RenovationNotes

References

Insulation & Membranes

273 sources in the library on insulation & membranes, 6 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 7.

  1. supplier figure RN-CPJNFR cited

    Builder Depot Ltd

    the retail price Builder Depot Ltd publishes for Loft Insulation, Builder Depot, which is the supply figure the cost book records for this item

    Cited in Cavity Wall Insulation Materials Compared, How to Insulate Garage, Loft & Roll Insulation: Types, Depth & U-values, Multifoil & Reflective Insulation: Does It Work? and 3 more.

  2. 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).

    Cited in Internal Wall Insulation: Costs & Methods.

  3. supplier figure RN-2DAE36 cited

    Lawsons (Whetstone) Ltd

    the retail price Lawsons (Whetstone) Ltd publishes for PIR Insulation, which is the supply figure the cost book records for this item

    Cited in Builders' Merchant vs DIY Store: Which Is Cheaper?, How to Insulate A Vaulted Ceiling In 5 Steps, How to Insulate Garage, Insulation: The Complete Guide and 1 more.

  4. supplier figure RN-B3Z3CL cited

    Screwfix

    the retail price Screwfix publishes for essentials economy pipe insulation 15mm x 13mm x 1m, which is the supply figure the cost book records for this item

    Cited in How to Box In Pipes & Boilers.

  5. supplier figure RN-MBVS6T cited

    Selco Builders Warehouse

    the retail price Selco Builders Warehouse publishes for Jabfloor 70 Floor Insulation 2400 x 1200 x 100mm, which is the supply figure the cost book records for this item

    Cited in Floor Insulation Materials & Build-ups.

  6. supplier figure RN-5SDEMT cited

    SOPREMA UK (Celotex)

    Thermal laminate: rigid PIR core bonded to 12.5 mm tapered edge plasterboard, boards 2400 x 1200 mm. Declared thermal conductivity of the PIR core 0.022 W/mK. Overall thickness range 37.5 mm to 77.5 mm (PIR 25 mm to 65 mm plus 12.5 mm board). BBA Certificate 25/7366 for internal wall dry lining and pitched roof ceiling applications. Fire: SOPRATHERM PL4000 achieves a reaction to fire classification of Euroclass B-s1, d0 in accordance with BS EN 13501-1.

    Cited in Internal Wall Insulation: Costs & Methods.

  7. very strong RN-O45LHK

    Department of Finance (Northern Ireland)

    Northern Ireland's insulation numbers, October 2012 guidance to Part F1. Table 2.2 sets limiting U-values in W per square metre kelvin for a new dwelling as an area-weighted average with a maximum at any point: wall 0.30 average and 0.70 maximum, floor 0.25 and 0.70, roof 0.20 and 0.35, party wall 0.20 and 0.70, windows, roof windows, glazed rooflights, curtain walling and pedestrian doors 2.00 and 3.30, with 3.50 for new thermal elements. Table 3.2 sets the U-values for new thermal elements, which is what applies when an existing floor or roof is replaced or newly constructed during a renovation: wall 0.28, pitched roof with insulation at ceiling level 0.16, pitched roof with insulation at rafter level 0.18, flat roof or roof with integral insulation 0.18, floor 0.22, swimming pool basin walls and floor 0.25. Window U-values may be taken as the smaller of the two standard windows in BS EN 14351-1, the standard configuration in BR 443, or the actual unit size and configuration. Consequential improvement duties apply above 1000 square metres total useful floor area, and the 25 per cent of total useful floor area test defines a material change.

  8. very strong RN-6PSUIL

    Department of Finance, Northern Ireland (Building Control NI)

    The Northern Ireland U-value standards, which differ from England's Approved Document L and are the figures to quote for an NI reader. Table 2.2 gives limiting U-values for new dwellings in W/m2K as area-weighted averages: wall 0.18, floor 0.18, roof 0.16, party wall 0.00, and windows, roof windows, glazed rooflights, curtain walling and pedestrian doors 1.40. Column (b) sets the maximum U-value at any point: 0.60 for wall, floor and party wall, 0.30 for roof and 3.00 for windows and doors. Where space heating is underfloor heating the maximum floor U-value tightens to 0.15 W/m2K, and that 0.15 still applies even under the whole-building trade-off route in paragraph 2.44. Table 3.2, for new thermal elements in existing dwellings, gives wall 0.28, pitched roof with insulation at ceiling level 0.16, pitched roof with insulation at rafter level 0.18, flat roof or roof with integral insulation 0.18, floor 0.22 and swimming pool basin 0.25. Maximum permissible air permeability is 10 m3/(h.m2) at 50 Pa, with 5 or less expected in practice, and below 3 the booklet says alternatives to natural ventilation should be considered. Roof window and rooflight U-values are quoted as assessed in the vertical position and must be adjusted in accordance with BR 443 where assessed in another plane. Regulation 43 requires that where renovation of a thermal element amounts to more than 50 per cent of its surface area, the whole element is brought up to standard.

