Underfloor Heating for New Builds vs. Renovations: What Trade Installers Need to Know

When it comes to underfloor heating, one size definitely doesn’t fit all. Especially when you’re comparing new builds to renovations. If you’re a trade installer, project manager, or specifier, understanding the different approaches, system options, and compliance requirements is not just helpful. It’s essential. Get it right, and you can streamline projects, avoid expensive mistakes, and deliver comfort that really lasts.

I’ve been on both sides of the spectrum more times than I can count. One week it’s a pristine new build where everything is laid out like a blank blueprint just waiting to be brought to life. The next, I’m crawling under the suspended floor of a 1930s semi wondering how the heck we’re going to integrate pipework without butchering the original structure.

Each scenario has its quirks. Let’s dig into what makes them tick.

The Installation Game: New Builds vs Renovations

New builds give you freedom. Renovations need finesse.

In new builds, you’re often working with fresh concrete screeds, predictable levels, and open schedules. You’ve got the luxury of planning the UFH system as part of the overall design. That means wet systems. Hydronic underfloor heating. Are almost always preferred. Why? Because you can embed piping right into the screed, ensuring excellent thermal mass and energy efficiency down the line.

With renovations, it’s a different ballgame entirely. You’ve got existing subfloors, restricted build-up heights, and clients who may not want total upheaval. Dry systems or low-profile retrofit panels start to look mighty appealing here. These don’t require the thickness of screeded systems and can often be laid on top of existing structures with minimal height increase.

“The trick with renovations is knowing what you’re dealing with before you even quote. Is the subfloor timber, concrete, or a patchwork of both? What’s the ceiling height left to play with? Get these wrong, and you’re in for a world of callbacks.”

Choosing the Right System for the Right Situation

So, what systems make the most sense?

New Build Favourites

• Screeded wet systems: Ideal for concrete or hybrid slabs. Systems like those from ThermRite really shine here. Excellent heat retention and complete integration with heat pumps. Best bang for your eco-buck.
• Pre-insulated systems: Some projects use EPS insulation boards like ThermRite PRO Overlay Panels with integrated channels for pipework. These can speed up installs in volume housing builds.

Renovation-Friendly Options

• Low-profile overlay boards offer great versatility for timber floors and mixed substrates.
• Electric UFH systems: More common in single-room renovations. Easy install, but usually higher running costs.

Whatever your poison, match the system to the client’s expectations, property type, and the realities of the existing build. Push a screeded system into a Victorian terrace without checking joist depths properly, and you could be explaining cracks and delays to a very unhappy homeowner.

Project Planning: Time, Trades & Trouble

Underfloor heating isn’t installed in a vacuum. And timing it right can make or break a schedule.

In new builds, you’re often coordinating with first-fix plumbing and concrete pouring schedules. If you’re not on-site the morning of the screed, miss one check, and the slab gets poured over incorrectly buried pipes, you’re in deep water.

Renovations need more reconnaissance. Floor removal, condition checks, screed tests (if any), substrate levelling. It all adds up. Mistakes here don’t just delay installs. They can delay the entire project. Communicate early with other trades. Sparkies, chippies, plasterers. And make sure everyone agrees on sequencing.

From experience, your best bet is always to walk the site before materials arrive. Take measurements, photos, and lots of notes. Projects can pivot fast. Be the one who saw it coming.

Compliance, 2025 Style: What the New Regs Demand

As of April 2025, the UK has tightened the screws on building regulations in a big way. The Future Homes Standard isn’t just around the corner. It’s on-site.

That means:
– All-new dwellings must meet improved U-values and be heat pump ready
– Advanced controls are mandatory, including room-by-room programmability
– Maximum flow temperatures have dropped, so underfloor systems need to work efficiently at 35°C to 45°C. That makes UFH an ideal match.

For existing homes, things are a little more flexible. But if renovations trigger ‘material alteration’ status. Like changing a floor structure or installing a new heat source. Expect to demonstrate compliance. Always coordinate with the project’s energy assessor or SAP consultant.

Verified guidance can be found directly from the UK government’s Building Regulations portal (gov.uk), and installers should refer to the latest guidance for Part L and Part F changes updated May 2025.

Drawing on Experience: Suppliers You Can Trust

When choosing a supplier, prioritise one with:
– Strong trade support, technical drawings, and install guides
– Stock availability and regional warehousing
– Site support for complex projects
– Verified compatibility with heat pumps and modern boilers

If you’re running a business, partner with a supplier who doesn’t just sell kits. But supports you through aftercare, training, and compliance queries. We’ve been working with one regional wholesaler for over a decade. And when a slab pour nearly covered our manifolds on a Friday evening, they literally sent someone out with extra risers on a Saturday. That kind of loyalty? You don’t forget it.

The Takeaway

Whether you’re walking into a bare concrete shell or tiptoeing around antique floorboards, underfloor heating demands a tailored approach. New builds give you the full canvas. Renos are like working around the existing brushstrokes. But both can deliver incredible comfort and efficiency when done right.

Know your timelines. Know your systems. Stay ahead of the regs. And never underestimate the power of a good supplier.

Looking to level up your next UFH install? Get in touch with a trusted supplier who understands your projects and can walk with you every step of the way. From quote to commissioning. Don’t settle for “off-the-shelf” when you could have expert-backed, build-specific solutions.

Frequently Asked Questions

What’s the best underfloor heating system for a renovation project?

Low-profile, dry systems are usually the go-to for renovations. They work well with existing subfloors and keep height build-up minimal. Brands like ThermRite offer great options, especially for timber floors. Electric systems can also be a good fit for small-area upgrades like bathrooms.

Can you install wet underfloor heating in an older property?

Yes, but it depends on the floor construction and available build-up height. Wet systems can be used in older homes if you’re digging up floors or replacing screeds, but otherwise, you’ll likely need a retrofit-friendly alternative. Always inspect floor joists, insulation levels, and existing floor heights before recommending a system.

Are all underfloor heating systems compatible with heat pumps?

Most modern hydronic underfloor systems are heat pump-friendly, especially those designed to run at lower flow temperatures. You’ll want to select a system that works efficiently at around 35-45°C. Always confirm with the UFH manufacturer and the MCS-certified heat pump installer to avoid mismatches.