Cold Homes & Energy Hub
A home that is cold whatever the heating does, or expensive to run, is almost always losing heat faster than it is made — through the fabric, draughts and cold surfaces, not the boiler.
Book a Diagnostic SurveyComfort and bills are governed by heat loss: the fabric's insulation, the airtightness and the heating efficiency. Measuring where the heat escapes — with thermal imaging and a blower door test — turns a cold, costly home into a targeted, cost-effective fix.
Recommended diagnosis: Heat Loss Investigation
Cold Homes
All 14 guidesWhy is my house always cold?
If your home feels cold however long the heating runs, the problem is rarely the boiler — it is the building losing heat faster than you can replace it. The way to fix that affordably is to measure where the heat is going, not to guess.
Read the guideWhy is one room colder than the others?
A single room that never warms up is rarely random. It almost always has more heat-losing surface, a local defect, or a heating imbalance — and each of those leaves a signature you can measure.
Read the guideWhy are my walls cold?
Cold walls are one of the clearest signs that a home is losing heat through its fabric — and they explain why a room can feel cold even when the air is warm. The cause is usually missing insulation, a thermal bridge, or damp.
Read the guideWhy is my bedroom always cold?
Bedrooms are often the coldest rooms in the house — frequently upstairs, on a corner, heated less, and left to cool overnight. The same conditions that make them cold also cause the morning condensation many people notice on the windows.
Read the guideWhy do I feel cold even when the room is warm?
Feeling cold while the thermostat says the room is warm is one of the clearest signs that comfort depends on more than air temperature. Your body loses heat to cold surfaces by radiation and to moving air by draughts, so cold walls, windows and floors, plus air leakage, can leave you feeling chilly even in warm air. Comfort is set by the surfaces and the airtightness as much as by the heating.
Read the guideWhy is the room above my garage always cold?
A room above a garage is almost always cold for one main reason: its floor sits directly over an unheated, often draughty and uninsulated space, so it loses heat downwards in a way no other room does. The garage is effectively 'outside' thermally — cold, ventilated and sometimes open to the weather — so the floor of the room above behaves like an exposed external surface. Add the extra external walls these rooms usually have, and the cold floor and cold surfaces explain the chill, which is fixable by insulating and sealing.
Read the guideWhy is my kitchen or bathroom so cold?
Kitchens and bathrooms often feel colder than other rooms for a combination of reasons specific to them: they have strong extract ventilation that pulls warm air out and cold air in, lots of cold hard surfaces (tiles, glass, worktops, sanitaryware) that feel chilly and draw heat from you, frequently little or no dedicated heating, and they are often on external corners with extra cold walls. The cold is usually a mix of ventilation, surfaces and heating rather than a single fault, and each part can be addressed.
Read the guideWhy is my hallway and stairs so cold?
Hallways and stairs are commonly the coldest part of a house because they sit at the heart of its air movement: the front door is a major source of draughts and a cold surface, and the stairwell acts as a chimney, with the stack effect drawing cold air in low and warm air up and out through the upper floors. Add the fact that halls usually have little or no heating, and you have a space that is both draughty and under-heated, channelling cold air through the whole home.
Read the guideWhy is my north-facing room always cold?
A north-facing room feels colder because it receives little or no direct sunlight, so it misses the free solar warmth that south- and west-facing rooms enjoy through the day — and it is often the most weather-exposed side of the house too. But while the lack of sun explains why it starts colder and warms up more slowly, a room that is persistently and uncomfortably cold is usually telling you something about its fabric: cold external walls, heat loss through windows, air leakage, or under-heating. The orientation sets the room at a disadvantage, but it is the building's insulation, airtightness and heating that decide whether it is merely cooler or genuinely cold.
Read the guideWhy is my house cold in the morning?
A house that feels cold every morning, even though it was warm the evening before, is losing the night's heat faster than it should. When the heating goes off overnight, a well-insulated, airtight home holds much of its warmth until morning, while a leaky, poorly insulated one sheds it quickly and is chilly by dawn. So a cold morning is less about the heating itself than about how well the building retains heat — its insulation, airtightness and the warmth stored in its fabric. Reaching for a longer heating timer treats the symptom; understanding why the heat disappears overnight points to the fix that makes mornings comfortable and cuts the cost of getting there.
