Sheerline Windows Review

In the first Sheerline Windows review, we take a helicopter view of the system and explore some of its features.  Garnalex Extrusions is behind the Sheerline brand.

The Sheerline Windows review. Background

There is a lot of window industry experience behind Garnalex and the Sheerline windows system. Prior to launch, the company, headed by Roger Hartshorn widely marketed that windows and doors had little innovation over the last few decades, and we didn’t necessarily agree. 

Not sure it’s seen “little development or innovation”? Flush casements, curtain walling, hurricane tested, structural glazing, bifold doors, minimal aesthetics, welded doors, more finishes/textures/woodgrains/foils, steel-look, automatic doors, hybrids, bigger sizes….. https://t.co/iKLfwBJ6Db

— AluminiumTradeSupply (@AlumTradeSupply) August 6, 2019

That said, their focus was clear. To design a new aluminium system, Garnalex felt addressed the issues faced by manufacturers and installers. The new Stellar aluminium system also has reduced the time spent making windows, as well as glazing and fitting times and brand new design.

Another reason behind the new suite of Sheerline Windows is the growth in aluminium. It is true consumer tastes in windows over the last decade have changed.  Slim lines, contemporary looks, colour options from stock, continued growth in patio doors, steel look. These remain current reasons aluminium remains desirable with homeowners.

However, any new brand in the fenestration sector faces some common issues, regardless of how good it is.  

• Getting any manufacturer to change system is never easy.
• Installers are similarly hard to convince to change what they sell.
• Homeowners are largely unaware of most brands of windows and doors.

You can have the best system on the market, but installers rely on good service from trade manufacturers. If this service is poor, installers will move on. Garnalex will provide the promised service – let’s hope any manufacturers of their product do the same. Systems companies have little control over the service their fabricators provide.

Will the homeowner like Sheerline?

If the last few months building up to the launch today of Sheerline are anything to go by, the company has an excellent team in place. Our belief is that any new system to have ongoing success needs to target the homeowner as much as the fabricator and installer.  

Up to now, we’ve only really seen trade benefits to Sheerline. The truth is, these apply to the trade only. How quickly a product takes to make or fit is of little importance to the homeowners buying aluminium windows for their homes.

Systems companies have, by and large, left the job of getting consumer awareness of their brand to the installer. All of them carry out substantial marketing but the focus of the majority is on the specifier market. There are some exceptions to this such as Reynaers and Origin – arguably two companies that have broken into the consumer market where homeowners and end-users ask for their products by name.

Ironically, brands like Schuco and more recently, Cortizo ride on the back of reputation. Manufacturers and installers love Schuco and some have even replicated the features of their products.  So where does this leave Sheerline windows?

Time will tell whether the aesthetics and design of this new window will appeal to the end-user market and whether installers will buy into it. Sheerline has its own unique selling propositions

Benefits for Fabricators and installers

We’ve no doubt Garnalex will be true to its word in providing standout service to its fabricators.  They promise a new way of dealing with a systems company, and they’ve invested substantial sums in getting every aspect of the process right. 

Sheerline tells us that Classic has been designed to be easier and quicker for installers and doesn’t require them to assemble frames on-site. The system features unique hinge receptors that hold the pre-glazed sashes in place, allowing for easy one-person fitting. There are also in-built toe and heel devices included.

They also tell us that the beauty of this patented corner construction method is that it’s a simple process to deglaze a sash on-site if required for changing the damaged glass.

And we’ve had it clarified that the sashes on the Classic system are to be pre-glazed. There will be differing points of view as to whether installers want pre-glazed sashes. There are service considerations, too. For instance, will the company be happy to provide glass such as integral blinds, and acoustic glass or use the free-issue units from the installer?

Design Features of Sheerline Casement Windows

Sheerline Classic now offers one of the slimmest aluminium windows amongst the leading brands.

Consistent with other well-designed systems, Sheerline has a choice of frame options.  There’s a flush casement product widely available on other systems. There’s also a contemporary stepped look you’ll find on steel-look windows and slimline casements.  It’s not a dedicated steel-look product, but looking at the section drawing that stops on the outside of the window is really pretty and neat. Everyone will like this detail and you’ll also find a similar look on the Reynaers SL38 suite and other systems.

