Underfloor Heating Paperwork: Layout Plans and Records to Keep

Installing underfloor heating (UFH)—whether a wet hydronic system or electric heating matting—is one of the most popular modern home improvements. However, because the entire distribution network is buried beneath screed, timber subfloors, or tiles, it is completely invisible once finished. When something stops heating evenly, or when a future renovation requires drilling into the floor, having comprehensive installation records becomes essential.

Far too many homeowners are left with just a wall thermostat and no technical documentation. Keeping a complete record of your underfloor heating installation protects your investment, simplifies maintenance, and prevents costly mistakes during future flooring or building work.

As-built layout drawings and manifold schedules

Before pipework or heating cables are covered, your installer should produce or finalize an as-built layout plan. Unlike initial design estimates, an as-built drawing reflects where the pipes and loops were actually laid across each room.

• Zone and loop layouts: Detailed diagrams showing the exact route, spacing, and perimeter margins of each pipe loop across the floor.
• Manifold connection charts: A clear schedule identifying which manifold port and actuator controls each specific room or heating zone.
• Floor sensor locations: Accurate markings showing where subfloor temperature probes are embedded within the screed or floor structure.
• Unheated margins and exclusions: Notes on where pipes were intentionally omitted, such as beneath fitted kitchen islands, heavy cabinetry, or bathroom sanitaryware.

Pressure testing logs and screed commissioning records

Hydronic underfloor heating systems must undergo hydraulic pressure testing before, during, and immediately after the screeding process. This confirms that pipes have not been kinked, punctured, or improperly joined prior to being permanently encased in concrete or liquid screed.

You should request and retain the signed pressure test log from your heating engineer, confirming the test pressure (typically several bar above normal operating pressure) and the hold duration. Alongside this, keep the thermal commissioning log. Liquid and sand-cement screeds require a specific chemical curing period followed by a controlled heating ramp-up—raising water temperatures gradually over days or weeks—to prevent thermal shock and floor cracking. Retaining the commissioning schedule demonstrates that the floor was brought up to temperature correctly in accordance with manufacturer guidelines.

Electrical certificates and control schematics

Underfloor heating systems rely on an interconnected set of controls, including motorised actuators, wiring centres, circulating pumps, and programmable thermostats. If a new electrical circuit or fused spur was added to power the manifold or electric mats, the installation falls under Part P of the Building Regulations in England and Wales. You should receive a Minor Electrical Installation Works Certificate or an Electrical Installation Certificate from a registered electrician.

In addition to compliance certificates, keep user manuals and wiring schematics for the wiring centre and programmable thermostats. If a heating engineer or electrician attends in the future to replace a failed actuator or upgrade a thermostat, having the exact wiring diagram saves significant diagnostic time.

Photographs and long-term record keeping

High-resolution photographs taken immediately before the screed is poured or the subfloor is laid are invaluable. Photograph each room systematically, using fixed reference points such as doorways or external walls, and include a tape measure in the frame to record pipe spacing and distances from walls. Capturing the manifold while it is clearly labelled provides an additional layer of clarity.

Storing these drawings, pressure logs, photos, and trade certificates in a single digital property logbook, such as Project Passport, ensures that critical technical details remain accessible for the lifespan of the property. When it is time to service the system, change a floor covering, or sell your home, having an organized record removes guesswork and demonstrates diligent property care.