New Build Heating Problems: What to Check If Your Home Is Not Warming Properly

Moving into a new build should not mean accepting rooms that will not warm up, radiators that stay cold or heating controls nobody has explained. Some early problems are caused by unfamiliar settings or commissioning adjustments, while others need the developer or installer to investigate.

The useful first step is to identify the symptom without dismantling equipment or attempting repairs you are not qualified to carry out. A clear record of what is happening, where it happens and when it started can make the developer's after-sales team much more effective.

Heating is already one of the areas that can appear in a broader snagging inspection. If you are checking the whole property, start with our guide to the most common new build snags or see what a professional snagging survey checks.

Are heating problems normal in a new build?

A new heating system can take time to understand, particularly where the property uses multiple zones, smart controls, underfloor heating or a heat pump. That does not mean persistent poor heating should be dismissed as normal.

The distinction is between a system behaving as designed but being set up incorrectly for your routine, and a system that cannot deliver the expected heating because something is faulty, unbalanced, incorrectly commissioned or unfinished.

If you cannot reach a reasonable indoor temperature, one or more areas consistently fail to heat, controls do not respond, error codes appear or the system repeatedly loses pressure, record the problem and report it rather than repeatedly resetting or altering technical settings.

Start with the heating controls

Modern heating systems can have several layers of control: a programmer or schedule, a room thermostat, thermostatic radiator valves, separate zones, hot-water settings and sometimes an app. Energy Saving Trust guidance recommends using the manufacturer's instructions for the specific controls installed in your home.

For many boiler-based systems, common controls include a programmer, room thermostat and thermostatic radiator valves. Energy Saving Trust says a typical comfortable room-thermostat range for many people is around 18C to 21C, although individual needs vary.

• Check that the heating is actually scheduled to be on at the time you are testing it.

• Check the target temperature on the room thermostat.

• Make sure thermostatic radiator valves are not all set low or closed.

• If the home has zones, check each zone rather than assuming one thermostat controls the whole property.

• Look for obvious warning lights or error messages and record them exactly.

• Use the manufacturer manual for user-level controls rather than guessing at installer settings.

What if the radiators are not getting hot?

The pattern matters. If every radiator is cold, the issue may be different from one radiator staying cold while the rest of the home heats normally. If only one room is affected, note whether the radiator is completely cold, partly warm or simply not strong enough to heat the space.

Do not remove covers, open a boiler or interfere with gas, electrical or pressurised components. Safe user checks are limited to the controls and actions the manufacturer documentation specifically allows. If the system requires technical work, report it to the developer or use an appropriately qualified engineer.

Why is one room in my new build much colder than the others?

A single cold room can point to several possibilities: a control or valve setting, a radiator or underfloor-heating zone not operating correctly, an issue with system balancing, or a problem unrelated to the heating appliance itself such as a draught, insulation gap or poorly sealing window or door.

Compare rooms under similar conditions. Record the thermostat setting, outside conditions if useful, which doors are open or closed and the temperature achieved after the system has been running for a reasonable period. This gives the after-sales team something more specific than 'the bedroom feels cold'.

What about underfloor heating in a new build?

Underfloor heating can behave differently from radiators. It may warm the room more gradually and can be divided into separate thermostat-controlled zones. If your property has underfloor heating, ask the developer for the operating instructions and the commissioning or handover information available for the system.

If one zone never warms, the thermostat is unresponsive or the floor remains cold despite the system calling for heat, log the affected room and the control behaviour. Avoid changing installer menus or manifold settings unless the manufacturer documentation says they are intended for normal user adjustment.

What if your new build has a heat pump?

A heat-pump system can feel different from a traditional boiler because it may be designed to run for longer at lower flow temperatures. Turning the thermostat dramatically higher does not necessarily make the home heat faster.