Read the guideWhy is my bungalow so cold?
Bungalows often feel colder and cost more to heat than two-storey homes of similar floor area, and the main reason is their shape: a single-storey home has a large roof and ground floor spread out over its whole footprint, so it loses a disproportionate amount of heat through the top and bottom of the building. Heat is lost in proportion to surface area, and a bungalow has more roof and floor per square metre of living space than a house. Add the typically large area of external wall and the exposure of a low, spread-out building, and the result is a home that sheds heat quickly. The good news is that the same shape means the roof and floor — the biggest losses — are usually very treatable.
Read the guideWhy does my house feel cold and damp?
A home that feels cold and damp at once is suffering from two linked symptoms of one underlying condition: cold surfaces combined with high indoor humidity. Cold, poorly insulated walls and floors both feel chilly and chill the air against them, while too little ventilation lets moisture build up — so the air feels raw and clammy, surfaces stay damp, and warmth never quite arrives. It is not two separate problems but one: a building that loses heat and traps moisture. The remedy is to warm the surfaces, control the humidity and provide ventilation together, rather than chasing the cold and the damp as if they were unrelated.
Read the guideWhy is my living room always cold?
A living room that is always cold usually loses heat faster than its heating can replace it, and the reasons cluster around its construction: living rooms often have a lot of external wall, large windows or patio doors, sometimes a chimney, and may be over an unheated space or on a corner with two cold external walls. Each of these raises the heat loss and lowers the surface temperatures, so the room feels cold even when the radiator is on. Bigger radiators or more heating treat the symptom; the lasting fix is to find which of these losses dominates and address it.
Read the guideWhy is my house colder than my neighbour's?
Two houses that look identical from the street can differ sharply in warmth, because the things that keep a home warm are mostly hidden: insulation that was or wasn't installed, airtightness, the state of windows and draught-proofing, the position in a terrace or block, and how the heating is run. If your home is colder than a neighbour's apparently similar one, the difference lies in one or more of these — and it is measurable. Comparing the two is less useful than measuring your own home to find where it loses the heat the neighbour's keeps.
Read the guideHeat Loss & High Energy Bills
All 12 guidesWhy are my energy bills so high?
If your heating bills feel disproportionate to the comfort you get, the building is almost certainly losing heat faster than it should. The cheapest unit of energy is the one you never have to buy — so the fix starts with measuring where it escapes.
Read the guideWhy won't my house stay warm?
If your home warms up but loses it almost as soon as the heating switches off, the issue is retention — the building cannot hold heat because it is losing it too fast through fabric and air leakage.
Read the guideHow do I find heat loss in my house?
You find heat loss by measuring it, not by guessing. The professional method combines thermal imaging (where heat escapes), a blower door test (how much air leaks and where), and a heat-loss calculation (how much energy is lost) into one diagnostic picture.
Read the guideWhy does my heating need to stay on all the time?
If the only way to stay comfortable is to leave the heating running constantly, the building is losing heat as fast as the system supplies it. That's a fabric-and-airtightness problem, not a reason to accept permanent running costs.
Read the guideWhere does most heat escape from a house?
Heat escapes from a house through every part of its envelope — the walls, roof, windows, doors and floor — and through air leakage, which is often the largest and most overlooked route. The proportions differ from house to house depending on its size, construction and condition, which is exactly why measuring where your home loses heat is far more reliable than assuming, and why it ensures any money is spent on the biggest losses first.
Read the guideIs an EPC enough to plan a retrofit, or do I need a proper survey?
An EPC is a useful headline rating for comparing homes, but it is a standardised estimate based on assumptions, not a measurement of how your specific house behaves. To plan a retrofit that actually works, you need to know your real heat losses, air leakage and moisture risks — which an EPC does not measure. Relying on an EPC alone to choose measures can send money to the wrong place; a proper survey provides the building-specific evidence that good decisions need.
Read the guideDoes insulation really save money?
Insulation does save money — but only when it is put where your home actually loses heat, and in the right order. Heat loss is not spread evenly, so insulating the elements that lose the most (often the roof, then the worst walls and floors) pays back well, while spending on an element that loses little, or insulating without addressing air leakage and thermal bridges, saves far less than expected. The honest answer is that insulation is one of the best investments in a home — provided it is targeted by measurement rather than guesswork.