  9. very strong RN-S4JZCY

    Department of Finance, Northern Ireland (Building Control NI)

    Northern Ireland's ventilation guidance, the devolved counterpart to Approved Document F, and a clean source for extract rates because its Table 2.1 sets them out room by room. Intermittent extract minimum rates: kitchen 30 litres per second adjacent to the hob or 60 litres per second elsewhere, utility room 30 litres per second, bathroom 15 litres per second, sanitary accommodation 6 litres per second. Continuous extract minimum high rates: kitchen 13 litres per second, utility room 8, bathroom 8, sanitary accommodation 6. The whole-dwelling ventilation rate should not be less than 0.3 litres per second per square metre of internal floor area, and where a greater level of occupancy is expected an extra 4 litres per second per occupant should be added. It describes System 1, background ventilators with intermittent extract fans, as the common domestic strategy. The 30 versus 60 litres per second split is the figure that decides whether a cooker hood can sit above the hob or must be sized up when placed away from it, for example over an island.

  10. very strong RN-VIHNAO

    Home Energy Scotland (Energy Saving Trust, funded by the Scottish Government)

    Scotland's own funding route for heat pumps and insulation, which replaces rather than supplements the England and Wales Boiler Upgrade Scheme, so a Scottish reader must be pointed here. Funded by the Scottish Government, it gives homeowners a grant, an interest-free loan, or both. For clean heating systems such as heat pumps and heat network connections the grant is up to 7,500 pounds with a further 7,500 pounds available as an optional interest-free loan. For energy efficiency measures such as insulation the grant covers up to 75 per cent of the combined cost of measures to a maximum of 7,500 pounds, with the remainder available as an interest-free loan. A rural and island uplift of 1,500 pounds applies to both the heating and the energy efficiency grants, so a rural household can claim up to 18,000 pounds in grant funding. Per-measure grant caps are: air, ground or water source heat pumps and heat network connections 7,500 pounds; wood fuelled biomass boilers and eligible stoves 7,500 pounds; solid wall insulation, external or internal, 7,500 pounds; flat roof or room-in-roof insulation 3,000 pounds; loft, cavity and underfloor insulation 1,500 pounds; high heat retention storage heaters 2,500 pounds. Solar thermal (5,000 pounds loan), hybrid solar PV and water heating (5,000 pounds loan), wind turbine and hydro turbine (2,500 pounds loan each), insulated doors and warm air units are loan only with no grant. Eligibility does not depend on receiving benefits, but the property must be an existing home in Scotland that the applicant owns and occupies as their only or primary private residence. Only heat pumps providing 100 per cent of heating and hot water qualify, and hybrid heat pumps are not eligible.

  11. very strong RN-JHFWQB

    World Health Organization Regional Office for Europe

    Published 15 October 2009, ISBN 9789289041737, the health-based benchmark for night-time noise that a soundproofing or acoustic glazing note can cite for what level of quiet is worth achieving. Using Lnight,outside as defined in the Environmental Noise Directive 2002/49/EC, it sets an Lnight,outside of 40 dB as the target of the night noise guideline to protect the public including the most vulnerable groups, named as children, the chronically ill and the elderly. It recommends an Lnight,outside of 55 dB as an interim target for countries that cannot achieve the guideline in the short term and adopt a stepwise approach. The guidelines were agreed by a working group of experts with industry, government and non-governmental stakeholders in December 2006, and extend and update the WHO Guidelines for community noise of 1999.

  12. very strong RN-R54RCK

    Department for Business and Trade

    Published 31 March 2026, last updated 21 August 2026, and applying to England, Scotland and Wales. States that the UK continues to recognise the CE marking alongside or in place of the UKCA marking for the Great Britain market under the Product Safety and Metrology (Amendment) Regulations 2024, so a CE marked product remains lawful to place on the GB market and manufacturers may choose either route. Sets out the UKCA and CE regimes spanning over 20 product types, and the duties of each economic operator: the manufacturer designs and marks the product, applies identification details (name, trade name or trademark and postal address) and retains the technical documentation. Northern Ireland uses CE or CE and UKNI marking instead, and the UKCA marking does not apply in Guernsey, Jersey, the Isle of Man or the British Overseas Territories.

