Window Fitters in Harrow, Greater London (22)

Ahead of your window replacement, there are various steps you can take to prepare your home and ensure everything goes smoothly:

1. Clear the area around the window(s) both inside and outside

2. Remove any window coverings, such as curtains, blinds, or shades

3. Check for existing damage around the window frames that you might need to highlight to your fitter

4. Cover floors and furniture with dust sheets to protect them from dust and debris

5. Confirm your requirements with your window fitter to make sure you’re both on the same page

6. Be prepared for some disruption as window installations can be noisy and create dust and dirt inside and outside your home

   It’s also useful to check the weather forecast ahead of your window replacement. If the weather is particularly bad, it may delay the installation process.

No. As a general rule, you don’t need planning permission to replace windows in the UK – especially if you’re replacing like for like.

However, there are some exceptions where you might need to apply for planning permission, which include:

• The property is a Listed Building – If so, you'll need listed building consent to replace windows, even if they're like-for-like replacements
• You’re in a Conservation Area – You may need planning permission, especially if the new windows significantly alter the appearance of the property
• You’re creating new window openings – You’ll usually need planning permission for brand-new window openings in a property
• If in doubt, speak to your local planning office to confirm whether your replacement windows require planning permission.

Building regulations

Even if you don't need planning permission, your replacement windows will still need to comply with current building regulations.

The best way to do this is to hire a FENSA-registered window fitter to do the job who will have the skill and knowledge to comply with building regulations.

Ready to find reputable FENSA-registered window fitters working in Harrow? Read our tips on how to find the best window fitters near you.

If they’re in good condition, you should be able to keep your old window frames.

However, it’s usually better to replace both the window frames and the glass together. That way you ensure a higher level of insulation and energy efficiency.

If you’re hoping to keep your existing window frames, here are some key points to consider:

• Condition of the frames – This will be one of the key factors that will dictate whether you can keep your old frames as they’ll need to be in very good condition
• Energy efficiency – Modern window frames are designed to be energy-efficient and often old frames just can’t offer the same efficiency
• Building regulations– You may find that your local building regulations require you to replace the entire window to comply with energy efficiency standards

The best way to find out if you can keep your old window frames is to speak with window fitters covering Harrow.

Double glazing is extremely popular with homeowners in the UK, and for good reason. Here are some reasons why you might want to consider double-glazed windows:

• Improved energy efficiency that will see your property lose less heat in the winter and stay cooler in the summer
• Reduced noise pollution from outside sources, such as street traffic, passers-by and neighbours
• Better security – Modern double-glazed windows are often fitted with high-security locks and toughened glass that makes your home more secure
• Reduced condensation – Say goodbye to unwanted condensation, mould and mildew on the inside of your windows
• Long-term savings – The initial investment may be high but your long-term energy savings often outweigh the cost
• Choose a style to match your home – Double-glazed windows come in a variety of styles and finishes, so you can pick the perfect choice for your home

Want to know more? Check out our dedicated guide to double glazing.

The cost for double glazing in a four-bedroom house in the UK usually ranges between £5,000 and £10,000. That estimate includes full replacement of standard UPVC windows across the property.

Read more in our guide to double glazing costs.

Technically, yes. But in most cases, it’s not advised unless you have professional experience. Double glazing installation requires accuracy, skill, knowledge of materials, and understanding of building regulations.

Plus, if your installation isn’t FENSA certified, you’ll also need to apply for Building Regs approval yourself. This costs money and can delay the project.

Yes, in most cases it is. If your windows are more than 20 years old, you might be dealing with draughts, condensation, sticking frames, and poor heat retention - all of which can be solved with a new set of double glazing.

Today's double glazing units offer better energy performance (especially with A+ or triple glazing), enhanced security features, and longer-lasting frames.

What to consider:

• Are your current windows cold to the touch in winter?
• Do you see condensation between panes?
• Are your energy bills high?
• Can you hear a lot of outside noise?

If you answered yes to any of the above, it may be time to find replacement windows and request quotes from window fitters working in your area.

While there is no national scheme open to everyone, you may be eligible for help through:

• ECO4 scheme: Offers support to low-income households to improve energy efficiency, including windows.
• Local Authority Flexible Eligibility (LA Flex): Managed by councils to help vulnerable residents.
• Home Upgrade Grant: Aimed at off-gas grid homes with poor insulation.

Most window fitters work all year round, but the best time to install double glazing can depend on a few things:

• Autumn and spring: Ideal for prep ahead of extreme weather.
• Winter: Fewer bookings may mean faster availability and discounts.
• Summer: Good for fitting but in high demand, so prices can rise.

If you're after the best deal, look out for seasonal offers. Many window companies offer discounts to fill their quieter periods.

There isn’t a single “best” for everyone - it depends on your home, budget and priorities. Large brands like Anglian and Everest are well known, but many homeowners choose smaller, local window companies for benefits such as lower costs, faster installation, and a personalised service.

When looking for the best window company for you, think about:

• Do they have good reviews from their previous customers?
• Are they FENSA certified?
• Do they offer guarantees?