Insulation & Membranes
347 sources in the library on insulation & membranes, 40 on this page cited in a published note. Each one says what the document covers and what it is good for. Name a source to see which document it is and where to read it. One at a time. Page 2 of 9.
- strong RN-X4CJG1 cited
BSI
the withdrawn guide to assessing a cavity wall's suitability for filling, which Approved Document C still names
Cited in Cavity Wall Insulation Materials Compared, Wall Insulation Materials: Cavity, Internal & External.
- strong RN-9A1H9G cited
BSI
The standard that produces the Euroclass letter, and the one regulation 7(2) of the Building Regulations names by title and ISBN when it requires external wall materials on a relevant building to be Class A2-s1, d0 or A1. Published 31 Jan 2019 and Current. Part 1 provides the reaction to fire classification procedure for all construction products, including products incorporated within building elements, with the sole exception of power, control and communication cables which are classified under EN 13501-6. Products are considered in relation to their end-use application, which is why an insulation board or cladding panel cannot carry a meaningful Euroclass in the abstract: the classification attaches to the product as used in a stated build-up. This is the reference for reading the suffixes as well as the letter, s for smoke production and d for flaming droplets.
Cited in Cladding and Render: The Complete UK Guide (2026), PIR vs Mineral Wool Insulation Compared.
- strong RN-2T8K9A cited
BSI
the laboratory method for measuring the sound insulation of a building element, which is where a product's Rw comes from
Cited in Acoustic Insulation for Floors & Walls.
- strong RN-VLMNAU cited
BSI
the standard the driving rain index behind the UK exposure map is calculated to, from hourly wind and rain data
- strong RN-24Q969 cited
BSI
the field method for measuring sound insulation in a finished building, which is what a Part E pre-completion test runs to
Cited in Acoustic Insulation for Floors & Walls.
- strong RN-SI9E6S cited
BSI
the standard that rates airborne sound insulation into a single figure, which is where Rw and the C and Ctr spectrum adaptation terms come from
Cited in Acoustic Insulation for Floors & Walls.
- strong RN-F2ZMFF cited
BSI
the standard that rates impact sound insulation into a single figure
Cited in Acoustic Insulation for Floors & Walls.
- strong RN-DCE677 cited
BSI
the combined retrofit specification that publicly funded energy efficiency work has to be installed under
Cited in Cavity Wall Insulation Materials Compared, External Wall Insulation (EWI) Systems & Finishes, Insulation Grants 2026: ECO4, GBIS & What You Can Get, Loft & Roll Insulation: Types, Depth & U-values and 1 more.
- strong RN-L1P8GV cited
BSI (British Standards Institution)
The product standard for rock and glass mineral wool, the material behind loft roll, cavity batts and acoustic quilt. Published 28 Feb 2013, current but under review, and carries Designated status meaning it is a designated standard for UKCA marking. It specifies requirements for factory made mineral wool products with or without facings or coatings used for the thermal insulation of buildings, manufactured as mat blankets, boards or slabs, and covers product characteristics, testing, evaluation of conformity, marking and labelling. Three limits are worth citing: it does not specify what level of any property a product must reach for a particular application, which is set by regulations instead; products with a declared thermal resistance below 0.25 m2K/W or a declared thermal conductivity above 0.060 W/mK at 10 degrees C fall outside it; and it excludes in situ insulation, covered instead by EN 14064 parts 1 and 2, and building equipment insulation, covered by EN 14303. It also states that the performance of a system incorporating these products is not covered, which is why a full wall build-up needs its own assessment.
Cited in Cavity Wall Insulation Materials Compared, Floor Insulation Materials & Build-ups, Loft & Roll Insulation: Types, Depth & U-values, PIR vs Mineral Wool Insulation Compared and 1 more.
- strong RN-21YSR6 cited
BSI (British Standards Institution)
The product standard for EPS, the white bead board used for most external wall insulation systems and under many floor slabs. Published 28 Feb 2013, current but under review. It specifies requirements for factory made expanded polystyrene products with or without rigid or flexible facings or coatings used for the thermal insulation of buildings, made as boards, rolls or other preformed shapes including tapered, tongue and groove, shiplap and profiled, and notes the same products are used for sound insulation and in prefabricated systems and composite panels. It sets classes of dimensional tolerance for length, width, thickness, squareness and flatness, the EPS designation code, sampling and conditioning for thermal tests, and the Assessment and Verification of Constancy of Performance regime of type testing plus factory production control. Products with a declared thermal resistance below 0.25 m2K/W or a declared thermal conductivity above 0.060 W/mK at 10 degrees C are outside its scope, as are in situ products, building equipment and industrial insulation, civil engineering applications and beam and block floor systems.
