You’ve experienced radiant floor heating and decided, “I need this in my bathroom!” The problem is, you don’t want to rip up your existing floor for a heated tile floor, or you’re not ready to remodel the bathroom. With retrofit mats, there’s no need to do any of that! Your carpet, tile, wood or stone can stay right where it is. Instead, retrofit mats attach to the subfloor in the joist bays of your existing floors to warm any floor type.
It’s best for anywhere the joists can be easily accessed, such as a garage ceiling or from your basement or crawl space.
What Does it Mean to Retrofit Radiant Floor Heating?
Retrofit is the process of adding radiant floor heating to an existing building or home. This innovative heating solution is gaining popularity among homeowners looking to upgrade their heating systems without the need for major renovations. With retrofit radiant floor heating, you can enjoy the cozy warmth of heated floors in any room.
Installing retrofit radiant floor heating involves minimal disruption to your existing space, making it a convenient option for those looking to enhance their comfort levels. Unlike traditional forced-air systems that rely on ductwork, retrofit radiant floor heating uses a network of electric heating elements placed beneath the floor surface to evenly distribute heat throughout the room.
Why Use Retrofit Mats vs Other Radiant Heating?
For homeowners who want the comfort of heated floors, but don’t want to deal with the hassle or expense of replacing their existing flooring, retrofit radiant floor heating systems are becoming an increasingly popular solution. Traditional electric floor heating systems are typically installed on top of the subfloor and beneath the finished floor, which makes them a good choice for new construction or major remodels. Retrofit mat systems, on the other hand, take a different approach. These mats are installed between the floor joists beneath the subfloor, allowing radiant heat to be added from below.
This installation method offers several advantages over traditional in-floor heating systems, the biggest of which is that your existing wood, tile, laminate, luxury vinyl, carpet, or stone flooring can often remain in place. By allowing you to keep your existing flooring, the need for demolition is eliminated, and the disruption that the installation causes is greatly reduced. This means that for homeowners who want the benefits of heated flooring, but don’t want to do a full renovation, retrofit systems are an excellent choice.
While traditional floor heating installation methods are often the go-to option during a major floor replacement, large renovation, or new construction project, retrofit systems offer the unique opportunity to add radiant heat to existing spaces that otherwise wouldn’t be ideal candidates for floor warming. Retrofit floor heating installation is a practical solution for room additions, bathroom upgrades, and older homes that have accessible crawlspaces or unfinished basements.
What Flooring Works With Retrofit Heating?
Because retrofit radiant heating systems are installed beneath the subfloor, they can be used with many common flooring materials without removing the finished floor.
Retrofit systems are frequently installed under:
- Tile
- Stone
- Engineered hardwood
- Laminate flooring
- Luxury vinyl plank (LVP)
- Carpet (with appropriate carpet and pad specifications)
The warmth travels through the subfloor and flooring material to provide comfortable floor temperatures above, and some flooring materials transfer this heat more efficiently than others.
Tile and stone typically provide the fastest heat transfer, while engineered wood, laminate, and luxury vinyl also perform well when installed within the manufacturer’s temperature recommendations. Carpet can be heated as well, although thicker carpet and padding may reduce overall heat transfer.
Is Your Home a Good Candidate for Retrofit Floor Heating?
Not every home is an ideal candidate for retrofit floor heating. Because the heating mats are installed between the floor joists, installers need access to the joist bays during installation.
This means that retrofit radiant floor heating works best in situations where installers can easily access the joist bays without disturbing the finished flooring above, including:
- Homes with unfinished basements
- Crawlspace foundations
- Bathrooms above unfinished garages
- Room additions with exposed framing
- Other areas where the ceiling below is already open or can be temporarily opened
Retrofit systems are not recommended for upper floors when a finished living space is directly below. Installation in these areas often requires that portions of the ceiling be removed for installation and later replaced, increasing the project’s cost and disruption.
If you’re unsure whether your home is a good candidate, our team can review your project and help determine whether retrofitting radiant floor heating is the right solution.
Installation Process for Retrofitting Radiant Floor Heating
Starting the process of adding radiant floor heating to your home can be exciting. However, it’s important to understand the necessary steps to ensure a smooth installation process.
Beginning with a clear roadmap of the installation process is important for retrofit projects. The steps include:
- Assessment: Conducting a thorough evaluation of your existing flooring structure to ensure compatibility with radiant heating. Always check the manufacturer guidelines before purchasing or installing radiant floor heating.
- Planning: Creating a detailed plan and layout for the heating elements, considering the rooms and zones to be heated.
- Joist Work: Gaining access to the joists from below the floor and preparing them for the installation of the heating system.
- Heating Element Installation: Laying down the electric radiant heat mats or cables according to the plan.
- Electrical Connections: Connecting the heating system to the power supply and installing thermostats.
- System Testing: Testing the thermostat and heating system to ensure everything operates correctly.