  13. very strong RN-C20YEY

    Department for Energy Security and Net Zero

    A closed scheme that still binds new owners, which is a trap for anyone buying a property to renovate. The Green Deal is closed to new applicants, but where a property carries a Green Deal loan the liability travels with the property: whoever moves in is responsible for repaying it, through a charge added to the electricity bill, and can change electricity supplier only to one participating in the scheme. A seller or landlord is legally required to tell a buyer or tenant that a Green Deal loan exists, that they will be responsible for it, and to show them the Energy Performance Certificate before they move in; the EPC states what improvements were made and how much remains to be repaid. Early repayment is possible but may attract extra costs, notified by the company managing the loan. Complaints go to the Green Deal provider first, whose details are on the EPC, or to the DESNZ Green Deal team if the provider has ceased trading; if unresolved within 8 weeks the complaint goes to the Financial Ombudsman Service for mis-selling and other financial issues, or to the Energy Ombudsman for poor installation work or non-disclosure by a seller or landlord.

  14. very strong RN-8XFMI0

    Department of Finance (Northern Ireland)

    The Northern Ireland index of technical booklets, which take the place of England's Approved Documents under the Building Regulations (Northern Ireland) 2012. Current editions: B materials and workmanship (July 2013), C site preparation and resistance to contaminants and moisture (October 2012), D structure (October 2012), E fire safety (October 2012), F1 conservation of fuel and power in dwellings and F2 in other buildings (both June 2022), G resistance to the passage of sound (October 2012), H stairs, ramps, guarding and protection from impact (October 2012), J solid waste (October 2012), K ventilation (October 2012), L combustion appliances and fuel storage (October 2012), M physical infrastructure for high-speed communications networks (January 2017), N drainage (October 2012), P sanitary appliances, unvented hot water storage and reducing the risk of scalding (October 2012), R access to and use of buildings (October 2012) and V glazing (October 2012). Note for any electrical note: there is no Northern Ireland technical booklet covering electrical safety, so there is no Part P equivalent and no electrical competent person self-certification regime there. Ventilation is Booklet K, drainage Booklet N and glazing Booklet V, not F, H and K as in England.

  15. very strong RN-78SSH6

    Department of Finance (Northern Ireland)

    NORTHERN IRELAND, giving a fourth set of U-values distinct from England, Wales and Scotland. Table 2.2 sets limiting area-weighted average U-values in W/m2.K with a maximum permitted at any point in brackets: wall 0.18 (0.60), floor 0.18 (0.60), roof 0.16 (0.30), party wall 0.00 (0.60), and windows, roof windows, glazed rooflights, curtain walling and pedestrian doors 1.40 (3.00). Where the space heating source is underfloor heating the maximum floor U-value tightens to 0.15. Compare Wales at 0.13 for roofs and Scotland at 0.12, against NI's 0.16. Paragraph 2.43 limits the extent of external doors and glazed openings in a dwelling to no more than 25 per cent of the dwelling's floor area, and the limiting air permeability is 10 m3 per hour per square metre at 50 Pa, looser than the Welsh 8.0. U-values are calculated to BRE Report BR 443. A swimming pool basin must achieve not more than 0.25.

  16. very strong RN-W4V5H5

    GOV.UK

    HUG Phase 2 ran from April 2023 until March 2025, with up to £630 million of grant funding for successful local authorities across the two financial years; local authority applications closed 27 January 2023 after assessment deadlines of 18 November 2022 and 27 January 2023. The page names no successor, so pair it with the Warm Homes: Local Grant page.

  17. very strong RN-NVP3TG

    GOV.UK (Ministry of Housing, Communities and Local Government)

    The consultation and the published government response that set the direction for Parts L, F and O of the Building Regulations, which is what a note should cite when explaining what is coming rather than what applies today. The consultation ran from December 2023 to March 2024 and sought views on changes to the Building Regulations to improve the energy performance and ventilation standards of new homes and buildings, together with a call for evidence on the overheating standard in Part O. The page carries the consultation outcome, the government response document covering changes to Parts L and F and the Part O call for evidence, and the impact assessments. The response states that where relevant the outcomes will be implemented through a statutory instrument and new approved documents, which is the route by which the 2026 editions of Approved Documents L and F were made.

