Why you absolutely must get 3 quotes for triple glazing

Installing triple glazing is an investment that will increase the value of your home, as well as your enjoyment of your home. But it is also a sizeable financial investment, so you should make sure that you do your homework thoroughly before appointing a contractor. Ask around and do an internet search in your area before you get reputable companies to give you estimates on the proposed work. Then compare these quotes and make your decision. But it’s not only the price of the job that should be considered. Here is why you should get at least 3 triple glazing quotes before you upgrade.

What should be included in the quote?


The quoted price should always specify the exact materials that will be used in the manufacturing of the units. In triple glazed windows, these materials consist of 3 glass panes separated by two gas-filled spaces. The glass will range from 3 to 10mm thick but is usually 4mm thick, and may be laminated or tempered. Especially the central pane must be strengthened to increase its resistance to thermal stress cracking by 4 – 5 times.

Triple glazing uses low emissivity or low-E glass on the inner pane. Low-E glass is covered with a microscopic layer that reflects long wave infrared energy, or heat, back into the home instead of allowing it to escape to the outside.

The glass should also be specified as low-iron or extra clear. Extra clear glass allows short-wave solar gain into the house, allowing for the maximum of light to enter the home. All of this must be specified on your costing so that you can be sure what is included in the price. Different triple glazing suppliers have different names for their own brand of low-iron glass, so you should ask them about if it isn’t clear from the quote.

The type of frame will also influence the cost. A traditional wooden frame or composite (aluminium-clad) is more expensive than aluminium, with uPVC being on the lower end of the scale. Your quote should specify whether labour and delivery is included in the cost or not, and if there are any additional charges related to your specific installation. Any exclusions on the quote should be clearly indicated.

It is important to note that the contractor is responsible for the necessary insurance for the workers and liability insurance in case something is damaged. You may also be charged for the use of special installation equipment like cranes or scaffolding.

The quote should clearly state the guarantee that comes with the product.

The guarantee should protect you from the financial liability of manufacturer’s defects, gas leaks, and future cracks in the glass or frame. The size of the guarantee is generally reflected in the cost, so make sure that you read the fine print and know what is covered and what is not. Some guarantees are also not transferable which could influence your choice of contractor if you are renovating with the intention of selling.

How to find the right contractor

It is always best to find a local contractor because a closer proximity to site allows for better after-sales customer services. When selecting a contractor, ask for testimonials or ask other home-owners in your neighbourhood for recommendations. An internet search will also give you a lot of information and reviews on your shortlisted suppliers.

How to compare a quote


1)     The quoting process

Will give you a good idea of the quality and level of service of the relevant companies and should be the first thing to compare. How quickly did they respond to your request for a quote? What was your experience with the representative? How soon after the initial visit did you get your costing? These are excellent indicators of the level of service you can expect once you choose your triple glazing manufacturer.


2)     Price range:

An installer can’t give you a price range without surveying the property first. Your installation costs will vary based on where you live, the size and quantity of the windows, the accessibility and ease of installation, and the type of frames you want.

Considering all the variables, it is difficult to give an estimated cost of replacing all your windows with triple glazing. But as an indication, a two-bedroom flat will typically need four windows replaced at a cost of £1,950. A two-bedroom terrace house usually requires five window replacements at a cost of £2,500 while a semi-detached house typically requires seven replacement windows, for which you can expect to pay between £3,400 and £4,400. A standard detached house will generally require between 12 and 15 new windows which will cost between £6,000 and £7,000.


3)     Guarantee comparison

A guarantee should cover more than the window themselves, and deal with issues such as frame cracks and discolorations and most importantly, gas leaking from the insulated cavity. Over 25 years, the most typical failure of a triple glazed window is the seal, so make sure that your guarantee covers this.

Some companies, although rare, offer a lifetime guarantee on all windows. A standard guarantee will make provision for a 10- year guarantee on uPVC, wood and aluminium frames, and 5-year guarantee on stained wooden frames. The gas seal typically has a separate guarantee, of which 15 years is the average.

In general, triple glazed units last between 10 and 25 years, and therefore one should search for a warranty of at least 10 years.


4)     Materials

Three different materials may be used for triple glazed windows. Although wood is the most expensive material, it lasts the longest when properly maintained. To make sure that your new windows are environmentally responsible, all wood elements should be certified as sourced from sustainable forests. uPVC and aluminium are two more cost-efficient options to consider, but their impact on the environment is greater. Whichever material you use, make sure that it is properly sealed, and doesn’t contain cracks that will let the heat out, or cold air in.


5)     Thickness and weight of the units

These recommendations will include improvements like insulation of roofs, installing triple glazing to improve the U-value of windows, insulating floors and walls, installation of energy efficient appliances and upgrading of an outdated heating system.

Why it is essential to get 3 quotes

When making a major purchase, it is necessary to shop around. You wouldn’t buy a car without getting comparative quotes. Likewise, you shouldn’t accept the first quote offered for a major home renovation like triple glazed windows. Getting 3 quotes will give you a feel for what the average price should be. An unusually low or high quote will only be evident when you can compare it with other quotes.

Contractor’s quotes ultimately involve 3 steps: The first step is getting comparative quotes from 3 or more contractors. The second step is understanding what is and – more importantly - what isn’t covered by the quotes. The third, is to compare the quotes on a level playing field.

Be suspicious about 1 quote being significantly lower than the rest. If one quote is lower, this may be because the cost of installation and delivery isn’t included, because low quality materials are being used, or because the insurance policies are not sufficient. Getting the best deal shouldn’t come at the expense of your home.

Remember to always check a contractor’s reputation. A contractor with low prices but less than stellar recommendations but should never be used. You get what you pay for, so make sure that you’re paying for the right triple glazing for your home.

Published on : 7th February 2017

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