Receiving several quotes for new windows or doors is a normal part of the buying process. However, many homeowners are surprised to see that prices for seemingly similar solutions can differ by 20–30% or even more. In most cases, these differences result from variations in product specification, installation scope, finishing works and warranty conditions.
The answer to the question “How do I compare window and door quotes?” is: don’t focus only on the price. Take a closer look at what the company actually puts in the offer. First, check things like glazing quality, thermal values, hardware standard, locking systems.
In this Fenbro guide, we explain how to analyse window and door quotations step by step. You will learn what to check and how to spot hidden differences.
Step 1: Make sure you are comparing like-for-like quotes
Looking only at the total price can lead to totally wrong conclusions. A lower quote doesn’t always mean better value, and a higher price doesn’t always guarantee better performance. The cheapest offers… can become the most expensive over time. Surprised?
Before analysing the final price of any window or door quote, it is worth taking a step back and looking at the bigger picture. At first glance, several offers from various companies may appear similar – they may even include products of a comparable style or size. However, once you look more closely, you may notice that the scope, technical details or level of service differ significantly.
Make sure you are comparing:
- the same number of units
- the same dimensions
- the same colour or veneer finish
- the same glazing specification
- the same hardware or security standard
- the same clearly defined installation scope (if fitting is included)
Quick tip:
If at least three of these details are not specified, it is better not to compare the bottom-line price yet. First, ask the company for clarification, otherwise the comparison may simply not be fair.
Step 2: What must be included in a good window quote?
Once you know that the quotes you received are based on similar sizes and general configurations, the next step is to look at the details. This is usually the moment when customers realise that offers which seemed almost identical at first can, in fact, differ quite significantly in terms of quality and long-term performance.
A reliable window quote should clearly show what product you are being offered. Not just a general description like “uPVC windows” or “aluminium frames”, but specific technical information that helps you understand how the window will perform.
Construction and system
The quotation should always include the system or profile name, as well as basic structural characteristics such as the installation depth, number of chambers and type of reinforcements used inside the frame. It is also worth checking the hardware specification. Additional functions such as micro-ventilation or trickle vents may also be listed here, depending on the configuration.
Glazing and thermal performance
Another important part of the specification is the glazing unit. It’s worth checking if the quote clearly says whether the window is double or triple glazed and what the Ug value of the glass is. You can also look for information about a warm edge spacer. If additional safety is important, the specification may mention toughened (ESG) or laminated (VSG) glass. Most importantly, the offer should show the Uw value, as this reflects how the whole window performs in real life.
As Hubert, our Quoting Team Leader, explains:
‘’In cheaper quotes, companies most often use standard glazing for doors, sliding systems and large fixed windows. In our case, these are always toughened glass units, where the risk of breakage is practically minimal. And with standard glass used in front doors or sliding doors, the risk of cracking or damage is much higher.’’
Feeling a bit lost with all the factors like Uw or Ug? Please check this article: Joinery glossary explained – everything you need to know about window and door parameters
Acoustic comfort and security features
Sometimes the offer may also mention acoustic performance, for example an Rw value, significantly if reducing outside noise is important. You might also see information about security – number of locking points, handle type or resistance classes like RC2. Checking these points helps you understand what level of comfort and protection you can expect once the windows are fitted.
Step 3: What should be included in a door quote?
Got quotes just for doors, or maybe for windows and doors together? Either way, it is worth checking what has actually been included.
Start with the Ud value, which shows how the entire door performs thermally. Then look at the locking system – not only how many locking points there are, but also what type of cylinder or security hardware is specified. These details affect how safe and tight the door will feel in daily use.
It is also sensible to check practical elements such as hinges, opening direction, threshold type and glazing features, especially if the design includes sidelights or glazed panels. Some quotes may also mention acoustic performance or resistance class, which can be important depending on location and security needs.
If the offer includes patio doors, the system name should always be clearly stated. Lift-and-slide, tilt-and-slide or newer smart-slide solutions differ from each other. Read more in these articles: What is the difference between HST and PSK sliding doors? and Modern smart-slide doors – an alternative to traditional door solutions.
Please note: sliding doors are often specified in a similar way to windows. A clear quotation should still show the system, glazing configuration, hardware details and thermal performance values. Understanding these basics makes it much easier to compare offers and see where price differences come from.
Step 4: Installation scope and finishing works
It is completely natural to focus mainly on the products when reviewing quotes. This is what most customers do first. Because of that, one important element can sometimes be overlooked… and that is the installation!
In reality, the total price can vary quite a lot depending on what is included in the fitting service. Some quotes cover measurement, removal of old windows or doors, delivery and waste disposal, while others list these as additional costs. It is also worth checking how the products will be fitted and sealed into the wall opening. The installation method and finishing standard can influence comfort and long-term performance. Details such as window boards, trims or internal finishing works should also be clearly described. If they are not included from the start, they may increase the final cost later.
In some companies (including Fenbro), installation is organised under a separate agreement with an independent fitting team. This is quite common when one company supplies the windows or doors and another carries out the fitting. What matters is knowing who is responsible for what. The installation quote, all arrangements and any potential complaints related to the fitting are agreed directly with the installers, without Fenbro acting as a middle party.
Step 5: Payments, timing and warranty
When you already know what product you are getting and how the installation will look, it is worth checking a few more things.