Read the guideWhat's the most cost-effective way to reduce heat loss?
The most cost-effective way to reduce heat loss is not a single measure but a method: measure where your home actually loses heat, then fix the biggest losses with the lowest cost first, in a sensible sequence. For most homes that usually means cheap, high-impact basics — loft insulation and draught-sealing — before bigger investments like wall or floor insulation and glazing. The key is that the right order depends on your specific home, so a measured assessment is what tells you where to start for the best return.
Read the guideIs it worth getting cavity wall insulation?
Cavity wall insulation can be one of the most cost-effective ways to cut heat loss and bills — but only in a wall that is genuinely suitable, properly assessed and correctly installed. In the right house it works well and pays back quickly; in the wrong one, or done badly, it can bridge the cavity and let damp cross to the inside, causing problems that are expensive to put right. Whether it is worth it for your home therefore depends on the wall construction, the exposure to wind-driven rain, and the condition of the cavity — none of which can be assumed from the fact that you have cavity walls. The sensible step is to establish suitability before installing, not after.
Read the guideShould I get external or internal wall insulation?
For a solid-wall home — one with no cavity to fill — the way to cut the large heat loss through the walls is either external wall insulation (a layer added to the outside) or internal wall insulation (a layer added to the inside), and the two suit different houses. External insulation generally performs better and avoids the moisture risks of internal, but changes the appearance and is more expensive; internal is cheaper and keeps the outside unchanged, but reduces room size and, done without care, can cause condensation within the wall. Choosing well depends on the building, the appearance constraints, the budget and — crucially — getting the moisture detailing right. It is a decision best made on the building physics, not on cost alone.
Read the guideWhy are my energy bills higher than similar homes?
If your energy bills are higher than apparently similar homes, the difference almost always lies in how much heat your home loses and how efficiently it is heated — both largely invisible. Hidden gaps in insulation, more air leakage, a more exposed position, older or poorly controlled heating, and simple differences in how the system is run can each add significantly to a bill while leaving two homes looking identical. The way to explain and close the gap is to measure your own home's heat loss and heating efficiency rather than guess, so the spend that is inflating the bill can be pinned down and reduced.
Read the guideIs it worth insulating my solid walls?
Insulating solid walls is one of the most effective ways to warm a solid-walled home and cut its bills — solid walls lose far more heat than insulated cavity walls — but it is also a major, costly intervention that only pays off when it is done correctly. Whether it is worth it for you depends on how much the walls actually lose relative to the rest of the home, whether internal or external insulation suits the property, and crucially whether the work is detailed to avoid the condensation, damp and thermal-bridging problems that poorly designed solid-wall insulation can cause. The decision should rest on a heat-loss assessment and a moisture-risk appraisal, not on a generic sales pitch.
Read the guideHeating & Warmth
All 15 guidesWhy is my house cold even with the heating on?
When the heating is on but the house still feels cold, it is tempting to blame the boiler. Far more often, the building is losing heat through its fabric — walls, windows, roof and air leakage — as fast as the heating can supply it. The system is working; it is simply pouring warmth into a building that cannot hold it. Understanding that balance is the key to a home that finally feels warm.
Read the guideWhy does my house take so long to heat up?
A home that takes a long time to warm up is fighting two things at once: heat escaping through its fabric and air leakage, and cold surfaces that have to be warmed before the room feels comfortable. The heating is doing work, but much of it is replacing losses or warming up cold mass rather than heating the room. Understanding why warming is slow points straight to how to make it faster.
Read the guideDo I need a bigger boiler or better insulation?
When a home is cold or expensive to heat, the instinct is often to fit a bigger boiler. But a bigger boiler only adds more heat input to a building that may be losing heat too fast — it treats the symptom, not the cause. In most homes, better insulation and airtightness deliver more comfort, lower bills and a smaller heating system. Deciding correctly starts with measuring the heat loss.
Read the guideWhy are some rooms warmer than others?
When some rooms are warm and others stay cold, the heating system and the building are not matched room by room. The cold rooms are usually losing more heat — through exposed walls, more glazing or air leakage — or receiving less, through undersized or poorly balanced radiators. Diagnosing which applies to each cold room is the key to even, comfortable heat throughout the home.