Both windows look very attractive.  Beware the images on the Sheerline website showing the very slim outer frame. This will look great in new builds but won’t really suit window replacements. Typically these need a deeper frame or frame extenders. This is why the Prestige system, with a deeper frame, better suited for use with existing plaster reveals, provides a solution and an additional product here.

The product’s design and construction create neat corners thanks to the innovation we explain later in this Sheerline windows review.  Classic windows come with a full dummy sash design for equal sightlines.  Stellar Windows went the other way and designed a system giving consistent sightlines without dummy sashes and less material as a result.   

As you’d expect from the latest-generation new window is great security and excellent weather performance. U-Values are stated at 1.4Wm2K with a double-glazed unit. 

Both traditional or contemporary window designs come with the same outer frame option, resulting in less stockholding and invariably a lot of common parts across the entire system. 

Thermavic® is what the company refers to its multi-chamber thermal break design, insulating the high-grade aluminium extrusions. Multiple chamber thermal breaks aren’t that new, and used on other systems and Passivhaus windows already.

Three-part cill section.

The cill section is really quite clever. It’s a modular system where the back middle and front sections clip together. Therefore fabricators and installers use the back and the middle section as standard and a selection of cill noses at the front.

Cleverly, the cill comes with a co-extruded seal along the deep central section and the front and back. The purpose of this is to provide a good seal and means no more traditional mastic seal on the cill itself. The main centre cill profile will probably come in mill or anodised finishes as this won’t need powder coating.

What it also does is enable the back of the cill to come without an upstand and giving a flush look internally. Essentially the back of the window frame profile sits over the short leg on the back cill profile. No more cill upstands!

We can also see installers holding their own stock of this cill thanks to its modular design. It’ll address some common cill-related headaches on site.

An entirely new window design.

By far the eye-opening feature of their Classic window range is the absence of a glazing bead. Let’s address this surprising, but not new, design feature first. 

The windows come with a wrap-around design where the glass unit is entirely wrapped by the frame rather than set in it and held in place by beads.

The other innovation is the way the windows come together at the corners. We’ve examined the patent behind the system and it was applied for as early as 2018 and invented by Phil Parry. “A joint for a fenestration unit”.

The lengthy patent document stretches to over thirty pages but essentially, the windows have a wrap-around construction with the corners having an ingenious connected corner arrangement. This is an extruded section housing a specially designed connector. The connector design, comprising several component parts brings the corners together.

Small chevrons, several screws on each end and the connectors themselves draw the two mitres together, neatly and without the close scrutiny of the corner before you manually crimp it. As a result, the traditional mitre joint of the window doesn’t rely on the familiar corner cleats but a series of parts instead. It’s simple and yes, better than the traditional method of putting a window together. It also reinforces the claim of fewer parts and not just the omission of the glazing bead. 

Our only reservation, albeit small is whether fabricators and installers can get used to the wrap-around design, but full information isn’t available at the time of writing this Sheerline Classic windows review.

Is a bead-less window new?

No. There are many examples old and new of wrap-around glazing systems. From the Monarch residential doors and sliding doors. Vertically sliding windows.

For casement windows, there are systems from the late eighties and early nineties that came with a bead-less design. Glostal and Baco windows came with a wrap-around option. Even today the structural bonding of slimline sliding doors provides further examples of products without glazing beads. So it’s not new, neither is it revolutionary.

The beadless design is also removing the freedom from installers to use their own glass at their own prices. What we don’t know is whether Sheerline is allowing free-issue glass units with these windows.

So how do you glaze fixed lights on site? There’s no information from the company about how this is done. The only solution we can think of is a system only having dummy sashes. And as with the pre-glazed sashes the procedure is different. The sash is slotted into the frame using a different hinge method. Therefore, you’d fix the loose frame first, then clip in the glazed sash whether this is fixed or opening.

More benefits with Sheerline window corners

The first benefit is aesthetics. The lack of mitred or square cut beads on a window obviously improves the appearance and reduces the number of visible joints. It looks, neat and creates a better corner seal.