Cited in Cavity Wall Insulation Materials Compared, EPS vs XPS Insulation: Which & Where, Floor Insulation Materials & Build-ups, Wall Insulation Materials: Cavity, Internal & External.
- strong RN-W6XBQJ cited
BSI (British Standards Institution)
The product standard for XPS, the coloured closed cell board used below screeds, in inverted roofs and where water resistance matters. Published 28 Feb 2013, current but under review, with Designated status for UKCA marking. It specifies requirements for factory made extruded polystyrene foam products with or without facings or coatings used for thermal insulation of buildings, manufactured as boards including special edge and surface treatments such as tongue and groove and shiplap, and also used in prefabricated thermal insulating systems and composite panels. As with the other 131xx standards it does not set the property level a product must reach for a given application, which is left to regulations. Products with a declared thermal resistance below 0.25 m2K/W or declared thermal conductivity above 0.060 W/mK at 10 degrees C are excluded, as are in situ products, building equipment and industrial insulation covered by EN 14307, and civil engineering applications covered by EN 14934.
Cited in EPS vs XPS Insulation: Which & Where.
- strong RN-03453V cited
BSI (British Standards Institution)
The product standard for PIR and PUR boards, the rigid foil faced insulation sold under brand names such as Kingspan and Celotex. Published 28 Feb 2013, listed as Current with Designated status for UKCA marking. It specifies requirements for factory made rigid polyurethane foam products with or without facings or coatings used for the thermal insulation of buildings, made in board form, and the page states explicitly that PU includes both PIR and PUR products, which settles the common confusion about whether PIR has its own standard. It covers multi-layered PU insulation products, product characteristics, testing, evaluation of conformity, marking and labelling, dimensional tolerance classes for length, width, thickness, squareness and flatness, the designation code, and the AVCP regime of type testing plus factory production control. Products with a declared thermal resistance below 0.25 m2K/W or declared thermal conductivity above 0.060 W/mK at 10 degrees C are excluded, as are in situ insulation products and insulation of building equipment and industrial installations.
Cited in Floor Insulation Materials & Build-ups, PIR vs Mineral Wool Insulation Compared, Wall Insulation Materials: Cavity, Internal & External.
- strong RN-TRC3IR cited
BSI (British Standards Institution)
The product standard for wall breather membranes, the sheet that sits behind timber, fibre cement or rainscreen cladding. Published 31 May 2014 and Current. Part 2 of the BS EN 13859 series specifies the characteristics of flexible sheets used as underlays for walls, that is behind outside wall coverings, in order to avoid the penetration of wind and water from outside. It is the wall counterpart to Part 1, which covers underlays for discontinuous roofing, so a note distinguishing a roofing breather membrane from a wall breather membrane can cite one part each rather than treating them as interchangeable products.
- strong RN-3B3DX9 cited
BSI (British Standards Institution)
STATUS: CURRENT, and it is the replacement for a standard the notes still cite. BS EN ISO 16535:2019 was published 31 July 2019 and expressly supersedes BS EN 12087:2013, which is WITHDRAWN. It specifies the equipment and procedure for determining the long term water absorption of thermal insulating products, giving two methods: method 1 partial immersion and method 2 total immersion. This is the test behind the WL(T) declared value used to compare rigid boards for below ground, inverted roof and perimeter use, which is why extruded polystyrene (XPS) is specified below damp proof level rather than expanded polystyrene or unfaced PIR. Any note citing BS EN 12087 for water absorption of insulation should be corrected to BS EN ISO 16535. Catalogue page confirms number, title, date, status, the supersession of BS EN 12087:2013 and the two methods; the procedure detail is paywalled.
Cited in EPS vs XPS Insulation: Which & Where.
- strong RN-3XCF26 cited
Business Companion (Chartered Trading Standards Institute)
Trading Standards' Business Companion guidance for spray foam installers says the product must hold an independent test certificate from a body such as the BBA or Kiwa.
Cited in Spray Foam Insulation: Costs, Risks & Mortgage Issues.
