Is insulating pipework a good idea or not? Here we explain the science and common scenarios to consider.
Do you have a modern condensing boiler or heat pump?
If so, you may be wondering whether or not to have your indoor heating pipework insulated.
In this guide, we’ll answer this very question and explore what it means to insulate pipework.
We’ll also explore a range of additional frequently asked questions related to the topic.
Let’s dive in!
Should You Insulate Pipework in Your Home?
The Thermal Envelope
First and foremost, it’s important to define the concept of a thermal envelope in explaining whether or not insulating certain heating pipework would be beneficial or not.
The thermal envelope refers to any part of the property with primary insulation.
However, this is not the same as the boundary between the interior and exterior of a household.
What’s more, the thermal envelope may not cover all pipework inside the property since it's entirely possible for pipework to exist inside a household and not be insulated.
Ideally, a thermal envelope should act as a way of keeping heat within your property.
Pros and Cons of Leaving Pipework Uninsulated
Whether or not you should insulate your heating pipes really depends on where they are and how your home is set up.
If your pipework sits inside your home’s thermal envelope (the parts of your home that are already heated), adding insulation might not save you much energy at all.
Let’s take a closer look at why - and when it still makes sense.
Why You Might Not Need to Insulate Internal Pipework
When heating pipes run through rooms that you already want to keep warm, any heat “lost” from the pipes isn’t really lost - it’s just warming the space around them.
In that case, the pipework acts like a mini radiator network.
So insulating it could actually reduce how much gentle background heat you get for free.
There are a few other reasons you might skip insulation too:
Cost and effort – insulating buried or hidden pipes can be fiddly and time-consuming.
Limited benefit – inside the heated parts of your home, insulation often makes little measurable difference.
Sustainability – insulation materials themselves have a carbon footprint, so installing them where they’re not needed isn’t exactly eco-friendly.
The Upside of Leaving Pipes Bare
Uninsulated pipes can do more good than harm in the right places.
They can:
Top up room warmth naturally without running the boiler harder.
Increase the system’s surface area, spreading heat more evenly.
Allow you to lower your flow temperature, helping condensing boilers or heat pumps run more efficiently.
In simple terms, if that heat stays within your home, it’s not wasted - it’s just being delivered differently.
Think of it like your home being a closed oven: heat escapes the pipework, but it’s trapped inside the “oven” of your house rather than drifting outside.
The Flip Side: When Uninsulated Pipes Waste Energy
Of course, it’s not all upside.
If pipework runs through unheated areas - like lofts, garages, or underfloor voids - any heat escaping there really is lost.
That’s where pipe insulation earns its keep.
You might also lose some efficiency where pipes are close to external walls or poorly insulated floors.
In those cases, insulating them will prevent unwanted heat loss and reduce strain on your boiler or heat pump.
If leaving pipes bare lets you lower your flow temperature without losing comfort, that may offset any small inefficiencies.
If not, insulation will usually win out.
A Quick Note on Heat Zoning
It’s worth mentioning that zonal heating can have similar drawbacks.
Turning radiators off in certain rooms can make the ones left on work harder and hotter, sometimes cancelling out the savings you hoped to make - especially on cold days.
Should You Insulate the Internal Heating Pipework?
In most homes, insulating internal heating pipes won’t make a huge difference — and in some cases, it can even make your system less efficient.
If your pipework runs through rooms that you already want to heat, leaving it bare can help spread warmth naturally while avoiding the extra cost, time, and materials involved in insulating it.
So on the surface, the case for not insulating looks pretty strong.
That said, there are still situations where insulation makes sense - and professional guidance is always worth seeking.
When Insulating Pipework Might Be the Better Option
According to CIBSE (the Chartered Institution of Building Services Engineers), heating pipework should generally be insulated unless leaving it exposed helps a space meet its normal heating demand.
In simple terms:
If uninsulated pipes help keep a room comfortably warm, leave them bare.
If they’re causing unwanted heat or inefficiency, insulate them.
Here are a few examples where insulation is the smarter move:
1. To Avoid Overheating Certain Areas
If you’ve got uninsulated pipes running under a well-insulated hallway, you might find that area becomes too warm, even when the rest of the house feels fine.
Insulating those pipes helps control room temperatures and keeps things comfortable - particularly in homes with zoned heating systems.
Overheating is a bigger concern in commercial buildings that rely on zonal control, but it can still crop up in domestic setups.
2. To Keep Heat Out of Cool Zones
If you’ve set up zonal heating, you’ll want to insulate pipes in zones designed to stay cooler - like spare rooms or unused spaces.
Otherwise, any exposed pipework could undo your zoning efforts by warming areas you’re intentionally keeping cool.
3. To Reduce Noise
Insulating pipework can also dampen noise.
If you’re hearing the pinging, ticking, or rushing sound of water through pipes, adding insulation can help make your system quieter and less distracting.
Other Things to Keep in Mind
When fitting a new heating system (for example, a heat pump), it’s best to speak with your installer early about how the pipework will be treated.
Some systems require insulation for efficiency or safety, and not all installers will leave this up to customer preference.
Your decision will also depend on:
The type and layout of your property
Whether you use zonal heating
Your installer’s recommendations and warranty terms
The Bottom Line
For most modern homes - especially new builds - insulating every inch of internal pipework isn’t always necessary or even beneficial.
It often happens more out of habit than performance need.
Still, there’s no one-size-fits-all answer. In homes where overheating, noise, or zoning conflicts are an issue, pipe insulation can make a noticeable difference.
If you’re unsure, talk to your installer or heating engineer for tailored advice.
For a deeper look at how insulation affects overall performance, check out our full guide on how to calculate heat loss in a property.
