Should I buy off-the-shelf windows?
Other companies might show a fixed cost for new windows where you can buy pre-made sizes 'off-the-shelf' in limited colours and materials. But, these windows don't take into account all the problems that can arise when fitting new windows:
- Many houses have windows that are not a standard size
- Frames are not straight due to building shifts
- You might want windows to open a certain way
- You might want bespoke easy-to-reach or secure handles
- Listed properties have limitations on materials, style and colour
The cost of a new window listed on a website might seem cheap at first, but these list prices usually don't include installation. All Everest window costs are for supply and installation.
Most importantly, not all uPVC windows are built the same. There is a wide range of difference in the quality of uPVC with the cheapest being susceptible to warping and discolouration.
Are cheap windows good enough?
Badly-fitted windows, and badly-done home improvements can devalue a property and negatively impact the house price. Poor quality windows leave you at risk from:
- Scratches on new frames and glass
- Poor quality uPVC can warp over time
- Incorrect frame sizes that need excessive expanding foam to force fit
- Bad installation that causes damp, leaks or draughts
- Double glazing desiccant - where the double glazing seal fails and you can see bits in-between the glass
- Condensation between the glass from poor or failed seals
- Fading on the frames
Cheaper off-the-shelf windows are often not a perfect fit and to make up for this an installer will use excessive expanding foam around the edges to fill in the gaps.
This can also cause damp, draughts and shorten the life of your windows.
Be cautious of new windows prices before an installer surveys your property – a reputable window installer will need to see your home before they can give an accurate cost of windows.
Can I install windows myself to save money?
In theory, DIY window installation can save on labour costs, but in practice it rarely works out cheaper for most homeowners. Installing new windows is a skilled job that requires precise measuring, correct fitting, and proper sealing to meet building regulations and avoid issues like draughts, leaks, or condensation.
In the UK, replacement windows must comply with Building Regulations (including thermal performance and safety standards). If the work isn’t carried out by a FENSA or CERTASS-registered installer, you’ll need to arrange and pay for a Building Control inspection and certification yourself, which can reduce or even eliminate any initial savings.
There’s also the risk of costly mistakes. Poor installation can lead to heat loss, water ingress, or even damage to the window or surrounding brickwork. All problems that may be expensive to fix later. In many cases, manufacturers’ warranties are also dependent on professional installation, meaning DIY fitting could invalidate your guarantee.
For these reasons, while DIY installation might seem cheaper upfront, professionally installed windows often offer better long-term value, performance, and peace of mind.
It's always recommended to buy new windows from a reputable brand company that install and supply, so that they take responsibility for a perfect fit and finishing.