  18. very strong RN-XZVPDF

    Historic Environment Scotland

    The most useful of the HES INFORM guides for a retrofit note, because it addresses the failure mode that insulation guides skip. Published 31 August 2020 by Historic Environment Scotland, INFORM Guide, 2.82 MB PDF, audiences Planners and Owners and Conservation and Heritage enthusiasts. Scope stated on the page: the causes and risks of condensation in traditional buildings, how to identify the source of condensation and how to reduce it, with a PARTICULAR FOCUS ON THE RISK OF INCREASED CONDENSATION AFTER THERMAL IMPROVEMENTS. That last point is the citable one: a public body stating that insulating a traditional building can increase condensation risk, which contradicts the common claim that insulation simply cures damp.

  19. very strong RN-MMEX1T

    Historic Environment Scotland

    A free public-body technical guide on damp in traditional buildings, and the accessible route to heritage-grade damp advice because Historic England blocks scripted fetches. Published 1 July 2007 by Historic Environment Scotland, publication type Technical, Advice and Guidance, INFORM Guide, audiences Planners and Owners and Conservation and Heritage enthusiasts, subjects Architecture and Climate Change, downloadable as a 288 KB PDF from the page. Scope stated on the page: recognising the causes and early signs of damp, and guidance on rectifying damp problems. Use it as the counterweight to damp-proofing sales literature, since HES guidance for solid-walled traditional buildings does not start from the chemical injected damp proof course assumption that dominates UK damp articles. Note the jurisdiction: it is Scottish guidance, so the building science transfers but any regulatory reference does not.

  20. very strong RN-Z55Y2I

    Historic Environment Scotland

    Free HES guidance on how a traditional house was designed to breathe, useful whenever a note explains why blocking air bricks or sealing a chimney causes damp. Published 1 October 2008 by Historic Scotland (now HES), INFORM Guide, 653 KB PDF, audiences Planners and Owners and Conservation and Heritage enthusiasts. Scope stated on the page: the importance of ventilation in a traditionally built structure, then the various ways ventilation is provided, specifically SUB-FLOOR VENTILATION and CHIMNEYS, and issues surrounding masonry walls and plastered surfaces. Cite it alongside Approved Document F when a note covers suspended timber floors, chimney capping or draught-proofing an older house.

  21. very strong RN-2E60JR

    Ministry of Housing, Communities and Local Government

    The shortest Approved Document, covering requirement D1 of Schedule 1 to the Building Regulations 2010: if insulating material is inserted into a cavity in a cavity wall, reasonable precautions must be taken to prevent the subsequent permeation of toxic fumes into any part of the building occupied by people. The stated performance is that formaldehyde fumes given off by urea formaldehyde (UF) foams must not reach occupied parts at an irritant concentration, and paragraph 1.1 permits formaldehyde-emitting insulants only where a continuous barrier minimises the passage of fumes to occupiable parts. Paragraph 1.2 sets five conditions for filling a cavity with UF foam: the inner leaf must be masonry (brick or block); suitability must be assessed beforehand to BS 8208-1:1985; the installer must hold or operate under a current Certificate of Registration of Assessed Capability; the material must comply with BS 5617:1985; and installation must follow BS 5618:1985. The 2010 amendments were regulation renumbering only and the 2013 amendments changed only the materials and workmanship guidance, with no change to Part D of Schedule 1.

  22. very strong RN-0D3FRR

    Ministry of Housing, Communities and Local Government

    The publication page for the conditions a competent person self-certification scheme operator must meet, applying to England, first published 6 June 2012 and last updated 1 April 2016, from which date the conditions bite on any UKAS assessment begun on or after 1 April 2016. Hosts two documents: the main Competent person schemes conditions of authorisation of April 2016, an 8 page PDF of 289 KB, and a separate Building regulations: air tightness testing schemes conditions of authorisation of 5 pages and 141 KB, added 31 July 2014, because air tightness tester schemes carry different requirements from other types of work. Useful for establishing that a competent person scheme is a government-authorised, UKAS-accredited certification body rather than a trade membership list.

  23. very strong RN-GWUUOR

    Ministry of Housing, Communities and Local Government

    The landing page for Approved Document L, Conservation of fuel and power. Volume 1: Dwellings, 2021 edition incorporating 2023 amendments, took effect 15 June 2022, with transitional cover where a building notice or initial notice was given or full plans deposited before 15 June 2022 and the work started before 15 June 2023. A 2026 edition, retitled Approved Document L: Energy and greenhouse gas emissions, Volume 1: Dwellings, is published on the same page alongside Volume 2 for buildings other than dwellings. Volume 1 was last updated 2 February 2023 and the 2023 amendment removed the primary energy factor as a performance standard for district heat networks and community heating.

