Replacement windows and doors - what to consider

Replacement windows and doors - what to consider

New windows are a priority for many home renovators who want to improve insulation and acoustic control, while also adding contemporary style to an older property. Choosing the right replacement windows is key, as windows play an important role in reducing your energy bills, provide security and a better indoor climate. If you’re planning to change your existing windows, here’s some helpful advice from our expert team.

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At VELFAC we understand that every property is different, which is why we provide everything from quality replacement windows with one, two or three sashes to single patio units with one glazing bar. All the windows we supply have been accredited to meet several national and European standards and are made from several materials to ensure they’re as durable as possible.


The economically sourced wood from northern-Europe provides a strong outer frame, while the aluminium sash guards against wind and rain – giving each unit a shelf life of around forty years. Our specially-crafted VELFAC quality windows also provide wonderful views of the great outdoors and the thin frames let in as much natural light as possible – helping to improve the energy-efficiency of your workplace or home.


The unique composite structure of our products means they require little to no maintenance – making them a great investment. VELFAC aluminium / timber windows are virtually maintenance free, and have an expected lifetime of up to 50 years.

What should I think about when replacing windows, especially if I want to install larger windows?


Our guidance is always to talk to your builder, architect or VELFAC Approved Partner before any window replacement project; VELFAC system is different from others on the market and there are some important aspects to consider.


Issues to consider include:


  • Structural stability – a ‘high performance’ window may be heavier than the window being replaced, and so walls must be able to support the additional load. This is especially the case with triple-glazed units which can be significantly heavier than older units (making them unsuitable for some refurbishment projects).

  • Depth of frame – composite glazing, such as the VELFAC system (which combines external aluminium with inner timber frames) are often thicker than older window styles so the impact of the different frame construction needs to be assessed.

  • How to prepare the window opening – most window suppliers ask for openings to be prepared according to specific guidelines. A window installer can survey your property and advise on how the opening should be prepared, but will expect the work to be completed by your builder ahead of installation.



I want to install more and bigger windows – how can I make sure they suit the style of my home?


The trend among self-builders and renovators is definitely to increase the ratio of glass to wall in a home. Making sure that new and larger windows are in proportion with the style of your home is very specific to the individual project, so we advise consulting an architect to ensure your plans are realistic and won’t negatively impact the appearance, performance or the value of your home.


Larger windows can also have a significant impact on daylight and solar gain – ‘free heat’ from the sun can be a real benefit in terms of reduced energy bills, but can also become a problem if not managed effectively, especially in an older property originally designed with smaller window units. To ensure every room in your home is comfortable all year round, consult an architect or window expert. They can advise on the ideal size, location and combination of windows depending on the orientation of your home, the position of individual rooms, and the amount of local shade (and its impact at different times of year).



What building regulations apply when replacing glazings?


In most cases, if you are just replacing older windows and are using a FENSA-registered installer, they will be approved to carry out the work to comply with Building Regulations without involving building control.


An application to building control needs to be made when the new windows are bigger than the existing opening or if you are planning a more complex alteration or refurbishment of your property.



How easy it is to replace windows with sliding or french patio doors?


Sliding / patio doors often require extra-wide openings and so – as for large windows – structural considerations are important. Again, ask your builder, architect or window installer to advise on issues such as:


  • Load - the wall above must not transfer any weight or load onto the door. Load calculations are also required to ensure minimal glass deflection when the door is installed.

  • The base for the door - a solid base is crucial as unstable grounds can lead to issues with door alignment and operation.

  • The ideal style of bottom track – for example, if you want a flush track can the base accommodate a pocket sunk into the ground? Flush track options are also vulnerable to driven rain or high winds, so a low profile threshold may be more suitable for exposed locations.

  • Space – folding doors can create extra-wide openings but need external space to store the individual door panes when open; if space is limited then a sliding door could be a better solution.



What's the right frame material for replacement windows?


Before buying replacement windows, it’s important to know as much as possible about the material they’re made from.


uPVC windows: are low-maintenance and cheaper than other replacement windows. Upvc windows however usually feature a thick frame which cut down natural light in your house and reduce acoustic insulation.


Wood: Timber is sustainable choice and the best insulating material for replacement windows . Wood is however the material which is most affected by elements and require regular maintenance and painting.


Aluminium: Robust and resistant to rust, this is the optimal choice if you are looking for hard wearing, modern looking replacement windows and doors. Aluminium however is not a good insulator, so please be aware of this when considering which replacement windows to buy.


Composite windows are built using the best of two materials: the internal wood acts like a barrier for heat which doesn't escape out and the external aluminium provides beautiful, low maintenance, long lasting modern windows for you to enjoy up to 60 years.



Replacement windows: double glazing or triple glazing?

With single glazed windows no longer meeting building regulations on thermal performance, the choice for your replacement windows will be between double or triple glazing. Both double glazing and triple glazing replacement windows have some pros and cons. Certainly the third layer of glass featured in triple glazing units an exceptional level of thermal efficiency, which helps to keep you home warm during winter. However we always suggest to consider a whole house approach, and opt for a mix of triple and double glazing depending on the position of each room to the sun, the level of wall insulation and solar gain. To learn more about benefits of choosing windows with two or three layers of glass , please read out blog



How much do replacement windows cost?


Replacing your old windows can be an investment, and the cost will depend on many factors such as if you are opting for a full window replacement or just a few units, on the window size and type of glass and of course on the material you choose. Choosing the right type of replacement glazing for your project can make a big difference to the comfort of your home, your energy bills and your ongoing maintenance costs , so we suggest to consider the whole life cost rather than only the purchase price. VELFAC composite windows are made to measure and on average the price per sqm is £450, which can decrease depending on the size of the project. To learn more about your new windows price and discover all the benefits in terms of thermal efficiency they can bring , please contact us for a now obligation quote.


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Find inspiration in our catalogue

Discover all the benefits of VELFAC by downloading our catalogue Windows for life - the ideal starting point for choosing the right windows and doors for your home.


Play with colours and window types

If you prefer a “hands on” approach, try the VELFAC visualiser. See how different doors and windows work on different types of houses and get inspiration for your own project.

Explore our photo gallery

Browse our gallery to see VELFAC windows and doors installed in many different projects – from modern new build houses to extensions and renovations.


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Made to measure

When you choose windows and doors from VELFAC, you can be sure that the sizes fits your home. They are made to measure.


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