Window film surveys in London
Get the right film for your windows, first time.
From £150, depending on how many windows
In short
Fitting the wrong window film to the wrong glass can cause cracking, failed double-glazing seals and voided warranties. Simply Filtered's pre-installation window film survey measures each window before any film is chosen: glass thickness, whether the glass is toughened, laminated glass where identifiable, cavity gaps in double glazing and any existing Low-E (heat-reflecting) coating. Duncan Ridley, who has completed 3M window film training, writes up the findings for each window so a film supplier can recommend a film that suits the glass. The survey covers London inside the M25.
Sound familiar?
You want film, but you don't know what glass you've got.
- “Every installer tells me something different.”
- “I don't know if my glass is toughened.”
- “I've read that film can crack double glazing.”
- “Will it void the warranty on my windows?”
Windows in the same house often differ, so what suits your back door may be wrong for your bay window. Measuring each one first means the film you choose suits the glass it's going on.
Why the glass matters: does window film damage double glazing?What I measure
Five things your film supplier needs to know about every window.
Each one changes which films are safe and suitable for that pane, so each is measured, window by window.
- Glass thickness
- How thick each pane is.
- Thickness affects how a pane copes with the heat a film can add, so your supplier needs it to choose a suitable film.
- Toughened or not toughened
- Toughened glass is heat-treated to be stronger, so it breaks into small blunt pieces. Each of your panes is tested with a Merlin Lazer toughened glass indicator.
- Ordinary glass is more sensitive to heat stress than toughened glass, which narrows the films that suit it.
- Laminated glass
- Two panes bonded with a clear plastic layer, so the glass holds together if it breaks. Recorded where it can be identified.
- It looks like ordinary glass from most angles, so it's worth knowing rather than assuming before a film is chosen.
- Cavity gap
- The space between the two panes of a double-glazed unit.
- Your supplier uses it, with the glass details, to judge how a film will affect the sealed unit.
- Low-E coating
- A thin, invisible coating that reflects heat back into the room.
- You can't see whether your glass has one, and it changes which films are suitable, so it's checked on every pane.
Image: A window film survey report listing measurements for each window
What you get
A written report of the measured findings for each window.
Your report records the glass and cavity details for every window you asked about, so a film supplier can recommend a film that suits each one. It's based on measurements, not assumptions.
Final film selection and warranty stay with your film supplier or installer.
The wrong film on the wrong glass can cost you more than no film at all.
Two ways to use your report
Your report, your choice of supplier.
Option one
Take it to your own supplier
Give your report to any film supplier or installer you like. They get the glass details they need without an extra visit to measure.
Option two
Pass it to my local suppliers
Ask me to pass your report to my established local film suppliers, who can advise on the right film and give you a quotation.
Prices
What a window film survey costs.
A base fee of around £100 covers travel, setup and your written report, plus roughly £12 to £15 per window, or per sealed unit where a window has several panes.
| Property | Approx. windows | Price |
|---|---|---|
| Small flat | 4 to 6 | From £150 |
| Typical 2 to 3 bed house | 8 to 12 | From £200 |
| Larger house | 15 to 20 | From £300 |
| Commercial, or more than 20 windows | 20+ | Quote on the day |
- A travel supplement may apply outside central and west London.
- Say roughly how many windows you want measured and you get an exact price.
How it works
From your enquiry to choosing your film.
Send the form
Tell me roughly how many windows you'd like measured. The enquiry takes about 2 minutes.
Get your free quote
You get a reply with your exact price. If you're happy to go ahead, we agree a time that suits you.
The survey
Every window you asked about is measured, pane by pane, while you get on with your day.
Your report, then your supplier
You get the written findings for each window. Take them to any supplier, or ask me to pass them on. No obligation either way.
Who it's for
For homeowners and landlords, and for the trade.
Homeowners and landlords
Measured advice before you buy film.
Know exactly what glass you have before anyone recommends a film, so you're not relying on guesswork or a sales pitch.
- Every window you ask about, measured one by one
- A written report you keep
- Your own supplier, or my local suppliers: your choice
Film suppliers and installers
Reliable glass data without the extra site visit.
Get measured glass details in hand before you quote, instead of travelling out to identify the glass yourself.
- Thickness, toughened or not, laminated where identifiable, cavity gap and Low-E, per window
- Measured on site with dedicated diagnostic equipment
- Glass and cavity details only: specification and warranty stay yours
Questions
Questions about window film surveys.
How do I know if my glass is toughened?
Toughened glass often has a small etched mark in one corner, but not always, and laminated glass and Low-E coatings usually can't be spotted by eye. On a survey, each of your panes is tested with a Merlin Lazer toughened glass indicator and recorded as toughened or not toughened.
Can window film crack double glazing?
It can when the film doesn't suit the glass. Fitting the wrong film to the wrong glass can cause cracking, failed double-glazing seals and voided warranties. Measuring the glass first lets your supplier choose a film that suits it.
Can't the installer just tell me what glass I have?
A good installer will ask, and may check. A measured report means you know before you choose, window by window, and you can compare quotes from different suppliers against the same information.
How much does a window film survey cost?
Prices start from £150 for a small flat, and depend on how many windows you want measured. A base fee of around £100 covers travel, setup and your written report, plus roughly £12 to £15 per window, or per sealed unit where a window has several panes. Say roughly how many windows you want measured and you get an exact price.
Do you supply or fit the film?
Not at the moment. The survey is a diagnostic assessment and does not include installation or film supply. You can take your report to any supplier, or ask me to pass it to my local film suppliers for advice and a quotation.
Does the survey certify my glass as safety glass?
No. Toughened glass is reported as toughened or not toughened. The survey does not certify glass as safety glass or as meeting any British Standard.
Next step
Get the right film for your windows, first time.
Tell me roughly how many windows you want measured and you get an exact price back. You are under no obligation to use anyone I recommend.
WhatsApp meOr call 07366 199261