  24. very strong RN-8Y875H

    Ministry of Housing, Communities and Local Government

    The list of test standards common across product families that UK approved bodies use when assessing construction products, published 27 January 2021 and last updated 21 May 2025, in force from 1 January 2021. Names the specific test methods behind fire performance claims a product data sheet will quote, so a note can verify what a rating actually measures: TS 1187 external fire exposure to roofs; EN ISO 1182 non-combustibility test; EN ISO 1716 gross heat of combustion or calorific value; EN 13823 the single burning item test for building products excluding floorings; EN ISO 11925-2 ignitability under direct flame impingement, the single-flame source test; EN ISO 9239-1 burning behaviour of floorings using a radiant heat source; EN 1365-3 and EN 1365-4 fire resistance of loadbearing beams and columns; EN 1634-1 and EN 1634-3 fire resistance and smoke control for door and shutter assemblies and openable windows; and the EN and ENV 13381 series for applied protection to composite, hollow steel, timber and steel structural members. The latest versions of the standards themselves are on the BSI website.

  25. very strong RN-ZM5DZM

    Ministry of Housing, Communities and Local Government

    The landing page for the 2019 research, published 1 October 2019 and applying to England, hosting the 87 page 3.97 MB report. States the primary aim was to evaluate whether the ventilation provisions recommended in the 2010 edition of Approved Document F provide satisfactory indoor air quality in new homes, with a secondary aim of establishing the extent to which installed systems comply with the minimum ADF provisions. Its headline conclusion is the one to cite: the study found poor indoor air quality in a number of the monitored homes, and failure to meet indoor air quality indicators corresponded in all cases with failure to meet the ADF ventilation recommendations, so the shortfall lay in installation and commissioning rather than in the standard itself.

  26. very strong RN-W3L96O

    Ministry of Housing, Communities and Local Government

    An 87 page field study published 1 October 2019 measuring what installed ventilation actually delivers, and its numbers demolish the assumption that a new or upgraded system performs as designed. Of 25 homes visited with continuous mechanical extract, only one met Approved Document F guidance on both extract fan air flow rates and trickle ventilator provision, with whole dwelling extract flow rates in normal low-rate mode ranging from 85 per cent below to 8 per cent above the recommended rate. Only half the homes met the minimum trickle ventilator areas, ranging from 60 per cent below to 107 per cent above the recommended area. On two of three dMEV development sites trickle ventilators had been fitted in the same rooms as the extract fans, contrary to ADF guidance, which can stop fans drawing air through the whole house. On air quality: 11 per cent of the limited monitoring sample had a room where weekly average relative humidity exceeded the recommended monthly average, always the bedroom, and condensation or mould was reported in each such room; 30 per cent exceeded the derived carbon dioxide guideline in the bedroom; and 60 per cent of the detailed monitoring sample exceeded the ADF total volatile organic compound performance standard. Ventilation was found adequate for nitrogen dioxide and carbon monoxide but not for moisture, body odour and VOCs. Notes that Part F 2010 introduced a legal requirement to test and commission installed fans and for the installer to notify the building control body of commissioning and air flow rates.

  27. very strong RN-XS4MR0

    Ministry of Housing, Communities and Local Government and Office for Product Safety and Standards

    The official list that decides which British and European standards a construction product's declaration of performance must be assessed against, first published 18 December 2020 and last updated 26 September 2025, applying to England, Scotland and Wales. Explains that designated standards support Regulation (EU) No. 305/2011 as amended from time to time, and that together with the horizontal standards on assessment methods they create the common technical language UK approved bodies use when carrying out assessments. Published as a notice of publication dated 26 September 2025, a 51 page PDF, superseding the notice of 1 January 2021 of 53 pages, alongside a consolidated list in ODS format at version 2. This is the reference that turns the standard number cited in a declaration of performance into a check that the right standard was used. A companion page covers horizontal test specifications for construction products.

