10 questions to ask your double glazing installer


Finding a high quality double glazing installer whom you can trust isn’t as difficult as you may think. It just requires a bit of research and a set of decent questions.

With this in mind, here is a list of 10 questions for you to ask any potential double glazing installers you approach so that you can weed out the master builders from the cowboys.

1. Why should I do business with you?

If a double glazing installer can’t convince you of the reasons why they are the best company to complete your project, they aren’t worth your time or money. Questioning an installer about their unique selling points will help you gain an idea of the benefits of trading with a particular company over another. This will help you find the business best suited to carrying out your installation.

2. What is the trading history of your company?

Finding out about the trading history of a double glazing installer will give you a good idea of how trustworthy they are and help you to minimise the chance of dealing with a ‘boom and bust’ home improvement company.

Like many industries, the home improvement industry suffers from its share of ‘boom and bust’ companies: businesses that go bankrupt, change their name and start up again.

An installer who provides hazy details about their past and refuses to give specifics about turnover, their history and previous projects could be hiding important information about previous bankruptcies or scandals.

If a company has declared bankruptcy, it’s usually representative of a wider problem in the way that business is run: whether that issue is one of financial mismanagement, lack of capital or something else. Steering clear of companies that can’t provide solid details about their history is a good way to protect yourself against these zombie companies.

3. What accreditations do you have?

Accreditations are awarded by independent, third party certification bodies. They show the ability of a double glazing installer to meet a required quality standard in their installations. They can also show the ability of a product to meet a particular set of criteria, such as enhanced security or energy efficiency.

Accreditations can be thought of as the ‘stripes’ and ‘medals’ of a home improvement company. If a soldier has lots of high quality medals and stripes, chances are they have proved their abilities and prowess and have a good reputation. Likewise, if a double glazing installer has lots of high quality accreditations, it shows that they have proved their skill and craftsmanship, and that they have a good reputation in the industry. Looking at the accreditations of a company will allow you to assess their skills, service and industry-reputation before even having to deal with them.

4. Tell me about your product range

A good double glazing installer will know their product range inside out. They should be able to tell you specific information about any window, door or conservatory that they offer. This information can take the form of technical data about a product, such as U values, WER ratings (Window Energy Ratings) and weather-resistance values, to information about available hardware, furniture and colour options. A double glazing installer that is able to give you detailed information about their product range is more likely to deliver a better quality installation, than one who doesn’t.

5. Do you directly employ your own staff?

Similar to the situation in many industries, outsourcing labour in the double glazing industry has started to become popular. To cut down on labour costs, many double glazing installers will contract out projects to other installers, paying them to complete the installation for them. This presents a problem because it means you can’t be completely sure of the background, skills, and experience of the installer completing your installation. In the event of something going wrong, it also makes that installer harder to trace and bring to account.

At Win-Dor we never subcontract jobs, and directly employ all of our double glazing installers. We carefully assess and develop the skills of our staff so that you can have complete faith in the quality of our installations.

6. Do you offer an Insurance Backed Guarantee (an IBG)?

Since 2015, Insurance Backed Guarantees have become a compulsory service that all installers, regardless of their company size, must offer with installations. By checking whether or not a double glazing installer offers one you can make sure that they are trading legally. Insurance Backed Guarantees protect you in the unlikely event of the company you’re dealing with going bust or running into financial difficulty. An installer who doesn’t offer one is breaking the law.

7. Do you only accept cash payments?

A double glazing installer who only accepts cash payments should be avoided at all costs. Although technically legal, trading only in cash is considered extremely bad practice in the construction and fenestration industry and will raise eyebrows.

This is because cash payments make it easier for cowboy builders to avoid paying their due amount of tax on installations. It also makes it easier for them to keep hold of your money if something goes wrong with the project.

In this day and age it’s much easier, and much safer, to use other forms of payment, such as cards and cheques that provide some form of reference, to pay for home improvement products.

8. Do you use gimmicks?

An installer who uses gimmicks should be avoided at all costs: gimmicks can often be used to hide the poor trading practices of an installer.

Flashy gimmicks and cheap deals can look attractive to begin with but can often end up costing much more. Always be aware of them, and check with your installer to make sure that they don’t engage in this kind of bad practice.

9. Will you fix a problem after installation?

Finding out if an installer will fix a problem after an installation before work actually starts is a good way to guard against any unexpected costs. Homeowners who experience problems after installation can often be under the impression that installers will fix the problem free of charge when many won’t. Find out if your double glazing installer offers an aftercare service or a repair service, and if this is included in the price of your installation to prevent any nasty surprises.

10. Do you have a showroom?

The showroom of a double glazing installer is the perfect place to visit for some home improvement inspiration. Showrooms are simply a place where installers provide samples of their windows, doors and conservatories in example installations. They allow you the chance to examine the installer’s installation skill, see the breadth of their product range (and thus, their skills, knowledge and expertise) and also try out any products you’re interested in, before investing in them.

A good double glazing installer will most likely have a well-stocked showroom to show you. At Win-Dor we have three: Milton Keynes, Bicester and Northampton.

Improve your home today with Win-Dor

Win-Dor have improved thousands of homes across Milton Keynes, Bicester and Northampton. To find out more about our windows, doors and conservatories by calling us on 01908 233 433 or sending us an email.