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Insulation and acoustics knowledge
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Reduce heatRoof, ceiling, wallsBlock noiseNoise from next doorReduce echoMeeting rooms, hallsStop condensationAC and chilled-water pipesAir-conditioningDucts, wraps, linersPipe insulationType, bore, installationFire protectionDatasheet terms, tested systemsHigh temperatureSteam lines, furnaces, boilersChoose a materialGlass wool, stone wool, rubber, PEUnderstand the specsλ, R, U, NRC, STC
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- Getting startedWhere to start when choosing insulation
- Getting startedQuestions to ask before buying insulation
- Sound and acousticsSound insulation vs sound absorption
- Thermal insulationHow heat gets into a building
- Pipe insulationWhy AC and chilled-water pipes drip
- ComparisonsStone wool vs glass wool — what is the difference?
Knowledge by topic
Getting started 3 articles
Thermal insulation 9 articles
- How to choose roof insulationChoose by where it goes, λ and thickness
- How heat gets into a buildingConduction, convection, radiation — and the paths through roof, walls, windows and leaks
- Choosing insulation for a metal-sheet roofCheck the roof first: rolls for single skin, slabs for double skin, then compare R at real thickness.
- How insulation saves air-conditioning energyInsulation cuts roof heat so the air-conditioner works less; there is no fixed %, it depends on the roof's share and use.
- Water dripping under a metal roof with no rainThe steel is colder than the air's dew point: fix with insulation, continuous vapour control and ventilation.
- Fixing a hot west-facing wallShade outside first, then add an inner lining with an air gap, insulation and a reflective layer.
- How to choose insulation thicknessThicker means higher R, but each step saves less — no single thickness fits every job
- How reflective foil (radiant barrier) worksCuts radiant heat, needs an air space, loses effect with dust, complements insulation
- How to insulate a ceiling properlyFull coverage, no gaps, keep clear of hot lights, check ceiling load, work safely
Sound and acoustics 20 articles
- Sound insulation vs sound absorptionWhy panels on the wall do not stop noise from next door
- Do absorption panels stop noise leaving a room?Absorption panels cut echo inside a room but block little sound; blocking needs the whole wall system and sealed leaks.
- Why cavity insulation improves sound insulationCavity insulation absorbs sound bouncing inside a double-leaf wall and works fully only in a correctly built wall system.
- Echoey meeting room: ceiling or walls?Start with the ceiling, add the rear wall when needed; calculate the amount from room size and target RT, then measure.
- Reverberation and reverberation time (RT)RT is the time for sound to drop 60 dB after the source stops; it depends on room volume and absorption.
- Soundproofing a music room, drum room or home theatreTwo jobs: keep sound in and make the room sound good, with doors, floors and air-con planned from the start.
- Improving a party wall to hear less from next doorAdd a decoupled lining with full-cavity insulation, two board layers and airtight sealing, and check flanking
- Loud, echoey restaurants and cafésHard surfaces and raised voices make a venue loud; add absorption at the ceiling and upper walls — it won't block sound.
- Sound-absorbing ceilings: T-bar tiles or glue-on boardsStart from the existing ceiling; check NRC by test mounting, plenum depth, humidity and cleaning.
- Sound transmission and flankingSound travels through the wall, leaks and flanking paths such as ceilings, floors and ducts, so site results are usually below lab ratings.
- Keeping outside noise out of a bedroomRoad and aircraft noise gets in via windows, doors and leaks first — fix the weakest point first
- Reducing rain noise on a metal roofDamp the roof sheet and build an airtight, insulated ceiling
- Footsteps and impact noise from the floor aboveImpact sound travels through the structure: treat the floor above first; a decoupled insulated ceiling helps partly from below.
- Soundproofing a ceiling against the floor aboveDecoupled frame, heavy solid boards, cavity insulation and sealed penetrations such as downlights - with flanking as the limit.
- Acoustic foam panelsOpen-cell foam cuts echo; thickness sets the frequency range; it is not sound insulation — ask for fire test data.
- Clear speech in classrooms and open officesControl reverberation and background noise together: ceiling, rear wall, side walls, then the noise sources.
- How to choose sound-absorbing materialCheck NRC and band values, thickness and air gap, area and placement, facing — and fire data in the datasheet.
- Sound leaking through doorsThe door is usually the weak point: seal the gaps first, then the leaf, then a sound lock
- Reducing plant-room, pump and generator noiseFour measures together: block, absorb inside, isolate vibration and treat ventilation openings.
- Mass law and decoupling: why double-leaf walls workDoubling mass gives only about 6 dB; a decoupled, deep, insulated and sealed double-leaf wall gives far more.
HVAC and ductwork 5 articles
- Why AC ducts need insulationLess lost cooling, no dripping cold ducts, lower energy use — and less noise with internal liner.
- Duct wrap vs duct linerWrap outside for heat and condensation; liner inside also cuts duct noise but must resist airflow.
- How to choose duct insulationCheck conditions, humidity, vapour retarder and fire requirements, then pick wrap, liner or flexible duct.
- What is insulated flexible duct?Factory-insulated bendable duct for short runs to diffusers; bends and sag raise pressure loss.
- Insulating kitchen exhaust and hot exhaust ductsNon-combustible stone wool, pins and metal jacketing; a fire-rated duct is a tested system.
Pipe insulation 5 articles
- Why AC and chilled-water pipes dripSurface below dew point, gaps, crushed insulation, open joints — find the cause and fix it properly.