- strong RN-9K9QLS cited
Jablite
Jablite technical data sheet for its Jabfloor EPS floor insulation laid over a slab under a screed. It lists each grade with its thermal conductivity and compressive strength, and the building type each grade is meant for, with Jabfloor 70 for domestic floors.
Cited in EPS vs XPS Insulation: Which & Where.
- strong RN-SDESVT cited
Royal Institution of Chartered Surveyors
The RICS consumer guide on spray foam notes Trading Standards and media concern about cold calls and unsolicited offers to sell or remove spray foam.
Cited in Internal Wall Insulation: Costs & Methods, Spray Foam Insulation: Costs, Risks & Mortgage Issues, Vaulted Ceilings: Cost & How to Open Up a Ceiling.
- strong RN-ZZXPVK cited
The Law Society
The Law Society's TA6 explanatory notes tell sellers that buyers can rely on their answers and may claim compensation for misleading information.
Cited in Spray Foam Insulation: Costs, Risks & Mortgage Issues.
- strong RN-BNGAID cited
United Kingdom Accreditation Service
The live UKAS register of accredited bodies currently under sanction. It records the British Board of Agrement under imposed suspension from 26 February 2026 across all four of its accreditations: ISO/IEC 17065 product certification and ISO/IEC 17021 management systems under reference 0113, ISO/IEC 17020 inspection under 4345, and ISO/IEC 17025 testing under 0357. This is the page to check before repeating any advice that treats a BBA certificate as accredited third party assurance.
Cited in Breathable Membranes for Roofs & Walls, Damp Proof Membranes (DPM) & DPC: Types & Installation, EPC Ratings Explained & How to Improve Yours, External Wall Insulation (EWI) Systems & Finishes and 4 more.
- strong RN-TUN04M cited
United Kingdom Accreditation Service
UKAS's statement confirms it suspended all scopes of the BBA's accreditation on 26 February 2026 and that the BBA cannot issue new accredited certificates meanwhile.
Cited in Brick Slips & Brick Cladding Systems, Cavity Wall Insulation Materials Compared, Spray Foam Insulation: Costs, Risks & Mortgage Issues.
- good RN-Q23GSP cited
British Plastics Federation
The British Plastics Federation's EPS page explains how polystyrene beads are expanded with steam and then moulded, which is how EPS boards are made.
Cited in EPS vs XPS Insulation: Which & Where.
- good RN-2PPZEW cited
Cavity Insulation Guarantee Agency
CIGA is the independent agency issuing guarantees for cavity wall insulation across the UK and the Channel Islands. It provides independent 25 year guarantees for cavity wall insulation fitted by CIGA-registered installers, and the guarantee is only valid where the installer was registered at the time of the work, so a homeowner should verify registration before the job rather than after. Guarantee holders can check cover, raise a concern through the register-a-concern route, or use the formal complaints process for a dispute; contact is 01525 853300 or info@ciga.co.uk. This is the source to cite when a note tells a reader how to find out whether existing cavity fill is guaranteed.
Cited in Insulation: The Complete Guide.
- good RN-0YCUN4 cited
INCA (Insulated Render and Cladding Association)
INCA's page on how external wall insulation sits inside the PAS 2035 retrofit framework. It defines PAS 2035 as a Publicly Available Specification designed to provide a clear retrofit standards framework for the installation of energy efficiency measures, built to raise standards and consistency in both the design and the installation of those measures and to ensure they are appropriate for the property and will perform as expected. It points to PAS 2035/2030+A1 2022 as the applicable version, and it flags the point most often missed on an EWI retrofit: the requirements for air tightness testing and for ventilation measures that come with wrapping a house. It also links the Retrofit Academy guide PAS 2035 Ventilation for Domestic Retrofit. Use it to explain why a grant funded EWI job carries assessment and ventilation obligations that a straight private render job does not.
- good RN-X5I9PN cited
Liquid Roofing and Waterproofing Association
A trade association guidance note that summarises BS 6229: waterproofing upstands should rise at least 150 mm above the finished roof surface.
Cited in Insulating & Repairing a Bay Window Roof.