Read the guideWhy are my radiators not getting hot?
Radiators not getting hot has two quite different explanations, and telling them apart matters. The radiator itself may not be heating — trapped air, sludge, poor balancing or weak circulation — which is a heating-system issue a heating engineer resolves. Or the radiators may be working but the room still feels cold, because the home loses heat faster than they can deliver it — which is a fabric problem no amount of radiator work will fix. Knowing which you have decides where the money should go.
Read the guideIs my house ready for a heat pump?
A heat pump can heat almost any home, but it works efficiently and affordably only in one that loses heat slowly and can be warmed with low-temperature water. So the real question is not whether a heat pump will fit, but whether your house is ready to run on the gentle, steady, low flow temperatures heat pumps prefer. That depends on your fabric — insulation and airtightness — and on your radiators and system being sized for low-temperature heat. Getting this right first is what makes a heat pump cheap to run rather than disappointing.
Read the guideHow do thermostatic radiator valves work, and where should I set them?
A thermostatic radiator valve (TRV) controls the temperature of the room, not the heat of the radiator: it senses the air temperature around it and throttles the flow of hot water to the radiator to hold that room at the level you set. The numbers on the dial are not heat settings but target temperatures, so you set each room to the comfort you want — typically a mid setting for living rooms and lower for bedrooms — and the valve does the rest, letting you heat each room only as much as it needs.
Read the guideWhy do I have to turn my heating up so high to feel warm?
If you have to turn the heating right up to feel even reasonably warm, the problem is almost always that your home is losing heat as fast as you can put it in, or that cold surfaces are making you feel cold even when the air is warm — not that the boiler is too weak. Cranking up the thermostat is treating the symptom; the cause is heat loss through poorly insulated fabric, air leakage and cold surfaces. Diagnosing where the heat escapes is what lets you feel warm at a normal, affordable setting.
Read the guideShould I leave my heating on low all day, or only when I need it?
The long-running debate over whether to leave the heating on low all day or only run it when needed has no single answer, because it depends almost entirely on how well your home holds heat. In a poorly insulated home that loses heat fast, heating only when you need it is usually cheaper; in a well-insulated, airtight home that holds warmth, gentle continuous heating can be comfortable and barely more costly. The deeper truth is that the better your fabric, the less the question even matters.
Read the guideDo I need a heat loss survey before getting a heat pump?
Before installing a heat pump, a proper heat loss survey is not an optional extra — it is the step that determines whether the system will work well, run cheaply and keep you warm. A heat pump delivers heat at a lower temperature than a gas boiler and is most efficient when the home loses heat slowly enough to be heated by large, low-temperature emitters. If the heat pump is sized from a rule of thumb or the old boiler's output, rather than from a measured, room-by-room heat loss calculation, it is likely to be wrong-sized, run inefficiently and disappoint. The survey establishes the home's actual heat loss, whether the fabric is ready, and exactly what each room needs — which is what makes a heat pump a success rather than a costly mistake.
Read the guideShould I replace my radiators with bigger ones?
Replacing radiators with bigger ones can be exactly the right move — or money spent on the wrong thing — depending on why the room is cold. A radiator that is genuinely too small for a room's heat loss cannot keep it warm, and a larger one will help; bigger radiators are also essential if you run, or plan to run, your heating at a lower flow temperature, as with a heat pump, because each radiator gives out less heat when the water is cooler. But if the room is cold because it loses heat too fast through poor insulation and draughts, a bigger radiator just burns more fuel to keep up. The right answer comes from knowing the room's heat loss and the flow temperature, not from guessing.
Read the guideWhy is my upstairs too hot and downstairs too cold?
An upstairs that is too warm while the downstairs stays cold is a common pattern, and it usually comes from a combination of three things: warm air naturally rising through the house, a heating system that is not balanced so it over-heats some rooms and under-heats others, and the downstairs losing more heat than the upstairs through its floor, walls and draughts. Heat rises, so without good control the upper floor tends to gather warmth while the ground floor — which sits on the cold ground and often leaks more air — struggles. The good news is that each cause is addressable: balancing the system, reducing downstairs heat loss, and controlling the stack effect all even out the temperatures.
