Grey uPVC windows, particularly Anthracite Grey (RAL 7016), have become one of the most popular alternatives to white in UK homes. They carry a price premium over standard white uPVC, but the difference has narrowed as grey windows moved from specialist to mainstream production. In 2026, a grey uPVC casement window typically costs £340–£950 fully installed, depending on size, glazing specification, and glazing company, and about £450–£800 for a standard 900 x 1050 mm casement.

Why Grey uPVC Costs More Than White

White uPVC windows are extruded, cut, and welded in high volumes from a single standard compound. Coloured uPVC requires one of two techniques:

  1. Film lamination (foiling), a coloured PVC film is bonded to a white uPVC profile after extrusion. This is widely used for grey uPVC, and foiling only the outer face gives two-tone windows (grey outside, white inside). REHAU, for example, supplies its colour range, including Anthracite Grey, as foil laminates bonded to the profile.1

  2. Co-extrusion or colour-through profiles, coloured compound forms the outer layer of the extrusion itself. Fewer systems offer this, usually in a small number of popular shades.

The additional material (colour compound or film) and the extra production step add to the frame cost over white uPVC. Labour and glazing costs are unchanged, so across the table below the installed premium for Anthracite Grey works out at roughly 20–25%.

Grey uPVC Window Prices: 2026 Breakdown

Every price below is for one window, supplied and installed:

Window typeWhite uPVC installedAnthracite Grey installed
Small casement (500 x 900 mm)£280–£450£340–£560
Standard casement (900 x 1050 mm)£380–£650£450–£800
Large casement (1200 x 1050 mm)£480–£750£580–£950
Standard top-hung (900 x 500 mm)£280–£450£340–£560
Bay window (3-light, standard)£1,400–£2,200£1,700–£2,800
Tilt-and-turn (900 x 1050 mm)£500–£850£600–£1,050
Sash window uPVC (750 x 1200 mm)£550–£900£650–£1,100

All prices above are for double glazing with a low-E coating. Triple glazing adds approximately 15–25% to the above. Prices are supply and fit including VAT at the standard rate of 20%.2

Colour nameRAL codeNotes
Anthracite GreyRAL 7016By far the most popular; near-black grey
Agate GreyRAL 7038Lighter, warmer mid-grey
Window GreyRAL 7040Traditional lighter grey, like aluminium
Mouse GreyRAL 7005Medium neutral grey
Steel BlueRAL 5011Very dark blue; a softer alternative to near-black grey

Anthracite Grey is the usual grey choice for new-build and replacement windows alike. It pairs well with red brick, lime render, and white render, the three most common UK house exteriors. Agate Grey is increasingly chosen for properties where a slightly softer tone is preferred.

Full House Replacement Window Costs

For a typical UK semi-detached house with 8–12 windows:

House typeWindowsWhite uPVC (supply and fit)Anthracite Grey (supply and fit)
2-bed terrace6–8 windows£2,800–£5,000£3,400–£6,200
3-bed semi9–12 windows£4,200–£7,500£5,100–£9,500
4-bed detached12–16 windows£5,500–£9,500£6,800–£12,000

These are broad ranges, glazing companies vary significantly in pricing, and quotes for the same full-house job from a local installer and a large national glazing company can differ by thousands of pounds. National companies often charge more; local FENSA- or CERTASS-registered installers with good reviews often represent better value.

Two-Tone Windows

A significant proportion of UK homeowners choose grey outside, white inside, matching the exterior aesthetic while keeping interior sills and reveals bright. This is usually achieved with film lamination on the outer face only.

Two-tone windows typically add £30–£80 per window over single-colour grey, less than the difference between white and grey.

Building Regulations and FENSA

Replacing windows in England is notifiable building work, and the replacement has to satisfy Part L (conservation of fuel and power), Part F (ventilation) and Part K (safety glazing) alike. You can use an installer registered with a competent person scheme, FENSA or CERTASS, both of which are authorised to self-certify replacement windows and doors in existing dwellings, who will issue you a completion certificate.3 This is essential for:

  • Satisfying solicitors when you sell the property
  • Showing that the work met the Building Regulations if a buyer, lender or insurer asks

Key performance requirements (2026):

  • Whole window U-value: 1.4 W/m²K or Window Energy Rating Band B, the limit for a new or replacement window in an existing dwelling (Part L, England)4
  • Safety glazing: toughened or laminated in critical locations, to Class 3 of BS EN 12600 or Class C of BS 6206 (Part K in England,5 Part N in Wales6)
  • Trickle vents: if the old windows had background ventilators the new ones must match or better them, and if they had none the ventilation must still be no worse than before, normally 8,000 mm² equivalent area in each habitable room and the kitchen and 4,000 mm² in a bathroom (Part F)7

Grey uPVC windows meet all of these requirements from standard double-glazed production, the colour does not affect thermal performance.

