Retrofit Underfloor Heating | Nu-Heat LoPro® Systems UK
Retrofit Underfloor Heating Without Ripping Up Floors
How Sable Uses Nu-Heat LoPro® in Real Renovations
How Nu-Heat’s low-profile systems allow Sable to add warm floors, better comfort and cleaner interiors to existing homes — without the disruption most people fear.
“I’d love underfloor heating… but I can’t face the disruption”
This is one of the most common things Sable hears on renovation projects.
Homeowners love the idea of warm floors, clean walls and modern comfort — but they picture weeks of dust, broken concrete, raised floor levels and spiralling costs.
The belief is simple and understandable:
“I’d love underfloor heating, but I’m not ripping up perfectly good floors to get it.”
The reality is that this used to be true.
It isn’t anymore.
Nu-Heat has developed retrofit underfloor heating systems specifically so you don’t have to excavate your home to enjoy modern comfort — and Sable Projects uses those systems to turn “too disruptive” ideas into smart, realistic upgrades.
The reality of renovation projects
Retrofit work comes with real constraints. Anyone who works on refurbishments knows that no two properties are the same.
Older homes often involve:
Mixed floor constructions (solid slabs, timber joists, suspended floors)
Variable insulation and glazing performance
Existing floors clients want to keep intact
The concerns are always practical:
How much height can we afford to lose?
Will this create unnecessary mess?
Will the system actually perform, or are we guessing?
There’s a simple principle here:
If you’re already investing heavily in a renovation, you shouldn’t have to wreck your home just to enjoy modern comfort.
Nu-Heat’s retrofit answer: LoPro® and overlay systems
Nu-Heat has designed underfloor heating systems specifically for retrofit and renovation scenarios — not adapted new-build solutions.
The most commonly used option is the LoPro® low-profile overlay range, designed to sit on top of existing floors.
Key advantages:
Installed over existing solid or timber floors
No need to dig up the structure
Build-ups as low as 15 mm in many cases
Tiles, laminate and other finishes can be laid directly over the system (subject to substrate condition)
Where floors are already being opened up, Nu-Heat also offers:
Between-joist systems
Integrated solutions with minimal or zero additional height build-up
This gives Sable flexibility — not a one-size-fits-all answer.
How Sable decides what’s possible — and what’s sensible
Retrofit underfloor heating isn’t a box you drop into a house. Sable approaches it as a design problem first.
Every project starts by assessing:
Floor structure (solid slab vs joists)
Existing and proposed insulation levels
How much floor height can realistically be added at doors, stairs and thresholds
Using Nu-Heat’s design tools — including the UFH Selector Tool — Sable narrows the options to what actually works:
LoPro® overlay systems over sound existing floors
Between-joist or integrated systems where floors are already being reworked
Hybrid solutions, where UFH is used in primary living spaces and radiators remain elsewhere
Crucially, every option is backed by room-by-room heat loss calculations and bespoke system design, so performance is engineered in — not assumed.
Retrofit comfort doesn’t mean compromise
A common concern is that retrofit systems are “second best” compared to new-build underfloor heating. Nu-Heat is very clear on this point: that’s only true if the system is poorly designed.
When heat losses, insulation and glazing are properly accounted for, a retrofit underfloor heating system can fully meet the heating demand of a renovated home.
There are also differences that many renovators actually prefer:
Overlay systems heat up and cool down faster, behaving more like radiator systems
Screed-based systems (used in extensions or major refurbishments) warm more slowly but deliver very stable, even heat
Sable ensures controls are matched to the system type:
Screed UFH often runs with setback temperatures, acting as a thermal store
Overlay UFH is typically schedule-driven, similar to radiators
The result is comfort that feels natural for the way the home is actually used.
What retrofit installation really looks like on site
Disruption is often the biggest fear — so it’s worth being specific.
A typical Sable retrofit workflow looks like this:
1. Survey and design
Sable and Nu-Heat confirm the right system type, complete heat loss calculations and produce a tailored design.
2. Preparation
Existing floors are checked for level and soundness. Any insulation upgrades are identified early, not discovered mid-install.
3. Overlay installation
Nu-Heat LoPro® boards (or the chosen system) are laid over the existing floor. Pipework and manifolds are installed exactly as designed.
4. Floor finishes and commissioning
Final floor finishes are installed.
Sable pressure-tests, commissions and sets controls so the system performs correctly from day one.
In many cases:
Concrete slabs remain untouched
Timber floors are handled from above or between joists
Structural disruption is far less than people expect
Two real-world scenarios Sable works with all the time
Scenario 1: Cosmetic renovation, minimal disruption
A client is updating kitchens, finishes and décor but wants warm floors downstairs.
Sable installs a Nu-Heat LoPro® overlay system over sound existing floors, finished with tiles in circulation spaces and engineered timber in living areas.
Outcome:
Minimal structural work
No radiators in key rooms
Even comfort and reliable performance backed by proper design
Scenario 2: Major renovation with structural changes
A large refurbishment involving knock-throughs, an extension and insulation upgrades.
Sable uses screed UFH in the extension and integrated or joist-based systems in reworked areas — all designed by Nu-Heat as one coherent system.
Outcome:
Consistent comfort across the whole ground floor
Efficient low-temperature operation
Ideal integration with a heat pump or modern boiler
Different projects. Same result: comfort, efficiency and design freedom without unnecessary disruption.
Why supplier choice matters more in retrofit projects
Nu-Heat is clear on this: renovation projects place greater demands on design accuracy because existing insulation, glazing and structure must be carefully considered.
A good supplier should:
Guide system selection, not just sell components
Provide room-by-room heat loss calculations
Offer long-term technical support
Nu-Heat does all of this.
Sable adds:
On-the-ground experience in complex refurbishments
Clear communication with homeowners and design teams
Installation that follows Nu-Heat’s designs and manuals precisely, protecting performance and warranties
That combination is what turns retrofit UFH from a risk into a smart upgrade.
Let’s see what’s possible in your home
If you’re renovating and considering underfloor heating, the smartest first step is to understand what’s actually possible — and what’s worth doing.
👉 Book a Nu-Heat retrofit underfloor heating assessment with Sable Projects
You’ll get:
A review of floor construction and insulation
Honest guidance on where overlay UFH makes sense — and where it doesn’t
Clear expectations on cost, disruption and performance
If you’re not ready to talk yet, start with insight instead.
Take time to explore Nu-Heat’s retrofit underfloor heating resources and review how Sable approaches renovation projects. That way, when you do start the conversation, you’re asking the right questions and making decisions with confidence..
You don’t need to tear your home apart to enjoy warm floors.
With the right system and the right installer, retrofit underfloor heating can be one of the most rewarding upgrades you make.
Internal – Sable Projects
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