- good RN-HHDQ4R cited
Property Care Association
The PCA's homeowner position on spray foam. Closed-cell foam can create a barrier that traps moisture within the roof cavity, causing condensation build-up in cold weather and potentially timber rot and decay, and its air-sealing can restrict roof space ventilation so a lack of airflow makes the moisture problem worse. Because the foam completely obscures trusses, rafters and sheathing, surveyors cannot visually inspect the timber. The PCA confirms the market consequence directly: concerns raised by valuation surveyors have in recent years concerned lenders, insurers and the wider surveying profession, affecting the valuation of some homes and leading certain mortgage companies to refuse to lend. An industry working group produced new inspection protocols for valuation surveyors, and the PCA points homeowners to designated spray foam assessors.
Cited in Insulation: The Complete Guide.
- fair RN-54KWR6 cited
Energy Saving Trust
How to identify a cavity wall and what filling it costs. About 33% of all heat lost from an uninsulated home escapes through the walls. Houses built after the 1920s usually have cavity walls; pre 1920 houses are usually solid; houses from the 1990s onwards usually already have wall insulation. Identification: cavity walls show an even stretcher bond with all bricks laid lengthways, solid walls show an alternating pattern with header ends visible; a brick wall 260mm to 350mm thick is likely a cavity wall, narrower is likely solid, stone walls are solid up to about 500mm thick and earth walls run 300mm to over a metre. Typical installed cost around £2,200 in Great Britain and around £1,000 in Northern Ireland, with payback usually five years or less. Unsuitable where the wall is exposed to extreme weather or flooding, in poor condition, at risk of overheating, or where the cavity is narrower than 50mm. External repairs to brickwork, pointing, roofs, gutters and downpipes must be completed first or damp can be trapped. Underfloor grilles, airbricks, wall vents and trickle vents must not be blocked. Post installation damp is chased through the installer, then the Cavity Insulation Guarantee Agency guarantee or an independent insurance backed guarantee.
Cited in Cavity Wall Insulation Materials Compared, EPC Ratings Explained & How to Improve Yours, Home Energy Audit: DIY Steps, Renovating a 1930s House and 3 more.
- fair RN-9FOXX3 cited
Energy Saving Trust
Floor insulation performance targets, savings and cost. Target U-values: 0.25 W/m2K or lower in England, Wales and Northern Ireland, and 0.18 W/m2K or lower in Scotland, achieved with at least 70mm of high performance rigid foam or around 150mm of mineral wool depending on floor type and construction. Replacing 50% or more of a floor triggers the duty to insulate to those standards even if insulation was not in the original plan. Insulating under the ground floor boards saves about £55 a year in Great Britain and £70 in Northern Ireland, rising to up to £85 in GB and £120 in NI for a detached house, and cuts about 180kg of carbon in GB and 260kg in NI. A typical suspended timber floor installation costs £1,400 to £2,500 by house type, and solid floor insulation costs considerably more. Suspended timber floors are typical of homes built between the 1850s and the 1950s, identified by airbricks below floor level; solid concrete ground floors are common from the 1950s onwards, and floors built since the early 2000s are usually already insulated.
Cited in Home Energy Audit: DIY Steps, Insulation: The Complete Guide, Underfloor Insulation: Suspended & Solid.
- fair RN-RV8Z6H cited
Energy Saving Trust
Solid wall insulation costs and the quality problem. Typical installation £12,000 to £15,000, split as around £15,000 for external wall insulation and around £12,000 for internal. Around 33% of the heat lost from an uninsulated home goes through the walls. Homes built before 1920 are more likely to have solid walls, of brick, stone, earth or timber frame with panels. A registered installer should guarantee the work for 25 years, and any TrustMark solid wall insulation company offers a 25 year guarantee backed either by an insurer or through the Solid Wall Insulation Guarantee Agency. Records that in October 2025 the National Audit Office reported on quality failures in wall insulation under government schemes, and that 98% of homes fitted with external wall insulation under ECO4 and the Great British Insulation Scheme have problems needing fixing, with affected households sent an Ofgem letter carrying a Unique Measure Reference Number in early 2026 and a remediation line on 0333 555 1234 option 1.
Cited in Damp Walls: Diagnosing the Type, DPC Injection vs Membrane for Rising Damp, EPC Ratings Explained & How to Improve Yours, Insulation: The Complete Guide and 4 more.
- fair RN-Q9LHGH cited
HomeOwners Alliance
The HomeOwners Alliance reports its research with the BBC finding only 25% of mortgage lenders and no equity release providers would lend on homes with retrofitted spray foam.
Cited in Spray Foam Insulation: Costs, Risks & Mortgage Issues.