Read the guideWhy is my heat pump not keeping my house warm?
A heat pump that cannot keep a home warm is almost never a faulty heat pump — it is usually a mismatch between the system and the building. Heat pumps deliver heat at a lower flow temperature than a gas boiler, so they rely on the home losing heat slowly, on emitters sized to give out enough heat at that lower temperature, and on a correct heat-loss design behind the installation. When a home is colder than expected after a heat pump goes in, the cause is normally one of three things: the heat loss was higher than the system was sized for, the radiators or underfloor circuits are too small to emit enough heat at low flow temperatures, or the system has been set up or controlled badly. Each is diagnosable, and each points to a different fix.
Read the guideShould I get underfloor heating or radiators?
Whether underfloor heating or radiators is right for your home depends less on preference than on building physics: the heat loss of the rooms, the floor construction, and especially the flow temperature your heat source wants to run at. Underfloor heating spreads heat over a large surface, so it can deliver enough warmth at a low flow temperature — which suits heat pumps and well-insulated homes, and gives gentle, even comfort. Radiators are cheaper and simpler to fit, especially as a retrofit, but need a higher flow temperature unless they are generously sized. The right choice comes from matching the emitter to the heat loss and the heat source, not from assuming one is always better.
Read the guideWhy are my heating bills so high with a heat pump?
A heat pump that produces high bills is usually running inefficiently, and that almost always comes down to one of three things: it is running at too high a flow temperature, it is badly controlled, or the home loses heat faster than it should. A heat pump's efficiency — how much heat it delivers per unit of electricity — depends heavily on running at the lowest flow temperature that still keeps the home warm, on running steadily rather than blasting on and off, and on the building not bleeding heat through poor insulation and air leakage. When bills are high, the heat pump is rarely the fault; the set-up or the fabric is dragging its efficiency down, and both are measurable and fixable.
Read the guideDraughts & Air Leakage
All 11 guidesWhy is my house so draughty?
A draughty house feels cold even when the heating is on, because uncontrolled air is moving through the building, carrying warmth out and pulling cold air in. Draughts are not just an irritation at the doors and windows — they are the visible end of a whole-house air leakage problem, and most of the leakage is in places you cannot feel or see. Understanding how and why air moves through a home is the key to stopping it.
Read the guideWhere do draughts come from in a house?
Most people assume draughts come from the windows and doors, because those are the gaps you can feel. In reality, air leaks through dozens of paths spread across the whole building — many of them hidden at floor level, in the loft, behind units and around every pipe and cable. Knowing where draughts genuinely come from is the difference between sealing the right gaps and chasing the obvious ones.
Read the guideHow do I find and stop draughts?
You can find a few draughts by feeling for cold air, but the leaks that cost you the most are usually the ones you cannot feel. Stopping draughts effectively means locating every significant air leakage path, sealing them in the right order, and keeping the controlled ventilation your home needs. This guide explains how to do that properly, from what you can do yourself to what measurement reveals.
Read the guideShould I seal all the draughts in my house?
It is tempting to seal every draught you can find, but doing so without thinking about ventilation can cause as many problems as it solves. The right goal is not a hermetically sealed house — it is to stop uncontrolled, wasteful leakage while keeping the controlled fresh-air supply a home needs. This guide explains the balance, and how to seal safely.
Read the guideWhy can I feel a draught but can't find it?
A draught you can feel but cannot find is one of the commonest puzzles in an older home, and there are two usual explanations. Either cold air is leaking in somewhere out of sight and tracking across the room to where you feel it — air rarely enters where you sense it — or there is no incoming air at all and you are feeling cold air sliding down off a cold surface, which feels exactly like a draught but is not air leakage. Telling the two apart is the key to fixing it.
Read the guideCan a house be too airtight?
Strictly speaking, a house cannot be too airtight — but it can very easily be under-ventilated, and the two get confused. Airtightness and ventilation are different things: airtightness stops uncontrolled, accidental leakage that wastes heat and causes draughts, while ventilation deliberately supplies fresh air and removes moisture and pollutants. Problems blamed on a home being 'too airtight' — stuffiness, condensation, poor air quality — are really problems of sealing without providing the controlled ventilation that a tight home needs.
Read the guideWhy do I feel a draught from my electrical sockets and switches?