Planning Permission for Grey Windows

For a house in England, replacing windows is usually permitted development as long as the new windows are of a similar appearance to the existing ones.8 A switch from white to grey can be argued either way, so if your house is in a sensitive location it is worth asking your local planning authority first. Exceptions:

  • Listed buildings, any external appearance change requires listed building consent. uPVC replacements are rarely accepted on listed buildings; like-for-like timber or metal windows matching the original are normally expected.
  • Conservation areas, some conservation area Article 4 Directions withdraw permitted development rights for window changes. Check with your LPA before ordering.
  • New-build with restrictive covenants, some developers’ covenants specify window colours; check your title documents.
  • Flats, householder permitted development rights do not apply to a flat or to a building containing flats, so a colour change may need planning permission.9 Leaseholders may also need the landlord’s consent.8

How to Get the Best Price

  1. Get at least three quotes, window pricing is highly variable between companies.
  2. Avoid signing at the first appointment, high-pressure sales tactics are common in the glazing industry; take the quote away and compare.
  3. Check the energy rating, a replacement window must reach at least band B (or a U-value of 1.4 W/m²K), and A-rated or better windows lose less heat. Ask for the rating label with the quote.
  4. Ask about the fabricator, the profile manufacturer (Rehau, Spectus, Deceuninck, Veka) is a reasonable indicator of quality; all major brands produce good Anthracite Grey ranges.
  5. Check the FENSA or CERTASS registration, verify on the scheme’s own website before signing.
References (9)

Figures in this note were checked against the sources below on 30 September 2026. Superscript numbers in the text point to them. Every source the site cites, by topic.

  1. 1technicalsupplier figureREHAU, guidance.RN-IU7D7UREHAU's window profile colour brochure. It shows its colours, including Anthracite Grey (similar to RAL 7016), supplied as PVC foil laminates bonded to the uPVC profile.
  2. 2technicalvery strongHM Revenue & Customs (GOV.UK), guidance.RN-4W7T33Sets the three UK VAT rates: standard 20% on most goods and services, reduced 5% on some goods and services such as children's car seats and home energy, and zero 0% on zero-rated goods such as most food and children's clothes. The standard rate rose to 20% on 4 January 2011 from 17.5%. Some supplies are exempt rather than rated, including postage stamps and financial and property transactions. This is the reference for converting a merchant's ex-VAT trade quote into the figure a homeowner actually pays.
  3. 3technicalvery strongMinistry of Housing, Communities and Local Government.RN-SAMO3MThe official list of competent person schemes whose members can self-certify certain building work instead of getting building regulations approval, published 4 April 2013 and last updated 12 March 2018. Named schemes with contact numbers include ATTMA, APHC, Assure Certification, Blue Flame Certification, the British Board of Agrement, BESCA, Capita Gas Registration and Ancillary Services trading as Gas Safe Register, CIGA, Certass, Certsure LLP trading as NICEIC, the Elmhurst Airtightness Scheme, Fensa Limited, HETAS Limited, NAPIT Registration Limited, the National Federation of Roofing Contractors trading as CompetentRoofer, and OFTEC. Two footnotes matter: the Gas Safe Register is not technically a competent person scheme although in practice its installers carry the same building regulations responsibilities, and Benchmark Certification Limited ceased to operate as a competent person scheme on 10 February 2017, becoming part of NAPIT Registration Limited that day. Installers joining an electrical scheme are added to the single electrical competent person register.
  4. 4technicalvery strongMinistry of Housing, Communities and Local Government.RN-L0FCJXThe in-force U-value tables a DIY insulation or door note must quote, with the exact numbers. Table 4.2, limiting U-values for new fabric elements in existing dwellings, sets roof 0.15, wall 0.18, floor 0.18, swimming pool basin 0.25, window 1.4 or Window Energy Rating Band B minimum, rooflight 2.2, doors with more than 60 per cent of the internal face glazed 1.4 or Doorset Energy Rating Band C minimum, and other doors 1.4 or Doorset Energy Rating Band B minimum. Table 4.3, for existing elements, gives a roof threshold of 0.35 and an improved value of 0.16, which is the figure a loft insulation note needs: paragraph 4.12 says a retained element whose U-value is higher than the column (a) threshold, for example through a loft or garage conversion, should be upgraded to the column (b) value. Paragraph 4.13 allows a lesser upgrade only where the improved value is not technically or functionally feasible or would not achieve a simple payback of 15 years or less. Paragraph 4.8 requires a replacement element to be no worse than the one it replaces as well as meeting Table 4.2. Paragraph 4.10 gives the heritage exception: where character must be maintained, a centre pane U-value of no more than 1.2 or low-emissivity secondary glazing. Note 9 records that the timber window concession of 1.6 or Band C ended on 14 June 2023. The 2021 edition came into force on 15 June 2022; a 2026 edition exists at https://assets.publishing.service.gov.uk/media/69c122a6cfa346b9d4704a55/ADL1_2026.pdf.
  5. 5technicalvery strongMinistry of Housing, Communities and Local Government.RN-XH6E39The standard that decides whether a loft ladder is legal and when a raised deck needs a balustrade. Published 3 January 2013, it covers protection from falling, collision and impact including stairs, ladders, ramps, guarding and vehicle barriers. Paragraph 1.31 states that retractable ladders must not be used as a means of escape. Paragraph 1.32 permits a fixed ladder, with fixed handrails on both sides, only for access in a loft conversion containing one habitable room, and only where there is not enough space without altering the existing space for a compliant stair, which is the rule that catches most loft ladder installations. Paragraph 1.29 restricts alternating tread stairs to loft conversions. For a private stair the maximum pitch is 42 degrees (Table 1.1 note 1), the normal relationship between rise and going is twice the rise plus the going between 550mm and 700mm, and for dwellings external tapered steps forming part of the building need a going of at least 280mm. Paragraph 3.1 requires guarding wherever it is reasonably necessary for safety at the edge of a floor, gallery, balcony, roof, light well, basement or similar sunken area. Paragraph 3.2 requires guarding to be at least the height in Diagram 3.1, allows any wall, parapet or balustrade to serve as guarding, and requires it to resist the loads in BS EN 1991-1-1 with its UK National Annex and PD 6688-1-1, with BS 6180 for barrier and infill panel design. Handrails should be positioned 900mm to 1000mm from the pitch line or floor.
  6. 6technicalvery strongWelsh Government.RN-58G48FWales retains Part N, which England revoked in 2013 and folded into Part K, so a note that says 'Part K in England, Part N in Wales' for safety glazing is correct. Current Welsh guidance incorporating September 2013 amendments, published 5 April 2017. Covers glazing in critical locations (below 800 mm from floor level in a window, below 1500 mm in a door or a side panel within 300 mm of a door), safe breakage, manifestation of large glazed areas, and safe opening, closing and cleaning of windows. PDF at gov.wales/sites/default/files/publications/2019-05/building-regulations-guidance-part-n-glazing-safety.pdf. Also states that a replacement window opening should give at least the same potential for escape as the one it replaces.
  7. 7technicalvery strongMinistry of Housing, Communities and Local Government.RN-QD1SFFTable 1.1 sets minimum intermittent extract rates: kitchen with a cooker hood extracting outside 30 l/s, kitchen without one 60 l/s, utility room 30 l/s, bathroom 15 l/s, sanitary accommodation 6 l/s. Extract terminals and fans other than cooker hoods should be as high as practicable and no more than 400mm below the ceiling; a cooker hood should sit between 650mm and 750mm above the hob if the manufacturer gives no figure. Table 1.7 requires background ventilators of at least 8000mm2 equivalent area in habitable rooms and kitchens for a dwelling, 10,000mm2 for a single-storey dwelling. Background ventilators should be at least 1700mm above floor level and at least 500mm from a fan in the same room. On replacement windows, paragraph 3.14 says new windows must carry background ventilators no smaller than the originals, and paragraph 3.15 gives the fallback minimums where the old size is unknown: 8000mm2 habitable rooms, 8000mm2 kitchen, 4000mm2 bathroom. Paragraph 3.32 confirms that replacing an extractor fan or cooker hood on existing cabling is not notifiable.
  8. 8technicalvery strongPlanning Portal, guidance.RN-LIPHMWThe Planning Portal on planning permission for doors and windows: usually not needed for repairs, maintenance and minor improvements including replacing windows like for like, with the exceptions that catch people, listed buildings, conservation areas, flats, and where permitted development rights have been removed.
  9. 9technicalvery strongThe National Archives, guidance.RN-EZ53YYArticle 2 of the GPDO defines dwellinghouse for Part 1; the definition excludes buildings containing flats and the flats within them.