Start with payments. Every company works a bit differently. Sometimes you pay a higher deposit, sometimes the cost is divided into stages. It is simply good to know this from the beginning.
Then look at timing. Windows and doors are not usually taken from stock. They can be custom-made for your project, so production and delivery can take time. A clear lead time helps you plan the rest of the work.
It is also reasonable to ask about warranty. What is covered, for how long, and who you contact if something goes wrong or needs adjusting later.
These points are not the first things customers focus on. But once the project starts, they can quickly become very important.
Example – window quote comparison
Below you’ll find a comparison table showing how seemingly similar quotes can vary. There is a saying: the devil is in the details. Can you spot all the differences?
| Specification element | Offer A | Offer B | Offer C |
|---|---|---|---|
| Brand | Salamander | Veka Softline | Not specified |
| Material | uPVC multi-chamber system (e.g. 82 mm depth) | uPVC 5-chamber system | Basic uPVC profile |
| Size | 1000 x 1000 | 1000 x 1000 | 1000 x 1000 |
| Opening type | Tilt & turn | Tilt & turn | Tilt & turn |
| Ug value | 0.5 W/m²K | 0.7 W/m²K | Not specified |
| Uw value | 0.80 W/m²K | 1.0 W/m²K | 1.3 W/m²K |
| Glazing unit | Triple glazing with warm edge spacer | Triple glazing | Double glazing |
| Glass specification | Low-E coating + argon filled | Low-E coating | Standard glazing |
| Security features | Standard level | Standard level | Not specified |
| Colour | White with black gaskets | White | White |
| Profile reinforcement | Solid steel reinforcements | Basic reinforcements | Not specified |
| Warranty | 3 years | Not specified | 2 years |
| Lead time | 4-6 weeks | 8-10 weeks | 12-14 weeks |
| Total price | €215 | €180 | €140 |
From our experience, when two offers look similar in all of the specifications, it’s better to choose the one with clearer installation arrangements, better after-sales support and a longer warranty.
Red flags and green flags
To sum up, it’s the details that show whether a quote is reliable or could lead to complications later. So what is really worth checking?
Red flags: missing Uw or Ud values, no clear scope of installation works, no information about disposal of old units, price given without technical specification, unclear warranty terms, or no handover protocol after the works are completed.
Green flags: a complete technical specification, clearly described sealing or installation layers, simple handover checklists, a transparent service procedure, and very clear information on who is responsible for installation. A good quote should explain whether fitting is included or handled under a separate agreement, what the installation warranty covers and what the exact cost is.
Even if you understand the good and bad signs, comparing several quotes can still feel a bit overwhelming. This is why we always suggest going through the offers together with a specialist. Hubert, who leads our Quoting Team, adds:
‘’We would advise the customer to come back and consult their offers with us. We can review them together, configure our own proposal and clearly explain the price differences. In most cases, this is because with us the customer receives a product that is almost fully specified – a full-option configuration with all the important upgrades already included.’’
How to compare window and door models quickly and easily?
As we’re coming to the end of this guide, there is one more thing we’d like to pay attention to. Exclusively for our customers, we have prepared a Fenbro comparison tool on our website. While you wait for your quote, it is a fast and easy way to get an initial overview of selected window and door systems. Check the infographic below to see how it works.
Conclusion
We know how confusing it can feel when you have a few different quotes in front of you. It’s totally normal to look straight at the price and think: ok, which one makes the most sense?
But this is usually the moment when it’s worth slowing down just a little. The differences can be hidden in the small things we wrote about – Uw value, glazing type, hardware, overall build quality. It’s easy to save at the beginning, harder to fix later.
If you’d like a quote that’s clear from the start and easy to compare, please feel free to get in touch with us. Fenbro Quoting Team puts real effort into preparing offers that make sense in practice (not just on paper) and we’ll happily guide you through the options to find the best fit for your home and your budget.
FAQ – comparing window and door quotes
Is the Ug value enough to compare window offers?
No. Ug refers only to the glazing unit. When comparing quotes, you should always check the Uw value, which shows the thermal performance of the whole window.
Is warm assembly always necessary while replacing windows?
Not in every situation. However, proper sealing principles and correct connection between the window and the wall are always important for durability and energy efficiency.
Why can one window quote be 20–30% cheaper than another?
Usually because the specification is different. Lower prices may result from simpler glazing, basic hardware, reduced scope of works or missing elements in the offer.
What should be clearly stated in the order or contract with the window and door company?
The document should include dimensions, product system, glazing specification, price breakdown, payment terms, delivery timeframe and warranty conditions.
How can I compare quotes if the number of windows is different?
Try to calculate the price per single window of similar size and configuration. This makes comparison much more accurate.
What about window sills and finishing work?
These elements are not always included in the base price. It is worth checking what is specified in the quote and what may be treated as an additional service.
How can I recognise an underestimated window installation scope?
Warning signs may include very general descriptions, lack of details about sealing methods or missing information about preparation works.
Should I always choose the cheapest quote when buying windows and doors?
Not necessarily. A slightly higher price may reflect better technical parameters, clearer documentation or more predictable project execution.
Do opening systems influence the price?
Yes. Different opening mechanisms and hardware solutions can affect final cost.
Is warranty length the most important factor?
Not exactly. Length is important, but rules of warranty matters more. It is necessary to understand what is covered and how the service process works.
