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Window lintels and who should deal with them
A lintel is the support over a window opening, and changing that support is building work, not a glazing swap. In Cheshire, ask building control and a builder before anyone widens the hole, and do not treat a 2013 council leaflet as a local price list.
Last reviewed:The beam over the opening
People use "lintel" for the beam over a window or a door. Ask the builder to write the steel, the bearing and any propping. Those are questions for the person who will answer to building control.
The GOV.UK booklet on building work, replacements and repairs was updated on 3 November 2014 and applies to England [S1]. Replacement of window and door units is one example of work you need to tell a building control body about, unless an installer registered with a relevant competent person scheme self-certifies it [S1]. The booklet says its lists are not complete [S1]. If you are in doubt, contact a building control body before work starts [S1]. A scheme installer should arrange the notification and you should receive a certificate of compliance within 30 days of completion [S1]. FENSA is one of the names the booklet lists for replacement windows and doors [S1].
GOV.UK: building regulations approval. QuoteZila is not affiliated with this organisation.
What a 2013 council note says about support
Lancaster City Council's building control guidance note on replacement windows and doors to dwellings was issued on 21 January 2013 [S2]. It is a Lancashire council leaflet, not a Cheshire East or Cheshire West and Chester decision. Two structural sentences in it are worth quoting in plain words.
First, a competent-person installer does not remove the need for a building regulations application where there are structural alterations to accommodate the windows, and the example given is an existing opening made wider so that a new support lintel is installed [S2]. Second, if the replacement windows are wider than those they replace, or the job involves bay windows, the surveyor needs to be satisfied that proper structural support is provided above the window and that bay corner posts are adequate [S2]. The note says that in many older buildings the timber frame carried the load of a wall or roof without a lintel, and that in those cases either a lintel is installed or the new frame is reinforced to carry the load [S2].
That leaflet also prints thermal numbers from 2013. Leave those numbers off the quote. Current heat-loss limits are a different document. The Planning Portal says the U-value of replacement windows and doors should not be exceeded and points readers to Approved Document L for the maximum allowed [S3]. Ask the installer for the figure they are working to, in writing, rather than copying an old leaflet.
Planning is a second door
Building regulations and planning permission are different. The GOV.UK booklet says the first is about how a building is constructed, and the second is about whether the development should go ahead [S1]. The Planning Portal says repairs, and new windows of a similar appearance, do not usually need planning permission [S6]. An upper-floor side window must be obscure-glazed and either non-opening or more than 1.7 metres above the floor [S6]. A new bay is treated as an extension and may need permission [S6]. Listed buildings, conservation areas, an Article 4 direction and a lease can change that, so ask the planning authority [S6].
Since 1 April 2002, the Planning Portal says, building regulations have applied to all replacement glazing, including thermal performance, safety, air supply, means of escape and ventilation [S3]. An external window or door is a controlled fitting [S3]. You can use a competent-person installer, who certifies the work, or you can ask a building control body to check it [S3].
Cheshire walls are not the Lancaster leaflet
QuoteZila's first towns are Crewe, Nantwich and Sandbach, and anyone in the UK can still post a job or register a business [QZ5]. A Lancashire leaflet has not seen your wall, so the quote has to describe it.
What to put in the request
Send each business the same note: wall material, approximate width and height measured from the floor, whether you want the opening wider or the same size, bay or flat, and photos taken from ground level. Say if the window is already out. Do not climb for a closer picture.
Citizens Advice says to get the quote in writing, because after you accept, the agreement binds you even if it was never written down [S4]. A quote should include a fixed total, a breakdown, how long the price stays open, and whether VAT is included [S4]. The VAT line matters because taxable turnover over £90,000 in the last 12 months means the business must register [S5]. Some traders charge to prepare a quote, so ask before they visit [S4]. If you cannot avoid a deposit, do not agree more than 25%, and take a receipt [S4].
| Line on the quote | Why you asked | If the line is blank |
|---|---|---|
| Opening size now, and size proposed | Wider can mean a new support [S2] | Do not let work start |
| Existing lintel stays, or a new one is supplied | The 2013 note separates those cases [S2] | Ask which case this is |
| Who contacts building control | Scheme installer or you [S1] [S3] | Get a name and a date |
| Certificate expected within 30 days if a scheme installer does a replacement unit [S1] | You may be asked for it when you sell [S1] | Chase the scheme, not a neighbour |
| Structural calculations, if the opening changes | A doubt for building control [S1] | Pause |
| VAT included or not, against the £90,000 line [S5] | So the totals compare | Ask for one figure |
Who you are hiring
Honest status: QuoteZila is new. We're starting in Cheshire, beginning with Crewe, Nantwich and Sandbach, and growing area by area. Anyone in the UK can still post a job or register a business. How fast you get quotes depends on how many local businesses have joined near you. Businesses can register and receive jobs straight away. We don't check insurance, qualifications or registrations, so please check these yourself before you hire.
