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How To Heat A House Cheap! A Look At On Demand Radiant Floor Heat

If you are looking for an incredible way to heat your house, garage, barn or outbuilding on the cheap – today’s article about on demand radiant floor heat is right up your alley. Especially if you happen to be building or remodeling in the near future!

We had our first experience with an on demand radiant floor heat system when we built our original farmhouse back in 2016. Knowing we were building on a concrete slab, our foundation contractor suggested we look into floor heat.

We had already planned on using an on demand tankless water heating system in the house. We loved the thought and savings of not having to heat a water tank 24/7. Even better, we really loved never having to worry about running out of hot water in the shower!

on demand radiant floor heat - original farm house
We used on demand floor heat to heat our entire farm house at the old farm. It allowed us to heat it comfortably, inexpensively, and without having to have any registers, vents or duct work. We loved it so much, we are using the same system in our new farm house this year.

But what we didn’t know at the time was that we could use the same tankless on demand system to heat our floors and house too. That meant we could not only eliminate the need for a hot water tank, but an expensive furnace for our house. And did that ever pay off with the budget – and for lowering our future heating bills!

The Simplicity Of An On Demand Radiant Floor Heating System

An on-demand radiant floor heating system is amazingly uncomplicated. You can install it into a concrete pad, or underneath an existing tile, laminate, stone, wood or even carpeted floor.

We installed our system directly into the concrete slab as it was being poured. By far, this method is the easiest and least expensive option of all. Of course, with this method, it does have to be new construction or a major remodel. There are, however, other options to install floor heat in existing structures as well.

The Benefits of On Demand – How To Heat A House Cheap!

For us, the system was truly love at first warmth! Not only for the amazing way it heated our entire house, but also for just how efficiently it did so. In fact, so efficiently that in the four winters we spent in the house, our winter gas bill averaged $100 a month!

how to heat a house cheap
Before pouring our concrete slab, insulation panels and plastic pex tubing was first laid out within the frame. Then, concrete was poured over top to complete the floor.

That figure becomes even more amazing when you consider that not only did we heat our entire home with gas, but also used it to heat all of our hot water, and to power our home’s gas stove!

But it was the warming qualities of the floor we loved most. There is nothing quite like stepping out of bed on a cold winter night and having your feet feeling warmth from below. And even better, no drafty vents blowing air into your face.

But as you will see below, the advantages don’t stop there. Here is a look at installing an on-demand radiant floor system, and why it can save you thousands on heating bills, and your construction costs too!

How On Demand Radiant Floor Heat Works – And How It Can Heat A House Cheap!

There are many types of radiant floor heat, and they all certainly can heat a space efficiently. But an on demand radiant floor system takes those efficiencies to the next level.

barndominium floor heat
Pouring the floors of the barndominium. The heat tubes are first rolled out on top of insulation panels. Next, the concrete goes in on top, and the floor is complete with heat!

The heating system is designed around a central unit that heats the water as needed, and only when needed. Instead of having a boiler or hot water tank that keeps a reserve of warm water, the water flows through the central unit for hot water on demand.

The system can run on propane or natural gas, and the heating jets only fire when hot water is requested. This is where the savings really happen. No need for constantly heating a tank of water that is sitting idle.

How It Works

To activate the floor heat, you simply turn the thermostat up, and it begins to slowly heat the floor. It does this by circulating the hot water through the tubes which then radiates the heat upward into the room.

We all know that heat rises, so by having the heat starting at the lowest point, the system already has an advantage. Once the floor is warm, the water circulates through, only heating when the thermostat falls below the range set.

navien unit
For our on demand system, we use a combination unit from Navien.

Unlike a traditional furnace, a radiant floor heat system is constant. The heat is always coming up. When a door opens or a window opens, hot air exits, but more radiates up quickly. For us, it was so nice not to hear the furnace kick on as soon as cold air entered a space.

We turn our system on in early fall as it begins to get cold, and it stays on until mid spring as it warms. It only heats when needed, and without the worry of using tons of fuel. Best of all, no changing furnace filters, and no worrying about that furnace kicking on to blow dust everywhere!

How To Install – How To Heat A House Cheap!

Before a slab is poured, a looping pattern of plastic tubing (pex tubing) is laid on foam insulating sheets and the tubes are then secured with large staples. Next, the concrete is poured on top. In essence, the tubing becomes the duct work of the system.

Once the house framing is complete, the tubes are then connected to a wall-mounted, on-demand gas-fired water heater. Not only does the system act as our furnace, but it is also our hot water provider too. The lines to the showers, sinks, and anywhere we need hot water come out from a separate baffle within the unit.

on demand radiant floor heat - how to heat a house cheap
It may look like a mess, but these are the tubes that have been run through the concrete floor at our new building site. Another nice feature of the system is that it can have zones for various rooms. This allows you to save even more by turning down areas that don‘t need as much warmth.

Again, even a boiler or hot water floor system is efficient for heating the tubes and the floor. But by using an on demand system, we eliminate any need for a tank at all. Both for the floor, and for our hot water needs in the house.

We chose a Navien unit for our first tankless system, and will be installing the same in the new barndominium. The heating unit measures 28″ x 20″, and takes up much less space than a hot water tank, let alone an entire furnace. It also happens to be extremely quiet when in operation.

As for cost, the tubing and on demand system together were less than we would have paid for a single budget furnace unit. Let alone having to buy and install HVAC, a hot water heater and more! See: Barndominium Project

Final Features – How To Heat A House Cheap!

You could certainly tile or carpet over a concrete floor. But to save even more on our building cost, we turned the concrete slab for our home into our final floor with a few simple steps.

on demand radiant floor heat - how to heat a house cheap
The new concrete floor with its tile like cuts. Once the framing is all complete, we will then acid stain the floor to look like marble. It creates a low-cost finished floor that looks great, and saves on the budget.

For starters, we had the concrete slab scored into 3 x 3′ “tiles” with saw cuts. This not only helps to eliminate the worry for cracks forming on the floor, but also gives a unique tile look to the floor. Next, to really bring out that tile look, we acid stain the concrete for a marbled look.

We loved the look so much in our old farmhouse, we are doing the exact same process in the new barndominium. Not only does it save big budget dollars on flooring, it also looks great and hold up exceptionally well.

Here is to the amazing efficiency of on demand radiant floor heat. And, to heating your house on the cheap! Jim and Mary.

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