- Insulation Placement: Applying insulation to maximize heat distribution upwards into the rooms is essential. A minimum of R-19 and a maximum of R-11 Fiberglass insulation is required directly under and against the joist mats (cannot be spray foam insulation).
The Role of Joists and Insulation
Floor joists play a central role in the retrofit process. This approach typically involves attaching heating elements directly to the underside of the subfloor between the joists. Insulation is then subsequently added beneath the heating elements to minimize heat loss downwards and direct the warmth upwards into the living space. Insulation is an essential part of the installation process.
Best Practices for Ensuring Efficient Heat Distribution
An effective retrofit not only lies in installation precision but also in optimizing heat distribution. Strategic positioning of the heating elements and comprehensive insulation are crucial. Here are some best practices:
- Avoid Obstructions: Keep heating elements clear from obstructive objects like furniture to promote the even spread of warmth.
- Thermal Mass: Consider the thermal properties of your flooring material; denser materials retain heat longer, aiding in efficient distribution.
- Reflective Layers: Utilize reflective barriers beneath the heating elements to efficiently direct the heat upwards.
- Consistent Testing: Perform regular tests during installation to detect any problems early on, ensuring the heat flows smoothly across the entirety of the floor.
Find Your Retrofit Radiant Floor Heating at Warm Your Floor Today
Retrofit radiant floor heating allows you to enjoy the comfort of warm floors without the expense and disruption of removing your existing flooring. Whether you’re upgrading your bathroom, renovating your kitchen, or adding comfort to an older home, retrofit systems offer a practical solution for bringing radiant heat to spaces that may not be candidates for floor heating otherwise.
Warm Your Floor is an authorized dealer of trusted retrofit radiant heating systems, including SunTouch UnderFloor mats, and our team has years of experience helping homeowners and contractors design systems for existing homes. If you’re unsure whether your project is a good fit or need help selecting the right products, contact our experts or request a quote today. We’ll help you design a retrofit radiant heating solution tailored to your home and comfort goals.
Stay Warm and Informed
Stay one step ahead with expert articles, heating hacks, and product news delivered right to your inbox when you sign up for our newsletter.
Retrofit Floor Heating FAQs
Will Retrofit Floor Heating Heat the Entire Room?
Retrofit floor heating is primarily designed to warm the floor surface and improve comfort. In smaller, well-insulated rooms it may provide much of the room’s heat, but in larger spaces it is generally considered a supplemental heating system.
How Do I Connect the Heating Mats to the Thermostat?
The thermostat will be mounted in the room you are heating and all power leads from each mat will run to a junction box, then you’ll use Romex to reach the thermostat location.
Can Retrofit Heating Be Installed Between Floors?
In most cases, no. Retrofit mat systems require access to the joist bays from below, making them best suited for homes with unfinished basements, crawlspaces, or garages beneath the heated room.
Can I Install Retrofit Heating Myself?
Many homeowners install the retrofit heating mats and insulation themselves as a DIY project. However, the final electrical connections should always be completed by a qualified electrician.
Will Retrofit Floor Heating Heat the Room or Just the Floor?
Retrofit systems warm both the floor and the room above it, but their primary purpose is improving floor comfort. Overall room heating performance depends on the size of the space, insulation, flooring material, and climate.
Can I Install Retrofit Heating if Pipes and Wires Are in the Joist Bays?
Possibly, as long as there is enough open space to install the mats and insulation safely. The heating mats should not come into contact with plumbing, electrical wiring, or HVAC components.
Is Insulation Required?
Yes. Insulation installed beneath the heating mats is essential because it directs heat upward into the room and significantly improves system performance and efficiency.
Phillip says:
Just want to clarify, an earlier response says this can’t be installed between house levels, but we have a bathroom directly over a finished (but uninsulated) garage, would we be able to install this under the bathroom (we can remove the drywall and reinstall)? I’m not seeing a reason why not but just want to check.
Floor Heat Expert says:
You can install SunTouch UnderFloor retrofit mats as you have described; you can remove the drywall, install UnderFloor, insulate and reinstall drywall. Don’t forget the insulation between mat and new drywall – it’s essential.
From The SunTouch UnderFloor install manual:
REMEMBER: Proper insulating and sealing of the floor cavity is necessary for the performance of UnderFloor mats.
Drywall ceilings below the mats will require access doors or cover plates if there are joist bay junction boxes. An alternative is to install junction boxes with a cover plate in the space above
upwards.
David Pettigrew says:
[email protected]
Is your product available in Canada
Floor Heat Expert says:
Hi David – apologies for the delay in our response.
Yes, You can find them on http://www.WarmYourFloor.ca
Christy says:
Would this be possible in a condo? I purchased an apartment style condo on the third floor so I have a neighbor living directly under my unit. Would there be a crawl space between floors to install this retro fit?
Floor Heat Expert says:
Hi Christy,
Unfortunately, no, you cannot install Retro-Fit mats between floors.