- How to choose pipe insulationCold or hot line, service temperature, bore size, designed thickness, material and outdoor protection.
- Pipe sizes: NPS, inches and actual ODA pipe's name is not its measured size: choose insulation by actual OD and bore.
- Choosing insulation for hot-water and steam pipesCheck pipe temperature first, pick the form that suits the pipe, then jacket it against water.
- Elastomeric pipe insulation outdoors: UV protectionOutdoors, finish it as that product's maker specifies, and glue every seam first.
Industrial and high temperature 4 articles
- Corrosion under insulation (CUI)Hidden corrosion from water trapped under insulation — limited by coatings, low-absorption insulation, jacketing and inspection.
- Slab, blanket, wired mat or pipe section?Choose the form by surface shape, then the grade by maximum service temperature.
- Insulating tanks, boilers, ovens and hot ductsSlabs on pins for flat walls, wired mats for curved or vibrating surfaces, staggered layers, ceramic fibre beyond stone wool's range.
- Choosing high-temperature insulationCheck real maximum temperature, form, chloride limits for stainless steel and cladding; specialists calculate thickness.
Fire protection 3 articles
- Insulation in fire: foams vs mineral woolMineral wool is not fuel; foams can burn even with flame retardants — and each test measures something different.
- Reaction to fire vs non-combustible vs fire resistanceThree different questions: how much a material feeds fire, whether it is fuel, and how long a system holds fire back.
- Stone wool in passive fire protectionStone wool seals gaps to keep fire compartments intact, but the fire rating belongs to the tested, properly installed system.
Materials 12 articles
- What is elastomeric foam insulation?Closed-cell synthetic-rubber foam (NBR or EPDM) for chilled-water and refrigerant pipes.
- What is glass wool?Glass wool is spun from molten glass; rolls, boards and pipe sections for roofs, ceilings, ducts, pipes and acoustics.
- Is stone wool dangerous?Stone wool is not asbestos — and how to handle it safely
- What is PE foam insulation?Closed-cell polyethylene foam, often film/foil-faced, for roofs and ceilings; fire results vary by product.
- What is stone wool?Stone wool is spun from molten rock, used for thermal insulation, wall acoustics, hot industrial work and fire-protection systems.
- Closed-cell vs fibrous insulationClosed cell resists vapour in its body; fibrous absorbs sound and has high-temperature grades.
- What is ceramic fibre?Fibre insulation for very hot industrial work — not building insulation; install with PPE per the SDS.
- Choosing a stone-wool slab grade (40-100 kg/m³)Density changes rigidity and weight more than NRC - choose by job: cavity, exposed absorber, roof or high temperature.
- What is calcium silicate insulation?Rigid insulation for hot pipes and equipment: better in compression than fibre, but must be kept dry.
- What is mineral fibre board?A porous acoustic board for ceilings and walls: cuts echo, but is sensitive to humidity and paint.
- What is polyester fibre insulation?Heat-bonded PET fibre: soft and itch-free for cavities and absorbers — ask about temperature and fire data.
- Insulation facings and what each is forFoil and FSK/FRK control vapour; glass tissue and cloth pass sound; perforated foil gives a smooth absorbing face.
Comparisons 2 articles
Installation and use 4 articles
- Gaps and compression in insulationInsulation performs when it covers fully, at full thickness
- Why insulation joints and sealing matterOpen joints cause condensation even with enough thickness. Use the maker's adhesive and tape; don't crush at hangers.
- Pins, adhesive and foil tape for fixing insulationPins carry weight, adhesive bonds, foil tape seals: match each to the insulation and temperature.
- Before you insulate a drywall partitionFill the cavity without over-packing, seal perimeters and outlets, and follow a documented wall system.
Terms and values 14 articles
- What is NRC?What the number tells you — and what it does not
- What are STC and Rw?A rating for the whole wall, not for one material
- Dew point and condensationSurfaces colder than the dew point collect water; the higher the humidity, the closer the dew point to air temperature.
- Thermal conductivity (λ, k-value)Low λ means the material conducts little heat — real results depend on thickness and installation
- Vapour barrier / vapour retarderThe vapour-resisting layer on cold insulation works only when continuous, with every joint, tear and penetration sealed.
- Insulation densityDenser is not always better — compare the property you need
- Thermal resistance (R-value)R = thickness ÷ λ; higher is better — and never mix SI and imperial units
- U-value vs R-valueU is heat through a whole wall or roof — lower is better, = 1 ÷ total R
- Service temperatureThe surface-temperature range in which insulation still performs as stated — not melting point or a fire result.
- Sound absorption coefficient (α)α is the share of sound not reflected, per frequency; NRC, SAA and αw summarise it; thickness and air gap drive the bass.
- Personnel protection and surface temperatureInsulating so the outer surface will not burn on contact; the limit comes from the project, thickness is calculated.
- Moisture in insulation: absorption, sorption and repellencyThree values for water in different forms; wet insulation insulates less, and repellency does not replace a vapour barrier.
- Emissivity and the reflectivity of foilFoil emits and absorbs little radiant heat — if it is clean and faces an air space. It is not an R-value.
- What is a thermal bridge?Spots where heat bypasses insulation — purlins, steel framing, screws, gaps — reduced by continuous insulation.
Technical terms
Short definitions of the terms and values you meet in product datasheets
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