You’ll invariably end up with stronger window joints compared to crimping too. But for balance, the aluminium window sector isn’t plagued over the years with issues of splitting window joints either.  What is true is poor joints by bad fabricators where the client notices enough to reject the product.  But, Sheerline correctly tells us their design creates a genuine material saving in not having to scrap bad corners that a quality-conscious fabricator would probably do, in the same way they reject a substandard paint finish.

Additionally, handle a frame clumsily and window mitre joints do twist, move, split and water ingress issues may then occur.  The idea behind this new corner joint is brilliant, even though we’d suggest experienced and quality-conscious fabricators have for years produced clean, neat and well-sealed joints.  Credit to everyone behind this design though. They’ve eliminated the risk of a bad joint or ‘grinning edges’, known in the trade. 

Less reliance on expensive factory machinery

Another benefit of this construction method is less reliance on the crimpers whether mechanical or manual to bring window joints together. There’s also less reliance on punch presses too. 

Other benefits centre around the transportation of frame joints and kit-form windows. Mitred windows and doors rarely go to site unglazed for site assembly.  Square cut joints with brackets such as shopfront or curtain walling sections do. So while this is a benefit in not having to identify a bag of components to assemble a window, the reality is it doesn’t happen with residential casements. They’re factory glazed and assembled.  

Again for balance, Sheerline appears to offer a solution to the transportation of larger frames.  One side of the connector is already in the one corner, ready to receive the other.  So invariably there is less reliance on hidden or visible couplers to join a larger (assembled) window together. 

Bays, bows and integrated ancillaries

And finally, the inventor of this corner arrangement has taken into account that not every window corner is 90 degrees! And there’s a provision in the design where small gap sealant is used and assembly of the corner has to be quick before the sealant sets. 

We’ve not seen the technical manuals for the product yet, but it’s logical to assume that this type of window design requires fewer physical operations.  Cut the metal, prepare the ends for the connector and assemble the joint with the correct tool. The training of window operatives in assembling windows is less too – Sheerline windows as a system to put together after cutting needs less skill. 

Overall, we love this idea from a manufacturing viewpoint. Does it speed up production? Absolutely. Will it entice new fabricators to make aluminium windows without investment in punch presses and other machinery? Yes. The transition into aluminium just got easier for many still only making PVCu.

Installers will need to assemble frames instead of beading them.

Can you de-glaze a Sheerline window easily?

What is unclear as of now, is the work involved in years to come changing a failed glass unit.  We’ll update this Sheerline windows review once we can examine the system fully.

This design means changing a unit means substantially more work compared with removing glazing beads.  We know from experience, damaged and lost beads and discontinued systems remain an issue on older beaded windows.  Does this matter right now? Probably not.

Is a window without a bead more secure?

Of course, the system comes with full security testing such as Secured by Design. The lack of any bead makes for a very secure product indeed.  Sheerline call window beads “an area of weakness in traditional window design”. The truth is, for many years now, any weaknesses in window beads systems companies have designed out. Aluminium, PVCu and timber window beads are just fine! They’re easier to work with, easier to clip in and not a weakness.

It’s inevitable and obvious that Sheerline installers will sing the praises to the homeowner of how secure a window without a bead is.  We can picture the scenario in a showroom of a salesman next to this new bead-less window compared to the one beside it with beads. No doubt some will even use an unglazed sample to demonstrate just how worryingly easy it is to remove beads. The homeowner will invariably buy into something they can see and understand. They’ll love the security message around it and see a clear perceived benefit to Sheerline. And that’s great.

Some Balance about window beads

Once more we need to provide balance. Let’s remind homeowners that beaded aluminium windows, from most systems, are also Secured by Design, PAS24:2016 etc.  These windows have undergone and passed the same tests as Sheerline.  They have the same badges. Beaded windows remain just as secure and have been for many years already.  Of course, there are different classes of security.

The security claims are genuine. Sheerline tell us that two test houses couldn’t break the window, stopping before the damage to the rigs. Hinge protectors, bead-less design and the corner construction do make this the most secure slim aluminium window in its class. And unlike other designs, their lock doesn’t encroach into the bead pocket also a factor in giving extra security.

Colour options with Sheerline Windows. 