  28. very strong RN-FSY9SH

    Office for Product Safety and Standards

    The searchable national database a reader can use to check whether a specific building product, appliance or tool has been recalled or flagged, run by the Office for Product Safety and Standards. Holds 3,692 reports at the date checked, filterable by alert type (product safety alert, product safety report, product recall), risk level (serious, high, medium, low, not provided), product category, measure type and date. Relevant product categories for renovation work include Construction products, Gas appliances and components, Electrical appliances and equipment, Lighting equipment, Adaptors, plugs and sockets, Hand tools, Machinery, Lifts, Pressure equipment and vessels, Furniture and Personal protective equipment. Measure types range from warning consumers of the risks and marking the product with warnings, through modification programmes and withdrawal from the market, to recall from end users, destruction of the product, import rejected at border and removal of the listing by the online marketplace. Entries carry a reference number and date, for example Sophie Allport Doorstops and Draught Excluders (2608-0008) recalled 13 August 2026.

  29. very strong RN-VW2AA1

    Scottish Government

    The Scottish rule that explains why boarding out and over-stuffing a loft causes damp. Standard 3.15 requires the building to be designed and constructed so there is no threat to the building or to occupants' health from surface or interstitial condensation. For a cold pitched roof with insulation at ceiling level, cross-ventilation of the roof space is required, and the handbook states that ventilation is vital for preventing excessive build-up of condensation in cold pitched roof spaces. Where a metal roof finish is used, a high performance vapour control layer is recommended near the inner surface with a ventilated air space on the cold side of the insulation. The numerical opening areas and the assessment method are not restated in the handbook: it directs the reader to BS 5250:2002 Code of practice for the control of condensation in buildings, naming Section 8 and Annex D for detailed assessment and construction methods, and to BRE Report BR 262 Thermal insulation: avoiding risks for acceptable insulation performance. Cite it alongside the roof ventilation figures when advising on boarding a loft or raising insulation depth.

  30. very strong RN-69H4L9

    Scottish Government (gov.scot)

    The in-force Scottish handbook, 13.6 MB PDF, applying from 6 April 2026. Figures a note on Scotland needs: Standard 4.6 requires a dwelling to have at least 4 thirteen-amp socket outlets in each apartment, 6 in the kitchen of which at least 3 above worktop level in addition to any for floor standing or built-in appliances, and a further 4 anywhere in the dwelling including at least 1 in each circulation area per storey, with no equivalent requirement in England. Clause 4.6.1 requires at least one lighting point in every circulation space, kitchen, bathroom, toilet and any space of 2 m2 or more; clause 4.6.2 sets 100 lux on stair flights and landings and 50 lux elsewhere in common circulation areas. Table 3.11 sets background ventilator equivalent areas of 12,000 mm2 per apartment and 10,000 mm2 for a kitchen, utility, toilet, bathroom or shower room, doubled where ducted, with part of the ventilator at least 1.75 m above floor level. Table 3.12 sets intermittent extract rates of 30 l/s over a hob, 60 l/s elsewhere in a kitchen, 30 l/s utility, 15 l/s bathroom or shower, 6 l/s WC, with fan and background ventilator at least 0.5 m apart. Table 6.2 sets maximum U-values of 0.17 wall, 0.15 floor, 0.12 roof, 1.4 windows, roof windows and doors, 2.1 rooflights, with a Window Energy Rating or Doorset Energy Rating of B or better as an alternative for units in an existing building; for 1 or 2 matching replacement windows the frame may be disregarded if the centre pane U-value is 1.2 W/m2K or less, secondary glazing should reach about 3.5 W/m2K, and total glazed area should not exceed 25 per cent of dwelling floor area. Clause 4.8.2 requires glazing to BS 6262-4:2018 within 800 mm of floor level, in a door leaf, or within 300 mm of a door leaf and within 1.5 m of floor level, with manifestation between 850 mm and 1.0 m and between 1.4 m and 1.6 m above floor level. Clause 4.8.3 requires any window or rooflight more than 4 m above adjacent ground or floor to be cleanable safely from inside per Clause 8 of BS 8213-1:2004, from a loadbearing surface, or from a mounted access system, sets safe reach limits of 610 mm downward and an 850 mm radius arc from a point not more than 1.3 m above floor level, and bars ladder access to glazing more than 9 m above the ladder's footing.

  31. very strong RN-8T0SVC

    Scottish Government (gov.scot)

    Scotland's equivalent of the Approved Documents, and the reason a note that quotes only English rules is wrong for a fifth of the UK. This edition is in force from 6 April 2026 and applies to building warrants submitted on or after that date and to work not requiring a warrant commenced from that date. It gives guidance on achieving the standards set in the Building (Scotland) Regulations 2004, arranged in sections rather than parts: section 3 environment (ventilation, drainage, condensation), section 4 safety (electrical safety and installations, glazing and danger from accidents, including clause 4.13 which invokes PAS 24 for security), section 6 energy (U-values for windows and doors) and section 7 sustainability. Scotland uses a building warrant and a completion certificate rather than a building notice, and has no Part P competent person scheme equivalent, so electrical work is covered by the warrant system instead.