Feeling cold air whisper out of a plug socket or light switch is a clear sign that air is leaking through the wall behind it — usually from a cold, draughty cavity or void that connects to the outside. The socket back-box is open into that space, and the faceplate is not sealed, so whenever there is a pressure difference, air is pushed through the box and into the room. It is a small but telling leak, and it often points to larger leakage paths within the wall.
Read the guideDo trickle vents cause draughts, and should I close them?
Trickle vents — the small adjustable vents in the top of window frames — can feel draughty in cold or windy weather, and it is tempting to close them. But they are providing deliberate background ventilation, and closing them removes the controlled fresh air that keeps the home healthy and dry, often causing condensation and stuffiness. The honest answer is that the slight draught is the price of ventilation, and the better solution is usually to keep them open and address the home's overall airtightness and ventilation properly.
Read the guideHow do I stop draughts around my front door?
Draughts around a front door come from the gaps the door has to leave to open and close — at the bottom threshold, down the sides and top, around the letterbox and keyhole — and sometimes from a more hidden source: air leaking through the gap between the door frame and the surrounding wall. Stopping them well means finding which gaps are actually leaking, because sealing the obvious ones while leaving a leaky frame-to-wall junction, or a poorly fitting threshold, only half-solves the problem. Front doors are also a common point where cold air enters and spills into the hallway, so getting the seal right makes a noticeable difference to comfort. The reliable approach is to locate every leakage path first, then seal each appropriately without stopping the door working.
Read the guideHow do I stop draughts from my floorboards?
Draughts coming up through floorboards are cold air from the ventilated void beneath a suspended timber floor, leaking into the room through the gaps between the boards and around the floor edges. The void is deliberately ventilated by airbricks to keep the timbers dry, so it is cold and breezy, and as warm air rises and escapes higher in the house, cold void air is drawn up through every shrinkage gap. Stopping the draughts means sealing those gaps and the floor perimeter — or insulating and sealing the floor from below — while keeping the airbricks clear so the timbers stay dry.
Read the guideWhy is my house draughty after new windows?
If your home is still draughty after new windows, it is because the windows were only ever part of the air leakage — and often not the biggest part. Draughts come from many paths: gaps around floors and skirtings, the loft hatch, downlighters, service penetrations, chimneys, letterboxes, and crucially the junction where the new windows meet the wall, which is frequently left poorly sealed even when the windows themselves are airtight. Replacing the glazing addresses the glass but not these other leaks, so the house can feel barely less draughty. Finding where the air actually moves — with a blower door test — is what lets the real leaks be sealed.
Read the guideLoft & Roof
All 14 guidesWhy is my loft or roof losing heat?
Because warm air rises, the loft and roof are among the biggest routes for heat to leave a home — and they are also where insulation is most often thin, gapped, compressed or bypassed by air leakage. A loft that feels warm in winter is a loft letting your heat escape. Finding out exactly how and where it is lost is the key to a warmer, cheaper home.
Read the guideWhy is there condensation in my loft?
Condensation in a loft happens when warm, moist air from the house below leaks up into the cold loft space and condenses on the cold roof structure — often made worse by inadequate loft ventilation. Left unchecked it dampens timbers and insulation and can grow mould. The cure is to stop the moist air getting up there and to keep the loft properly ventilated.
Read the guideIs my loft insulation good enough?
Loft insulation can look complete from the hatch and still under-perform badly. Depth is only part of the story: gaps at the joists, compression under boarding, insulation pulled away from the eaves and air leakage through the ceiling all leave it working far below its potential. Judging whether yours is good enough means looking past the surface to coverage, continuity and air-sealing.
Read the guideWhy is my loft room too hot in summer?
Loft and top-floor rooms often overheat in summer because the roof absorbs intense solar heat, thin or gappy insulation lets it through, and the room has little ability to lose that heat or keep it out. Overheating is the summer counterpart of winter heat loss — and the same fabric weaknesses usually cause both. Controlling it is about insulation, shading, ventilation and thermal mass.
Read the guideWhy is my flat roof getting condensation?