That makes the handover explanation particularly important. Ask what normal operation should look like for your exact system, which settings are intended for daily use and what signs indicate a fault. If the home is not achieving the expected temperature, report the performance rather than trying to force the system through unfamiliar technical settings.

Check whether hot water and heating fail together

When reporting a problem, tell the developer whether you have lost space heating, hot water or both. That simple detail can help the installer narrow down the issue.

• No heating and no hot water.

• Hot water works but radiators or underfloor heating do not.

• Heating works in one zone but not another.

• System works intermittently or only after a reset.

• Heating runs but rooms remain much colder than expected.

• Controls show an error or lose connection repeatedly.

Could the problem actually be ventilation or condensation?

A home that feels cold or damp can lead buyers to focus on the heating even when ventilation and moisture are part of the problem. New homes contain construction moisture and need appropriate ventilation while they dry.

Do not block trickle vents, extract ventilation or other designed ventilation simply to make the property feel warmer. Persistent condensation, mould or unusually high moisture deserves its own investigation. Read our guide to new build condensation and mould for the checks to make.

Should the developer have explained the heating system?

Buyers should receive enough handover information to operate the home safely. The New Homes Quality Code includes requirements around information and the completion process for homes sold by registered developers, and current buyer protections include a structured after-sales process.

If your home is covered by the Code and the controls were not properly demonstrated, ask the developer for a clear explanation and the relevant manuals. For homes reserved from registered developers from 2 March 2026, the current Version 2 of the Code applies.

How to report a new build heating defect

Use the developer's formal after-sales channel rather than relying only on a conversation with someone on site. Written reporting creates a record and makes it easier to show whether the issue is recurring.

• Describe the exact symptom and the rooms affected.

• Record when you first noticed it and whether it is continuous or intermittent.

• Include photos of control screens or error messages where useful.

• State the thermostat setting and whether other zones, radiators or hot water are working.

• Ask for a reference number and the next action or appointment date.

• Keep a log of visits, temporary fixes and whether the fault returns.

The New Homes Quality Board says developers covered by its Code should provide an after-sales process for two years following completion and should aim to resolve snags or defects within 30 calendar days, with the Code allowing for situations where a significant reason causes delay. Your exact rights depend on the developer, applicable Code, warranty and contract.

When is a heating problem more urgent?

Treat safety issues differently from an ordinary snag. If you smell gas, suspect carbon monoxide, see signs of electrical danger, have uncontrolled water leakage or believe equipment is unsafe, stop treating the issue as routine troubleshooting and use the appropriate emergency or qualified professional service for your area.

Do not open sealed heating appliances or attempt gas, electrical or pressurised-system repairs yourself. For a simple lack-of-heat complaint without an immediate safety risk, the developer's emergency or after-sales contact should tell you how they classify the issue.

Could a snagging survey help?

A snagging inspection can be useful when the heating problem sits alongside other concerns about the home's finish or systems. The scope varies by inspector, so confirm what functional heating checks are included before booking.

Use our snagging company directory to research providers and read is a snagging survey worth it? for the wider pros and limitations.

New build heating problem checklist

• Read the user instructions for the exact thermostat and heating system.

• Check schedules, target temperatures, radiator valves and zones.

• Record which rooms heat normally and which do not.

• Note whether hot water is also affected.

• Photograph error messages and control settings where useful.

• Do not alter installer-only settings or open appliances.

• Report persistent issues through the developer's written after-sales process.

• Keep a timeline of appointments and repeat faults.

• Escalate genuine safety concerns through the appropriate emergency route.

• Consider an independent snagging inspection if the heating issue is part of a wider pattern of defects.

The bottom line

A new build heating problem should not be ignored just because the system is unfamiliar or the home is newly completed. Start with safe user-level checks, learn how the installed controls are supposed to work and gather clear evidence of the problem.

If the home still will not heat properly, report it promptly and keep the issue documented. Then use the wider snagging and build-quality guides, new build warranty guide and developer profiles to understand the next steps and after-sales context.