  32. very strong RN-QT7ZA7

    Scottish Government (gov.scot)

    SCOTLAND, last updated 24 August 2026. Confirms the EPC in Scotland is administered separately from England and Wales: buildings are rated A to G with A most efficient, the certificate lists improvement measures with an indicative cost for each, and it is accompanied by a recommendations report. The assessment reflects the building not the occupants, using standard assumptions about occupancy and use, and carries no personal data other than the assessor's name and contact details. For non-domestic buildings the EPC shows an asset rating alongside primary energy use. The page states that EPCs in Scotland are being reformed by the Energy Performance of Buildings (Scotland) Regulations 2025, replacing the 2008 regulations, with new-style certificates and strengthened quality assurance. Enquiries go to EPCenquiries@gov.scot, not to an England service.

  33. very strong RN-M920CI

    The National Archives (legislation.gov.uk)

    Article 4(1) of the retained Construction Products Regulation requires a manufacturer to draw up a declaration of performance when a product covered by a designated standard, or conforming to a UK Technical Assessment, is placed on the market. Article 4(2) makes the declaration the only permitted route for stating performance against essential characteristics, so a performance claim outside the declaration is not valid. Article 4(3) provides that by drawing up the declaration the manufacturer assumes responsibility for the product's conformity with the declared performance, and that in the absence of objective indications to the contrary the declaration is presumed accurate and reliable. The words designated standard and UK Technical Assessment were substituted for harmonised standard and European Technical Assessment on 31 December 2020 by the Construction Products (Amendment etc) (EU Exit) Regulations 2019 (S.I. 2019/465), Schedule 1 paragraph 6.

  34. very strong RN-B7FKWF

    The National Archives (legislation.gov.uk)

    Sets out exactly what a declaration of performance must contain, which is what to look for when checking a product claim. Article 6(2) requires the product-type reference, the system or systems of assessment and verification of constancy of performance from Annex V, the reference number and date of issue of the designated standard or UK Technical Assessment used for each essential characteristic, and any Specific Technical Documentation reference. Article 6(3) requires the intended use or uses, the list of essential characteristics, the performance of at least one essential characteristic, performance stated by level, class or description, and crucially that any listed essential characteristic for which no performance is declared must carry the letters NPD, meaning No Performance Determined. Article 6(4) requires the declaration to follow the model in Annex III.

  35. very strong RN-BWO1CR

    The National Archives (legislation.gov.uk)

    The instrument that made the 2021 changes real, so a note can date them exactly. Regulation 1 sets citation and commencement on 15 June 2022, extending to England and Wales but applying to buildings and building work in England. Regulation 11 amends Schedule 1: it adds "to a reasonable standard" to entry L1(b)(i), inserts new requirement L2 on on-site generation of electricity (systems must be appropriately sized, have effective controls and be commissioned to produce the maximum electricity reasonable in the circumstances), and inserts a whole new PART O OVERHEATING with requirement O1, reproduced in full and carrying NO limits on application. Regulation 4 inserts regulation 4(4) and 4(5), a rule renovation guides almost never mention: where Part L imposes a requirement on the work, then on completion the whole building must comply with Part F or be no more unsatisfactory in relation to Part F than before the work began, so a Part L job such as new glazing or wall insulation drags a whole-house ventilation duty with it. Regulation 8 inserts regulations 40A and 40B, requiring the person carrying out the work to give the owner information about an on-site electricity generation system, and about the Part O overheating provision, no later than five days after completion. Regulation 17 is the transitional provision: the amendments do not apply where a building notice or initial notice was given, or full plans deposited, before 15 June 2022, provided the work started before 15 June 2023.

  36. very strong RN-OLMVVL

    The National Archives (legislation.gov.uk), Acts of the Scottish Parliament

    SCOTLAND. The default rules for organising and paying for common repairs in a Scottish tenement, in force since 28 November 2004. Rule 1.2 defines scheme property and rule 1.4 a scheme decision; maintenance expressly includes repairs, replacement, the installation of insulation, cleaning, painting, routine works and gardening, but not demolition, alteration or improvement unless reasonably incidental. Rule 2.2 allocates one vote per flat and rule 2.5 makes a scheme decision by simple majority of all votes allocated, so a single objecting owner cannot block a repair. Rule 2.6 requires at least 48 hours notice of a meeting, and rule 2.10 lets any owner who did not vote in favour and who would bear not less than 75 per cent of the costs annul the decision, within 21 days of a meeting they attended. Rule 4.1 lists the recoverable scheme costs including common insurance and door entry systems. Rule 4.2 shares maintenance costs equally among the flats unless the largest flat's floor area is more than one and a half times the smallest, in which case liability is apportioned by floor area; rule 4.3 applies that same floor-area test to the roof over the close.

