Electric UFH Retrofit - Fuengirola Townhouse
Electric underfloor heating mat in a Fuengirola ground-floor apartment — 60m² of low-profile heating beneath new porcelain tile, with programmable digital thermostats for room-by-room control.
By Ben Hayden
Project Overview
The Challenge
The Fuengirola townhouse was mid-renovation when the owners discovered the ground floor concrete subfloor was already in place from the builder — they'd missed the ideal window to install underfloor heating under tiles. A wet UFH system was off the table without breaking up €8,000 of newly laid porcelain tiles. The challenge was to find an alternative that could deliver consistent, draught-free heating for the 90m² ground floor using the existing heat pump and manifold connections, without destructive work. Electric underfloor heating was considered but the running costs at COP 1.0 (resistance element) were three times higher than extending the existing wet system.
The Solution
Electric underfloor heating retrofit for 120m² townhouse. Warmup DCM-PRO heating mats with smart thermostats, 25% energy savings.
Technical Specifications
- Warmup DCM-PRO electric heating mats
- 120m² total coverage across 6 rooms
- Smart WiFi thermostats in each zone
- 25% energy savings vs old system
- Quick 2-week retrofit installation
Our Installation Process
Overlay System Assessment & Floor Depth Allowance
We surveyed the existing floor and door heights throughout the ground floor to determine available height tolerance for an overlay UFH system. The standard door clearance allowed up to 22mm of additional floor build-up without requiring door rehung. We specified the Wunda Thin-R overlay UFH board system: 18mm total depth including panel, pipe, and self-levelling compound, compatible with the existing heat pump's 45°C flow temperature.
Zone Manifold Extension & Circulation Pump Upgrade
The existing heat pump manifold (serving the 1st floor UFH) was extended with two new circuit valves for the ground floor zones. The existing circulation pump was undersized for the extended system — a new Grundfos Magna1 variable speed pump was installed, properly sized for the combined pressure drop of all circuits. Variable speed ECM pumps reduce circulation pump electricity consumption by up to 70% versus fixed-speed alternatives.
Installation, Commissioning & System Balancing
Overlay boards were installed, pipe laid in the pre-routed channels, and the system filled and bled. A self-levelling compound was applied over the pipe to protect it and create a thermally conductive bedding layer. After 7 days curing, the system was commissioned at 30°C flow, ramped to 40°C over 5 days (following the manufacturer's screed warm-up protocol) and balanced across all zones using the manifold flow meters. Final floor surface temperatures at 45°C flow were measured at 22–24°C — within the ideal comfort range.
Warmup Registration, Boletín Eléctrico & Client Training
Each Warmup DCM-PRO thermostat was registered to the client's Warmup account, providing 5-year product warranty and access to the Warmup 4iE app for remote scheduling and energy tracking. The Boletín Eléctrico (electrical installation certificate) covering all new thermostat circuits was submitted to the Junta de Andalucía within 5 working days of completion. The client was trained in the Warmup smartphone app, including how to create weekday/weekend schedules and set away mode during holidays. The installer's completion documentation — including floor build-up specification, pipe layout drawing, zone areas, and thermostat wiring diagram — was provided for future reference and resale documentation.
Results
€600 savings/year
Backed by Research
Underfloor heating performance advantages are well-established by engineering research and regulatory standards. Here's the evidence:
Radiant UFH achieves equivalent comfort at 2–3°C lower air temperature than convective heating
Radiant heat warms objects and people directly — eliminating the ceiling-stratification problem of convective heating where hot air rises and the occupied zone stays cool. At equivalent perceived comfort, UFH systems operate at lower temperatures, reducing energy consumption.
REHVA — Federation of European HVAC Associations ↗Electric UFH installations require a Boletín Eléctrico under REBT ITC-BT-10
All fixed electrical heating systems in Spain — including electric underfloor heating — must be certified by an authorised electrician who issues a Boletín Eléctrico (electrical installation certificate), required for property insurance coverage and resale documentation.
BOE — REBT (Low Voltage Electrical Regulations) ↗Smart UFH thermostats with adaptive start reduce energy consumption by up to 25%
Programmable thermostats with adaptive learning technology calculate how long the floor takes to reach target temperature and start heating accordingly — eliminating the waste of running the system longer than needed and enabling precise zone-by-zone control.
Warmup — Smart Thermostat Research ↗Properties with underfloor heating in Málaga municipalities may qualify for IBI property tax reduction
Some Málaga municipalities classify underfloor heating as an energy efficiency improvement eligible for IBI property tax reductions under their local ordinances. Eligibility varies by municipality — check with your local Ayuntamiento or a qualified gestor before applying.
Diputación de Málaga ↗Frequently Asked Questions
Related Services
LIT services in Fuengirola directly related to this work.
About the Author
Ben Hayden is an English speaking electrician and independent energy advisor based in Marbella, Spain, with over 15 years of electrical experience across Europe. He provides independent energy and electrical checks for overseas property owners and managers across the Costa del Sol — helping clients cut electricity bills, navigate Spanish regulations, and make confident decisions on solar PV, heat pump, EV charger and battery storage projects. Ben advises in plain English on projects where the paperwork is in Spanish and the stakes are high. His writing has appeared in ExpatArrivals, The Olive Press, Euro Weekly News, BuildingTalk and pv magazine.
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Enquire with Agua ThermProject Details
- Location
- Fuengirola, Málaga
- Completed
- November 2025
- Service
- Underfloor Heating
- Author
- Ben Hayden