Condensation in a flat roof is usually interstitial condensation: warm, moist air from inside the home rises, reaches the cold underside of the roof deck, and condenses there — soaking the insulation and timber from within, often before any sign shows on the ceiling. It is rarely a leak from above; it is moisture from inside meeting a cold surface within the construction. The cure depends on the roof type, but it always comes down to keeping warm moist air away from the cold deck and getting the build-up right.
Read the guideWhy is my loft conversion cold in winter and hot in summer?
A loft conversion that is cold in winter and hot in summer is suffering from the same root cause in both seasons: the roof is the thinnest, most exposed surface in the house, and a room built into it sits right behind that fabric. If the roof slopes, dwarf walls and flat ceiling are not well insulated, airtight and free of thermal bridges, the room loses heat fast in winter and gains it fast in summer — and poor ventilation makes the summer heat worse. The fix is to treat the roof as a high-performance element, not an afterthought.
Read the guideWhy is my loft damp or musty?
A damp, musty loft is usually a condensation and ventilation problem, not a leaking roof: moist air from the house below rises through gaps in the ceiling into the cold loft, condenses on the cold underside of the roof and on the timbers, and — if the loft is poorly ventilated — that moisture lingers, dampening the insulation and timber and producing the characteristic musty smell. The cure is to stop the moist air getting up there and to keep the loft well ventilated, rather than assuming the roof has failed.
Read the guideShould I board my loft for storage, and will it cause problems?
Boarding a loft for storage is fine and worthwhile, but only if it is done correctly — and the common mistake of laying boards straight onto the joists causes real problems. Modern loft insulation is usually deeper than the joists, so boarding directly onto them squashes the insulation, drastically reducing its performance, and can trap moisture and cause condensation. The right way is 'raised boarding', which lifts the boards above full-depth insulation on spacers, giving you storage without sacrificing warmth or risking damp.
Read the guideIs spray foam insulation in my loft a problem?
Spray foam insulation applied to a loft or the underside of a roof can be a problem — and it is increasingly flagged by surveyors and lenders — but whether it is actually causing harm in a particular roof depends on the type of foam, how it was applied, and what it is doing to the roof's ventilation and timbers. The concerns are real: spray foam can trap moisture against the rafters, encourage condensation and rot, hide defects from inspection, and make some lenders unwilling to lend. Equally, not every installation is failing. The sensible approach is not to panic or to rip it out blindly, but to have the roof properly assessed so you know whether it is sound, at risk, or in need of removal.
Read the guideShould I insulate between or above the rafters?
When you are insulating a sloping roof — for a loft conversion or a room-in-roof — the choice between insulating between the rafters, above them, below them, or a combination is not just about cost and headroom; it determines how warm and how condensation-safe the roof will be. Each option has consequences for the depth of insulation you can achieve, the ceiling height you lose, the continuity of the insulation, and crucially how the roof manages moisture. Getting it wrong can leave cold bridges through the rafters or trap moisture against the timber. The right choice depends on the roof construction, the headroom available and the moisture strategy — which is best decided from the building physics, not a single rule.
Read the guideShould I repair or replace my flat roof?
Deciding whether to repair or replace a flat roof is not just about the leak in front of you — it depends on the condition and age of the covering, how the roof is insulated, and whether it is a 'cold deck' or 'warm deck' construction, because those determine both how long a repair will last and whether the roof is at risk of hidden condensation. A patch repair can be sensible for an isolated fault in an otherwise sound roof, but where the covering is near the end of its life, or the build-up is a cold deck prone to condensation and rot, replacement that also corrects the insulation and ventilation is usually the better value. The right call comes from assessing the whole construction, not just the visible defect.
Read the guideShould I get room-in-roof insulation?
Room-in-roof insulation — insulating the sloping ceilings, dwarf walls and flat ceiling of a converted loft or attic room — is usually worth it if the room is cold, hot in summer or expensive to heat, because these rooms have a lot of roof area exposed on all sides and are often poorly insulated. But it only delivers if it is detailed continuously: the insulation must be unbroken across the slopes, the dwarf walls, the little 'eaves' cupboards and the floor of the space behind them, with no gaps where heat can bypass it. Patchy room-in-roof insulation is one of the most common reasons a loft room stays cold despite 'being insulated'.
Read the guideWhy is my loft insulation not working?