Citizens Advice says to ask to see insurance and to check it lasts until the work finishes [S4]. Public liability is the cover it describes for injury or property damage [S4].
Up to five matched local businesses can reply [QZ2]. QuoteZila is free for customers and local businesses [QZ1].
Posting a job is not open yet
The trade pages that sit next to this question are builders, glaziers and joiners. Reading a written price on a different job is covered in driveway cost and fencing cost.
This page is general information, not professional or legal advice. QuoteZila does not check Gas Safe, WaterSafe, NFRC, NICEIC or other registrations against the register on your behalf: look them up yourself.
Jobs you might post
These are examples, not taken from real job posts.
- "Single window in a brick terrace in Crewe. Same opening size. I want to know if a lintel is already there before the frame comes out."
- "Bay on a house in Nantwich. Corner posts and the beam over the bay. No widening unless you explain it in writing."
- "Kitchen window in Sandbach to be wider by a small amount. Please include building control in the quote and do not start on a verbal yes."
Questions about lintels
Can I cut a new window opening myself?
No. Cutting masonry and propping a wall are for the person who will answer to building control. GOV.UK's booklet on home building work says the lists of jobs are not complete, and that if you are in any doubt you should contact a building control body before starting. Widening an opening so that a new support is required is the sort of doubt that booklet points to a building control body, and a 2013 Lancaster note says a competent-person window installer does not remove that application where the opening is made wider for a new support lintel.
Does a like-for-like window still involve the lintel?
Replacing the window unit is itself an example of work to tell a building control body about, unless a competent-person installer certifies it. The Planning Portal says building regulations have applied to all replacement glazing since 1 April 2002, and that an external window is a controlled fitting. Lancaster's 2013 note adds a structural point: if the new windows are wider, or the job is a bay, the surveyor needs to be satisfied about support above the window and about bay corner posts. A same-size swap can still be a controlled fitting even when the lintel stays.
What should the builder's quote name?
Ask for the opening width, whether the existing support stays, and who tells building control. Citizens Advice says a quote is a promise to do the work at an agreed price, and that you should not rely on a verbal quote. Try to collect written quotes from at least three traders, and ask whether VAT is in the total. Registration for VAT is required when taxable turnover for the last 12 months goes over £90,000.
Is a new bay just a window?
The Planning Portal says a new bay window will be treated as an extension and may require permission. That is a planning question, separate from building regulations. Lancaster's note says a bay replacement means the surveyor looks at corner posts as well as the support above the window. Ask your own council. A Lancashire leaflet is not a decision for a house in Cheshire.
Does QuoteZila check the businesses?
No. We don't check insurance, qualifications or registrations, so please check these yourself before you hire. You can report a quote or a business from your job page.
Related trades
Cost guides
Related pages
- Brick Spalling: What the Face of the Wall Shows. Brick spalling is the outer face of a brick breaking away. In Cheshire, ask whether the wall still resists weather, and check listing before major work.
- Bricking Up a Doorway or Window: What to Check. What bricking up a door, window or fireplace opening involves, when building regulations or planning may apply, and what a builder's quote should cover.
Sources
- QZ1: QuoteZila product fact. QuoteZila public pricing line.
- QZ2: QuoteZila product fact. QuoteZila terms, customers.
- QZ5: QuoteZila product fact. QuoteZila coverage wording.
- S1: Building work, replacements and repairs to your home, GOV.UK. Accessed 2026-10-25. https://www.gov.uk/government/publications/building-work-replacements-and-repairs-to-your-home/building-work-replacements-and-repairs-to-your-home
- S2: Building Control Guidance Note 05, replacement windows and doors to dwellings, Lancaster City Council. Accessed 2026-10-25. https://www.lancaster.gov.uk/assets/attach/1344/Leaflet-5-Replacement-Windows-to-Dwellings.pdf
- S3: Building regulations: doors and windows, Planning Portal. Accessed 2026-10-25. https://www.planningportal.co.uk/permission/common-projects/doors-and-windows/building-regulations
- S4: Before you get work done on your home, Citizens Advice. Accessed 2026-10-25. https://www.citizensadvice.org.uk/consumer/getting-home-improvements-done/before-you-get-building-work-done/
- S5: Register for VAT, GOV.UK. Accessed 2026-10-25. https://www.gov.uk/register-for-vat
- S6: Planning permission: doors and windows, Planning Portal. Accessed 2026-10-25. https://www.planningportal.co.uk/permission/common-projects/doors-and-windows/planning-permission