The mats are made for use in a crawlspace or unfinished basement.
Krystal Moscatello says:
Question: I’m installing a new tile floor over an existing tile floor. Can i install radiant heat in between layer number 1 (existing tile) and layer number 2 (new floor)?
Please advise and thank you!
[email protected] says:
Hi Krystal,
You can install the heating element over an existing floor.
Just want to make sure the floor is as clean as possible and level before installing over it.
Keep in mind you still need mortar if the product requires it.
Please let us know if you need anything else.
Thank you, Krystal!
Eran Nettles Stanley says:
The radiant heat under my bathroom tiles is broken. Would there be any fire or other concerns with installing this product? The tiles are new and I do not want to replace them.Also, would it be ineffective because of insulation installed for the old heater directly on the subfloor?
Michele G says:
I live in northern NJ and I’m researching the different methods for heating the first floor of my home. There is a full basement below, with open joists. There are various water pipes and electrical wires that serpentine throughout the basement ceiling. Would the UnderFloor mats be sufficient to heat the first floor living area, or just the floors?
WarmYourFloor Expert says:
Hi Gail,
The joist bays do need to be open in order to install the mats. And the mats hang down from the ceiling about 2 inches.
The mats can not cross or come in contact with any of the wires or pipes.
You also need to be able to get insulation material into each bays to trap the heat.
So you need enough space to install the mat and insulation materials without obstruction.
Amanda says:
Hi will this heat the room up as well or just the floors? I want to get rid of my radiators but I don’t want to rip my wooden flooring up? I’m looking for a heating system that will heat the house up but can be fitted by going under the floors to install.
Thad Mason says:
I want to use the retrofit version in the crawl space but my floor joists are 24″ on center not 12″ or 16″. What are my options?
Brian Edwardson says:
Can you explain the how to install the insulation?
I’m assuming you’re saying to install insulation just below the heating maps to “trap” the heat against the floor?
Floor Heat Expert says:
Hi Brian – Here’s a link to the install manual – and a direct link to one of the sizes – take a look at the photos, and also there’s a video on that page
UnderFloor Instruction Manual Link
https://kc.warmyourfloor.com/suntouch-underfloor-16-x-4-long-120v-0-4a.html
You can also call us, or reply, and we’re glad to help
And, Yes, install under the mats after placing them in joist bays
Wayne Turi says:
Are there any installers
Floor Heat Expert says:
Hi Wayne, There are many experienced installers for floor heating. More than half of our customers are DIYers, as our products install easily and we have great support documentation, manuals and videos.
Please contact us and we can support you!
866-558-3369
Floor Heat Expert says:
Hello Wayne,
There are many qualified installers of floor heating systems.
The retrofit mats are one of the easiest to install.
In fact, the products are so easy to install, many customers install floor heating as a DIY project. The instructions, videos, and support we offer make floor heating a good project for Do It Yourself installation – for the final step of connection to power, electrical experience is required so ensure you or your installer has those qualifications, or hire a Professional.
Joshua Odom says:
Would this be able to provide adequate heat through the subfloor to the tiling? If so, could it be a hazard to heat through the wood sub flooring? Thanks
[email protected] says:
Hi Joshua,
Yes, the retro-fit mats are designed specifically to heat from the joist bays through the subfloor to the tile.
As long as the joist bays are open and mats are not being installed near wires, pipes or ducts this is safe to use for this application.
Let us know if you have any other questions.
Thank you, Joshua!
Scott Cook says:
Hi Joshua, The retrofit mats that fit in the joist bays are indeed safe – they are designed and safety listed for this very purpose.
While a lower heat output than the mats that sit on top of the subfloor when installing new flooring, they still provide 10 Watts per Sq Foot which translates to approx 34 BTUs/SF/Hour. Remember to insulate under the UnderFloor mats – this is critical to performance. The retro fit mats are a great problem solver and most people are very happy with the results.
Jeanne Lodwick says:
we need a warm floor. do you install? we want to put wood flooring on top.
Jeanne
[email protected] says:
Hi Jeanne,
We do not do installations, just distribution.
These products are not difficult to work with though so any floor contractor and electrician can install this for you.
But keep in mind a nail down hardwood floor would not work with floor heat.
If you’re using an engineered or laminate wood you’re okay.
Rick Berg says:
I am interested in using your product.
I have a small bathroom with ceramic tile. It is about 8 foot by 5 foot.
I have a crawl space. With a dirt floor.
Can you send me information on what I would need?
Scott Cook says:
Hi Rick,
Sounds like your referring to the retrofit mats that install between joist bays, yes?
If so, we need to know the measurements of the bays you have and how many of each size so we can figure out what you’ll need.
You can always send us a quote request with that information using this link here: https://www.warmyourfloor.com/quote-request
Once we have that information from you we can tell you exactly what you’ll need.
Thanks Rick!