- fair RN-Q66G5M cited
HomeOwners Alliance
The spray foam roof insulation problem set out with numbers. The Property Care Association estimates as many as 250,000 UK homes have spray foam in the loft, after roughly 30 years on the market and a decade of grant driven growth. Lenders may decline or downvalue a property with it. A specialist surveyor's inspection of the roof, structure and paperwork costs £500 to £700. Removal runs about £40 per m2 per Checkatrade, before skips and disposal; a reader case is quoted where removal of open cell foam was priced at £17,000 against an original £12,000 installation. Warns about rogue removal firms and states the code expectation of a cooling off period of at least 14 days during which no install or removal should take place.
Cited in Spray Foam Insulation: Costs, Risks & Mortgage Issues.
- fair RN-FV16LZ cited
Insulation Manufacturers Association
The IMA's May 2023 industry code of practice for spray foam in domestic roofs, requiring manufacturer-trained and approved installers, surveys and a homeowner pack.
Cited in Spray Foam Insulation: Costs, Risks & Mortgage Issues.
- fair RN-NX3OVT cited
Roof Tile Association
The Roof Tile Association's installation guidance for underlay, written to BS 5534. It gives the 150 mm unsupported head lap over 15 degrees and the 100 mm minimum side lap.
- supplier figure RN-VDPI65 cited
A. Proctor Group
A membrane maker's technical article setting out the BS 5250 definitions: an LR roof underlay has an Sd no greater than 0.05 m (0.25 MN·s/g).
Cited in Breathable Membranes for Roofs & Walls.
- supplier figure RN-PFIU0Z cited
A. Proctor Group
Maker's product page for a reinforced polythene vapour control layer, declaring its vapour resistance as 533 MN·s/g, which is roughly an Sd of 100 m.
Cited in Breathable Membranes for Roofs & Walls.
- supplier figure RN-UUKIJP cited
A. Proctor Group
A. Proctor Group's UK installation guide for its vapour control layers sets minimum 150 mm vertical and horizontal overlaps, sealed with its tape.
- supplier figure RN-5B0GTS cited
B&Q
B&Q product page for Jablite 100 mm EPS insulation board, 2400 x 1200 mm, priced at £36 including VAT and shown as £12.50 per square metre.
Cited in Insulation: The Complete Guide.
- supplier figure RN-Q3I274 cited
Builder Depot
Builder Depot's product page for a 100 mm EcoTherm Eco-Versal PIR board, 2400 x 1200 mm, at £45.55 including VAT, or £15.82 per m².
Cited in PIR vs Mineral Wool Insulation Compared.
- supplier figure RN-HRZU4W cited
Builder Depot
Builder Depot's product page for a 2.88 m² pack of 100 mm Rockwool RWA45 stone wool slab (0.035 W/mK), at £33.47 including VAT, or £11.62 per m².
Cited in PIR vs Mineral Wool Insulation Compared.
- supplier figure RN-A6F1GF cited
Builder Depot
Builder Depot's product page for a 150 mm EcoTherm Eco-Versal PIR board (thermal conductivity 0.022 W/mK), at £78.58 including VAT, or £27.29 per m².
Cited in PIR vs Mineral Wool Insulation Compared.
- supplier figure RN-Q0X1Q7 cited
EcoTherm Insulation (Kingspan Insulation Ltd)
Thermal laminate: PIR core bonded to 12.5 mm Gyproc Type A plasterboard to EN 13950: 2014. Insulation core lambda 0.022 W/mK; plasterboard component lambda 0.19 W/mK. Product thicknesses 37.5 to 82.5 mm (25 to 70 mm of insulation plus 12.5 mm board). Published R-values and typical U-values on a 215 mm dense blockwork wall with 10 mm polymer render: 25 mm insulation R 1.10, U 0.57 battens / 0.56 dot and dab; 30 mm R 1.35, 0.51 / 0.50; 40 mm R 1.80, 0.42 / 0.40; 50 mm R 2.25, 0.36 / 0.34; 60 mm R 2.70, 0.32 / 0.30; 70 mm R 3.15, 0.28 / 0.26 W/m2K. Fire: Eco-Liner achieves European Classification (Euroclass) B-s1,d0 when classified to BS EN 13501-1: 2018, supported by test reports WF 546613 (EN 13823) and WF 516756 (EN ISO 11925-2).