When it comes to choosing a type of underfloor heating system for your home, two of the most popular options are electric and water (hydronic) systems. Both offer efficient and comfortable ways to heat your floors, but they differ in how they work and their operating costs. Knowing the pros and cons of each can help you decide which is the more budget-friendly choice for your needs.
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How Electric Underfloor Heating Works
Electric underfloor heating consists of electric wires or mats that are installed beneath the floor. As electricity passes through the wires, they heat up and gently warm the floor above.
There are two main types of electric systems:
Electric Wire Systems
Electric wire systems involve installing separate wires in a pattern across the subfloor. The wires are held in place with clips and are covered with a self-leveling concrete before laying the finished floor. The wires are connected to a thermostat which controls the temperature.
Electric Mat Systems
Electric mats provide full coverage heating with wires woven into a flexible mesh mat. The mats come in different sizes and shapes to fit the area. They are simply unrolled into place on the subfloor and covered with concrete or the finished flooring. Like wire systems, mats are controlled by a thermostat.
Some key advantages of electric underfloor heating include:
– Individual room control – Each room can have its own thermostat for personalized heating.
– Lower installation cost – Electric systems require less labor and material costs to install compared to water.
– Faster response time – Electric mats and wires heat up and cool down faster than water-based systems.
– No ongoing maintenance – Electric systems have fewer mechanical parts so require less maintenance.
How Water Underfloor Heating Works
Water underfloor heating, also known as hydronic radiant floor heating, uses hot water flowing through tubes or pipes laid beneath the floor. The pipes are connected to a boiler or water heater which heats the water and pumps it through the closed loop system. As the hot water moves through the pipes, it gently warms the floor above.
There are two main types of water underfloor configurations:
Water Pipe Systems
This involves installing numerous small diameter plastic pipes in loops or coils across the subfloor. The pipes are attached to a manifold which controls the water flow. They are then covered in concrete or the finished floor.
Water Tubing Systems
This uses flexible polyethylene tubing in a pattern under the floor. The tubing is often prespaced in mats or fixed to panels for easier installation. The mats or panels simply unroll or click into place. The tubing connects back to the manifold supplying the hot water.
Benefits of water underfloor heating include:
– Even heating – Hot water can heat a floor evenly and efficiently.
– Whole home heating – Water systems can heat an entire home, while electric is often limited to certain rooms.
– Long-term comfort – Water maintains stable temperatures.
– Cost-effective – Water heat is often less expensive compared to electric.
– Environmentally friendly – Water systems pair well with renewable heating sources.
Operating Costs Comparison
One of the biggest factors when choosing between electric and water underfloor heating is the operating and energy costs. Let’s compare:
Electric Underfloor Heating Running Costs
The running costs of electric systems depends on:
– Electricity rate per kWh in your location
– Size of the area being heated
– Hours of use
– Outside temperature conditions
Most electric mats use between 10-15 watts per square foot. With the average US electricity rate around 13 cents/kWh, it would cost around 13-19 cents per square foot annually to run an electric mat.
So heating a 20 sq ft bathroom 8 hours a day all year would cost:
20 sq ft x 15 watts x 8 hours x 365 days = 350 kWh
350 kWh x $0.13 per kWh = $45.50 per year
This equates to around $2.28 per square foot annually.
Water Underfloor Heating Running Costs
For water-based systems, costs will vary based on:
– Energy source – Natural gas, oil, electricity, solar, etc.
– Boiler efficiency rating
– Location and pumps required
– Pipe layout
– Hours of use
– Outside temperature
Typically, water underfloor uses between 10-20 BTU per square foot per hour. With natural gas prices around $1.50 per therm in the US and 10 BTUs equaling 1 therm, the annual cost would be $1.50 to $3 per square foot.
Using the same 20 sq ft bathroom example for 8 hours daily, that would equate to:
20 sq ft x 15 BTU x 8 hours x 365 days = 876,000 BTU
876,000 BTU / 10 = 87.6 therms
87.6 therms x $1.50 per therm = $131.40 per year
Which is around $6.57 per square foot annually.
So for the same room usage, water underfloor heating would have operating costs approximately 3 times higher than electric.