If your loft is insulated but the house still loses heat upwards, the insulation is usually being undermined rather than absent — it is gapped, compressed, too thin, or bypassed by air leakage. Loft insulation only works when it is an unbroken, full-depth layer and when air cannot flow around or through it; in practice, missed areas, boards laid straight onto it, gaps around the hatch, downlighters and service penetrations, and air leaking up from the house below all let heat escape. The result is a loft that feels insulated but performs poorly. The fix is to find the weaknesses and restore a continuous, airtight insulated layer.
Read the guideWhy are the ceilings upstairs cold?
A cold upstairs ceiling is a direct sign that heat is escaping through it into the loft or roof above — usually because the loft insulation over that ceiling is missing, thin, gapped or bypassed by air leakage. Because heat rises, the ceilings below a loft are a major route for heat to leave the house, and any weakness in the insulation above shows up as a cold ceiling, sometimes with condensation or a 'ghosting' pattern of marks along the cold joists. The fix lies above the ceiling, in the loft: restoring continuous, full-depth insulation and sealing the air paths so the ceiling stays warm.
Read the guideFloors & Ground Floor
All 7 guidesWhy are my floors cold?
Cold floors are one of the most-felt comfort problems, and they have two clear causes: the ground floor is poorly insulated so heat is conducted away into the cold ground or ventilated void below, and air leaks up through gaps in the floor carrying cold draughts. Because you are in direct contact with the floor, even a slightly cold surface feels uncomfortable — and the fix depends on which mechanism dominates.
Read the guideWhy is my ground floor so draughty?
A draughty ground floor is usually cold air leaking up from the ventilated space beneath a suspended timber floor, through the gaps between floorboards and around the skirtings. The under-floor ventilation is there for a good reason — to keep the timbers dry — but the gaps let that cold air into the room. The fix is to seal the room side without blocking the ventilation the floor structure needs.
Read the guideShould I insulate my floor?
Floor insulation can make a real difference to comfort and heat loss, but whether it is worth it — and how to do it — depends on your floor type, how much it is losing, and the moisture conditions below. Done well it warms cold floors and cuts draughts; done without regard to ventilation and moisture it can cause problems. Deciding sensibly means understanding what your floor is and measuring what it is actually losing.
Read the guideDo I have damp under my floorboards?
Damp under the floorboards of a suspended timber floor usually shows up as a musty smell, cold or damp-feeling floors, or — in worse cases — soft, decaying timber. It is generally caused by poor under-floor ventilation, ground moisture in the void, or blocked air bricks, and left unchecked it can rot the floor structure. Confirming whether you have it, and why, is the first step to protecting the floor.
Read the guideShould I insulate my concrete or solid floor?
A solid concrete ground floor can lose a meaningful amount of heat and feel cold underfoot, so insulating it is often worthwhile — but unlike a suspended timber floor, which can usually be insulated from below, a solid floor has to be insulated from above (raising the floor level) or as part of a larger dig-out, which makes the decision more involved. Whether it is worth it depends on how much heat the floor actually loses, the practicalities of raising the floor against doors, stairs and ceiling heights, and whether you are already planning works that make it easy. The right answer comes from weighing the heat loss against the disruption — ideally informed by a measurement of where the home loses heat.
Read the guideWhy is there a cold draught coming from under my skirting?
A cold draught at the bottom of the wall, where the skirting meets the floor, almost always means cold air from the void beneath a suspended ground floor is leaking up into the room through the gap there. Suspended timber floors are deliberately ventilated underneath by airbricks to keep the timbers dry, so the void is cold and breezy; where the floorboards meet the wall, and the skirting doesn't seal the junction, that cold air is drawn into the room — especially as warm air rises and escapes higher up, pulling replacement air in low down. It is a classic, very fixable air-leakage path.
Read the guideShould I insulate a suspended timber floor?
Insulating a suspended timber ground floor is usually well worth it if the floor is cold and draughty, because these floors sit over a cold, ventilated void and lose a lot of heat both by conduction and by air leaking up through the boards. Done properly — insulation supported between the joists with the air leakage sealed, while the void's airbricks are kept clear — it warms the floor, stops the ankle-level draughts and cuts heat loss noticeably. The key is to combine insulation with airtightness and to preserve the under-floor ventilation that keeps the timbers dry, so the floor is warm without putting the structure at risk of rot.
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