  37. very strong RN-I5NTO7

    UK Health Security Agency

    UKHSA's cold weather health guidance, first published 2 November 2012 and last updated 28 April 2026, applying to England, reference GOV-15292. Establishes the alerting framework a heating or insulation note can anchor to: the UKHSA Cold-Health Alerting system is operated by the Met Office and runs from 1 November to 31 March each year, and this guidance forms the cold weather part of UKHSA's Adverse Weather and Health Plan, whose aim is to protect health and reduce harm from adverse cold weather. Issued in several formats including an HTML main version, an easy read PDF of 8 pages, a British Sign Language video, a two-page print version of top tips, and a poster, with easy-read translations added on 28 April 2026 in Arabic, Bengali, Gujarati, Hindi, Italian, Kutchi, Punjabi, Portuguese, Somali, Tamil and Urdu.

  38. very strong RN-Y8BXXY

    UK Health Security Agency and Centre for Climate and Health Security

    UKHSA guidance published 7 August 2025, applying to England, on the allergens and irritants in indoor air, useful for any note that claims a renovation improves or harms air quality. States that indoor bioaerosols can contribute up to 34 per cent of indoor air pollution, and that people in Western countries spend the majority of their time indoors. Identifies the protein-based allergens as mould spores, which thrive in damp poorly ventilated spaces such as bathrooms and arise from leaks, condensation, poor heating or inadequate ventilation; house dust mites, which thrive in warm humid environments in bedding, carpets and upholstered furniture; and pet dander from skin flakes, urine and saliva. Separately names non-protein respiratory irritants: volatile organic compounds emitted by paints, cleaning agents and air fresheners, and particulate matter from cooking, smoking and open solid-fuel fireplaces. Warns that energy efficiency and adaptation measures can have unintended consequences for indoor environmental quality, and that poorly installed mechanical ventilation can worsen air quality.

  39. very strong RN-MY15X0

    Welsh Government (gov.wales)

    The Welsh Approved Document L Volume 1, in force until 3 March 2027, and the source for Welsh window figures, which are not identical to England's. Table 10.1 sets, for new and replacement windows and roof windows, a maximum U-value of 1.4 W/(m2K) or WER Band B, with an alternative for replacements of 1.2 W/(m2K) centre pane or low-E secondary glazing, and a threshold U-value for retained windows of 3.3. Rooflights: 2.2 for new and replacement, threshold 3.8. Doors more than 60 per cent glazed: 1.4 or DSER Band C, alternative 1.2 centre pane, threshold 3.3. All other doors: 1.4 or DSER Band B, threshold 3.3. External fire doorsets as defined in Approved Document B Volume 1 may be 1.8. Transitional easements allowed timber windows at 1.6 or WER Band C and timber doors at 1.8 or DSER Band E only where a building notice, initial notice or full plans were given before 23 November 2023. Paragraph 11.35 requires an existing window or door worse than the column (c) threshold to be replaced to column (a); paragraph 11.37 states that windows and doors mean the whole unit including the frame, so replacing just the glazing or the door leaf while retaining the existing frame is not building work and does not have to meet the energy efficiency requirements, though upgrading as close as practicable is sensible; paragraph 11.38 caps the total area of windows and doors at 25 per cent of total floor area where one is enlarged or created.

  40. very strong RN-JOH3I6

    Welsh Government (gov.wales)

    The Welsh Government landing page that shows which edition of Approved Document L applies in Wales and when. Two editions of Volume 1 (dwellings) sit side by side: the current edition in force until 3 March 2027 at /sites/default/files/publications/2024-05/building-regulations-approved-document-l-vol-1.pdf, and the 2026 edition in force from 4 March 2027 at /sites/default/files/publications/2026-04/building-regulations-approved-document-l-vol-1-2026.pdf. Note the date differs from England, where the 2026 edition of Approved Document L takes effect on 24 March 2027, so a note giving a single UK-wide changeover date is wrong for Wales by three weeks.