26–28 mm (2 mm fleece + 14 mm pipe + 10 mm screed). Silent (5 mm) supplements the insulation effect with 28 dB impact sound reduction and is mandatory in multi-family homes that must comply with DIN 4109. Total structure with Silent: 29–31 mm.

Precise planning of overall heights: The thin-layer system with hook-and-loop fasteners is one of the shallowest on the market: with Slim from 26 mm, with Silent from 29 mm (without EPS insulation boards). The EPS insulation boards are placed underneath and are planned separately in terms of build-up height (typically 60–120 mm depending on GEG requirements). Door heights, stair landings, and transitions to existing floors must be considered early in the shell construction plan. Rule of thumb: For every 10 mm less build-up = doors can be planned 1 cm shorter.

Screed cover and expansion joints: Minimum screed cover over heating pipe: 10 mm. Recommended total build-up of leveling compound/screed: 25–30 mm. Larger areas over 40 m² must be divided into sections (expansion joints at door openings, room corners, and transitions). The heating protocol according to DIN EN 1264-4 is mandatory in new builds for warranty purposes. Anhydrite screed cools down faster than cement screed – an advantage with heat pumps.

Heat Pump: Optimizing System Temperatures: Hook-and-loop system is fully heat pump compatible. Recommended design temperature: 35/28 °C (flow/return) for modern heat pumps (COP > 4). For well-insulated new builds (KfW 55 or better), a flow temperature of 30–35 °C is sufficient. A pipe spacing of 10 cm (10 m/m²) provides a heating output of approx. 80–100 W/m² at 35 °C flow temperature — sufficient for new builds with a heat load of < 80 W/m².

Multi-family house: Sound insulation with Silent hook-and-loop system: In multi-family homes, DIN 4109 stipulates an impact sound insulation of at least 46 dB (weighted normalized impact sound pressure level L'n,w). The Klett system Silent reduces impact sound by 28 dB (Delta Lw), which, in combination with an 18 cm raw concrete ceiling, meets these requirements. For rental apartments, sound insulation verification is recommended before construction begins. MC Therm provides technical data sheets for verification upon request.

Frequent questions about the hook-and-loop system in new builds

The Slim Velcro system has a total installation height starting from 26 mm: 2 mm Velcro fleece + 14 mm heating pipe (14x2 mm PE-RT) + at least 10 mm screed covering. With a 16 mm pipe, the assembly increases to 28 mm. Additionally, there is the EPS insulation (planned separately, typically 60–120 mm).

In multi-family houses and rental apartments, DIN 4109 must be observed (L'n,w ≤ 46 dB). Klett Silent reduces impact sound by 28 dB and, in combination with a sufficiently heavy concrete ceiling, complies with the standard. For single-family homes without sound insulation requirements, Slim is sufficient.

Yes. The Velcro system is heat pump optimized. When designed for 35/28 °C (flow/return), an air-to-water heat pump typically achieves a COP of 3.5–4.5. The prerequisite is a well-insulated new building (KfW 55 or better) and a pipe spacing of 10 cm, which provides approx. 80–100 W/m² heating output.

The laying speed is 20–30 m²/h for fleece and pipe. A complete residential unit of 100 m² can be laid in 4–6 hours (without screed). This is significantly faster than tacker systems (5–8 h for 100 m²) and makes the hook-and-loop system particularly economical in new builds.

Standard spacing of 10 cm (10 m/m²) with a 35 °C flow temperature provides approx. 80–100 W/m² — sufficient for well-insulated new buildings. In edge zones (floor-to-ceiling windows, exterior walls), choose 7.5 cm. For passive houses (heating load < 40 W/m²), 15 cm may be sufficient.

All common floor coverings are suitable: tiles, natural stone, parquet (thermal resistance ≤ 0.15 m²K/W), vinyl, and laminate (specifically marked as 'suitable for UFH'). Carpet is possible but reduces heating output — maximum thermal resistance of 0.10 m²K/W for carpet.