A Guide to Buying Windows & Doors

You've decided you want new windows and doors to replace existing ones or you're planning for a home extension/new build. However, you've discovered that buying windows and doors is a minefield, of product choice, technology and terminology. You don't know where to start. Due to this, we've put together this 'How to' guide for buying windows and doors to help you through the process.

Our guide to buying windows and doors

Firstly, before you contact a specialist tradesperson it's good to try and get an idea of what you're looking for. This will help you direct the conversation and remain open-minded. As a result, you'll take on-board recommendations and considerations that you'll be able to ponder after the tradesperson has gone. What you should take into consideration are;

Piggy bank to illustrate budgetsInitial budget

First of all, buying windows and doors is not cheap. You need to know how much you have to spend on the project. Knowing this will help guide you through decisions that need to be made, e.g. product material, type, style, colour etc. Furthermore, it'll help you to keep control of the budget so you don’t end up feeling out of pocket.

As with any project, there can be budget drift, e.g. when you upgrade products and features beyond the initial plan. Therefore it's always a good idea to have a bit of a buffer in the budget. To get a realistic understanding of a required budget take a rough note of sizes and styles of your windows. Some tradespeople may be happy to provide a rough cost over the phone or via email if you're able to give them the right information (sizes, style, colour etc).

Most tradespeople prefer to visit the property as there are many factors which affect the cost of installation. For example, the state of the external and internal walls, if the property is brick or pebbledash etc. They like to talk to the people involved to get a better understanding of the requirements. Independent tradespeople that come to quote are experts in their field and are hands-on when it comes to installations, therefore, they're a font of information that can be tapped for advice and what to look out for.


It's a good idea to put in some leg work, really nail down what you're looking for. There are a few places you can begin;

  • Scout around to see what type of windows and doors the neighbours have to see;
    • What you like
    • Write a list of likes, dislikes and any queries/questions that you may have
  • Do some research online. I suggest the following depending on how thorough you like to be;
  • Find factories and/or showrooms in your area which you can visit to see the products and components in the flesh. This is also an opportunity for you to pick the brains of an expert. Due to COVID-19, you’ll need to look online. Check out company brochures and contact them to request more advice/information
    • You can ask them about energy ratings, the potential benefits versus cost or the different hardware options etc
  • Check out tradeshows or home exhibitions taking place. The FIT show takes place at the NEC in Birmingham in May

A man measuring a window to quoteQuotes

What to prepare and what to find out

It's good practice to get 3 quotes for your project. I would recommend the following;

  • Write down and draw out exactly what you're looking for. That'll help you receive like for like comparisons from three tradespeople
  • Prepare a list of questions that you want to know about each company. These might be;
    • What are their terms of business and terms of payment?
    • Ask about the type of guarantee do they offer and what does it include?
    • Do they offer an insurance backed guarantee?
    • Which competent person scheme do they register the product with (it does not affect product or service, however, is always good to know)?
    • If you order the product from them, what are the timescales that you would be working to?
    • Do they have a pre-installation routine that you need to adhere to, for example, moving furniture or ornaments etc?
  • Take notes of the information and recommendations that the tradesmen are giving you. This may lead you to review the product or other quotes that you have received later on

How to manage it

Ideally, you'll get a price for the same product from each tradesperson, however, in reality, this can be tricky. It's normal for tradespeople to recommend different products or one doesn’t use exactly the same product as the others. This will cause the quotes to vary. In this case, make a note of any changes to research later on. That'll enable you to make an informed decision. You can ask the tradesperson to match the change or just take it as a consideration when comparing the quotes.

Once you've met with each of them you may want to write a list of what you liked and disliked about the quoting process and how you engaged with the tradesperson. You'll be inviting them into your home, therefore it's essential that you build a rapport with them.

Creating the contract

Once you've chosen a tradesperson and confirmed that you want to go ahead with a quotation you'll normally expect them to make an appointment with you. This will involve them visiting your property to take final measurements and confirm the product details with you before asking you to sign a contract.

At this point, it's not unusual for a homeowner to change their mind about the product details. This is easily done, however, be aware that it may increase the cost of the quotation. For example, if you change white handles to chrome the chrome handles will probably cost more. The more time that passes between signing the contract and approaching the installation date the harder it's to change product details, for example, the style of a window. Therefore make sure that you are firm about the product details at the point of order. Amendments may be able to be made later on, however they may come with an extra cost.

Cooling-off period?

Most of the tradespeople install bespoke, made to measure windows and doors. When you enter into a sales contract of this nature you don't have the right to cancel or a 14-day cooling-off period. The tradesperson may give you a 14 cooling off period if you ask for it, however, be aware that it will extend the timeframe of the work. Tradespeople won't order products if the homeowner can cancel them, as it'll leave them with unwanted items which are difficult to sell on or install elsewhere. Therefore if you're arranging with the tradesperson to have them installed within 3 weeks then a 14-day cooling-off period isn't realistic.

Survey and contract

The tradesperson will draw up a survey sheet with each window and/or door that you want, coupled with the measurements, product details, installation details (e.g. any plastering and making good that may need to be carried out) and total price. They'll then go through it with you thoroughly, along with the terms of the contract before asking you to sign and agree that you wish to proceed. Both of these should either be left with you in paper form or emailed to you (a text will suffice with the information on, however, there's too much information for a text to be helpful).

The terms of the contract should cover payment details. It's at this point that the deposit needs to be paid. It varies from tradesperson to tradesperson, however, it's not unusual that a deposit is paid followed by payment before and during, with the balance on satisfactory completion.

Man installing a windowThe installation

You'll be contacted by the tradesperson to arrange the installation date. They'll issue you with instructions about how they wish you to prepare the area, e.g. moving furniture, ornaments etc. At this point, they may require the next payment.

When the work commences it's important to maintain clear lines of communication with the tradesperson. This'll ensure that any obstacles which will extend the installation time and/or incur extra costs are understood and agreed by both parties in a timely fashion, avoiding any misunderstanding and confusion. For example, if you've not asked for the window boards to be replaced and they're rotten to the point that they fall apart, replacing them will incur an extra cost, the tradesperson will need to spend extra time and money replacing them.


Once completed and all parties are satisfied the balance for the project is then paid. Once the balance has been paid the homeowner should receive the guarantee from the tradesperson (if they offer one), the certificate from the competent person scheme that the project has been registered with (Fensa, Certass, BM Trada, building control) and an insurance backed guarantee.

The product, although low maintenance, needs to be cared for to maximise its lifetime value and for any guarantees to be upheld. For more information on how to do this download our maintenance guide here.

Tips from tradespeople

  • Make sure you do your research and have a solid idea of what you are looking for
  • Choose a company you can build a relationship with. Remember you are inviting these people into your home
  • Ask to see their portfolio of recent installations and samples
  • Replace as many of your windows and doors as possible as this will be less expensive in the long run
  • If you have any questions or concerns speak to your tradesperson as soon as possible, be clear and make sure you understand the response. Misunderstandings can be harmful and easily avoided. We can’t know everything about everything, therefore there isn’t such a thing as a silly question. Don’t hesitate to ask.


We hope this guide on buying windows and doors has helped. If you'd like any further help and advice, please don't hesitate to contact us.