Installation Cost Comparison
Installation prices can also impact the overall budgets between electric and water underfloor heating. Here is an overview of typical installation costs:
Electric Underfloor Heating Installation
– Electric mats – $6-$12 per square foot installed
– Electric wire systems – $8-$15 per square foot installed
The installation process is relatively straightforward and does not require specialized tradespeople. This helps keep labor costs lower. Total installation prices vary based on:
– System chosen – Mats are generally cheaper than custom wire layouts
– Flooring type – Tile is more labor intensive than laminate or engineered wood
– Size of project – Larger areas are more affordable per square foot
– Additional costs – Any special structural work or repairs add expenses
Water Underfloor Heating Installation
– Hydronic systems – $10-$30 per square foot installed
The installation for water-based heating is more complex and typically requires professional installation. Cost factors include:
– Scope of project – Whole home systems are more expensive than a single room
– Materials needed – Pipes, manifolds, thermostats, and pumps
– Concrete work – New slab pours increase costs over using existing subfloors
– Labor rates in your area
– Any repairs or service upgrades required – Like improving electrical panels or plumbing
| System Type | Installation Cost per Sq Ft |
|---|---|
| Electric Mats | $6 – $12 |
| Electric Wire | $8 – $15 |
| Water Underfloor | $10 – $30 |
As shown, electric underfloor heating can often be installed for 50% less than water-based systems.
Environmental Impact
Eco-friendliness is another consideration when comparing electric and water underfloor heating.
Electric Underfloor Heating Environmental Impact
Electric systems are only as clean as their power source. If your electricity comes from fossil fuels like coal, then heating with electric mats and wires generates pollution.
However, in areas with high renewable energy usage, electric heat can be low emissions. Pairing electric radiant flooring with solar panels or a wind turbine can make the system carbon neutral.
Electric underfloor only heats as needed, avoiding energy waste. But electricity rates are often higher during peak cold weather when heating demand is high.
Water Underfloor Heating Environmental Impact
Water-based heating is more efficient and uses less energy compared to electric. This results in lower carbon emissions.
The system can also utilize greener heat sources. Pairing hydronic radiant flooring with a high-efficiency gas boiler, solar water heating, or geothermal heat pump reduces environmental impacts.
Water maintains comfortable temperatures using less energy than electric options. This conserves natural resources and reduces pollution.
Comfort Factor
Underfloor heating comfort depends on the type of system:
Electric Underfloor Heating Comfort
Electric mats and wires emit a gentle warmth directly from the floor. This leaves the rest of the room cooler.
The radiant heat feels comfortable underfoot but does not heat the surrounding air. Rooms may feel drafty or require additional heating sources for sufficient warmth.
Temperatures can fluctuate with electric systems. Turning up the thermostat causes floors to quickly heat up. But they also cool down sooner once heating is turned off.
Water Underfloor Heating Comfort
Hydronic systems provide an enveloping warmth. As water pipes heat the floors, they also gently warm the room’s air.
This offers steady, even comfort throughout the space. The mild radiant heat from below combats cold air sinking from windows or doors.
Water also maintains consistent comfortable temperatures. Adjustments heat or cool the dense concrete slab gradually over hours instead of instantly like electric systems.
Maintenance Requirements
Underfloor heating systems have minimal maintenance needs but require some care and inspection:
Electric Underfloor Heating Maintenance
– Keep floors clean – Dirt and debris can insulate wires and reduce efficiency. Periodic cleaning is recommended.
– Check connections – Inspect wires and thermostats for damage. Repair as needed.
– Test heating – Turn on periodically to ensure the system is functioning properly.
– Consider control upgrades – New smart thermostats can optimize electric heating efficiency.
Water Underfloor Heating Maintenance
– Flush piping – Annual flushing removes mineral deposits from pipes.
– Check tubing – Inspect tubing and connections for leaks or damage.
– Bleed air – Occasional air bleeding removes trapped air.
– Monitor boiler – Arrange annual service for optimal performance.
– Inspect pumps – Check pump operation and replace worn components.
– Control updates – Consider new thermostats or zone control systems.
Properly installed electric and water underfloor systems can last 20-50 years with minimal maintenance. Following recommended care and inspections prolongs the life expectancy.
Conclusion
When choosing between electric and water underfloor heating, there are several factors to weigh like:
– **Operating costs** – Electric systems have lower energy bills in most cases.
– **Installation price** – Electric options are 50% cheaper to install on average.
– **Environmental benefits** – Water heating is often greener, especially when using renewable energy sources.
– **Comfort** – Water provides steady warmth, while electric heat fluctuates faster.
– **Maintenance** – Both have minimal maintenance, mainly preventative inspections.
Ultimately, electric underfloor heating is usually more budget friendly for smaller projects like bathrooms or laundry rooms. The lower install costs and electricity rates keep expenses down.
Water-based systems better suit whole home heating for their efficiency and comfort benefits. While installation is pricier, longer-term energy savings can pay off. Water also pairs well with eco-friendly boiler upgrades.
Carefully consider your budget, usage requirements, and environmental goals. This will help determine if electric or water underfloor heating is the more cost-effective choice for your home heating needs.