  1. Complete foil colour range: decorative designs for REHAU window and door profiles, REHAU, accessed 30 September 2026. rehau.com

  2. VAT rates, HM Revenue and Customs (GOV.UK), accessed 10 September 2026. gov.uk

  3. Competent person scheme: current schemes and how schemes are authorised, Ministry of Housing, Communities and Local Government (GOV.UK), accessed 10 September 2026. gov.uk

  4. Approved Document L, Conservation of fuel and power, Volume 1: Dwellings, 2021 edition incorporating 2023 amendments, Ministry of Housing, Communities and Local Government, accessed 10 September 2026. assets.publishing.service.gov.uk

  5. Approved Document K, Protection from falling, collision and impact, 2013 edition, Ministry of Housing, Communities and Local Government, accessed 10 September 2026. assets.publishing.service.gov.uk

  6. Approved Document N: glazing (safety in relation to impact, opening and cleaning), Welsh Government, accessed 10 September 2026. gov.wales

  7. Approved Document F, Ventilation, Volume 1: Dwellings, 2021 edition, Ministry of Housing, Communities and Local Government, accessed 10 September 2026. assets.publishing.service.gov.uk

  8. Doors and windows: planning permission, Planning Portal, accessed 30 September 2026. planningportal.co.uk

  9. The Town and Country Planning (General Permitted Development) (England) Order 2015, article 2: interpretation, legislation.gov.uk, accessed 30 September 2026. legislation.gov.uk