In this Sheerline windows review, we won’t touch on the colour options too much.  You’d expect in the current market any savvy systems company to offer a good range of standard RAL colours in stock.  

We are told by Sheerline that 11 of their stocked colours will be available in 5 working days. This benefit will trickle down to installers and homeowners in terms of responsive supply and the ability to get replacement product quickly. Its also the same lead-time on dual combinations of any of those 11 colours. That’s 121 colour combinations available in 5 days! This is great news for coloured aluminium lead times and even better news for dual colour supply.

For us, we are delighted to finally see a systems company brave enough to offer anodised finishes.  As a website, we are frequently contacted about this more durable, alternative way to colour aluminium windows.

We urge other systems companies and trade suppliers to take the step and offer anodised colours from stock. Market these colours correctly and they’ll be as popular in time as other colours. Hats off to Garnalex and Sheerline for offering the three popular Anodised Colours those of us with many years in aluminium will recall under Anolok, Sandalor and similar names.

Available Colours with Sheerline

• Natural Silver
• Mid Bronze 
• Black Anolok is what’s on offer right now.

Anodising is also the new method of pretreating aluminium before it’s powder-coated for those that didn’t know.

For RAL, you do get the expected popular range of colours with Sheerline windows.  

• Matt White RAL 9010
• Matt Anthracite Grey RAL 7016
• RAL 9005 Matt Black

There are colours Sheerline has chosen, some of which the established aluminium systems choose not to offer as standard such as:

• Cream RAL9001 Matt
• Agate Grey RAL 7038 Matt
• Squirrel Grey RAL 7000 Matt
• Turquoise RAL 6034 Matt 
• Brown RAL 8017 Matt. 

It’s a minor point but the vast majority of brown windows were painted in the past as BS 08B29 satin or RAL 8080 – rarely were they done in RAL 8017. Presumably, the company has done its research on what colours potential customers would like.  

Sheerline Windows Review – conclusion

We wish Garnalex every success with Sheerline windows and especially the unexpected turn of events with a global pandemic. The fenestration sector is closed right now and many potentially face an uncertain future. We congratulate the people behind Sheerline for pushing ahead with the original launch date, given the substantial effort and investment that’s gone into this new windows and doors range. They deserve to do well with this system. And it’s evident they’ve taken the time to look at existing systems and come up with something different and forward-thinking.

The design and aesthetics are new but not a million miles away from other recent windows on the market. The patented corner design and lack of glazing beads are the two things that genuinely set this system apart from others. Time will tell whether this bead-less design will challenge other windows on the market where all of them have beads. But the corner design is excellent with clear manufacturing benefits. The only murky area is how this system addresses the supply of unglazed frames by the trade to the installer and how strict a requirement for pre-glazed sashes is.

It’ll be interesting to see how installers take to pre-glazed frames and the different fixing method. The cill section is really good in it’s design and seeing innovation on these essential but rather staid part of a window is a nice touch. The anodised finishes for us is something installers need to look at but we also appreciate trends in colours are region-specific too and some won’t get why we should sell more anodised products generally.

The trade can look forward to a new and improved way of buying window profile thanks to the UK extrusion base, service and support. Any business striving to improve the fenestration sector and service overall deserves credit and support.

Don’t read too much into the marketing messages

There’s some great marketing behind Sheerline, but some of the messages could imply other windows are inferior. They’re not. Lets examine some of these marketing messages provided by Sheerline.

Reduced Site Visits

The company claims reduced site visits in the future. Any correctly made and fitted window generally doesn’t require future callbacks. And at some point in its life a window will need adjustment, even a Sheerline product. Yes, its installer-friendly in its features but poses potential problems in the future.

Many glass units (the glass itself not the window) only come with a five-year guarantee. Therefore, it’s worth a homeowner thinking about who services these windows when out of guarantee. Installer friendly.

No damaged or missing units

This really isn’t a problem for those installers with the systems in place to avoid missing units. Damages occur with unglazed windows as much as glazed.

The steel-look style

Whilst the balanced looks of Sheerline are attractive, the flush casement design is not a steel look. However, being fair there are other heritage flush sash systems on the market. The air MOD window comes with more versions than Sheerline too. Go with the window if you like its good looks, but it’s not a steel look system in the true sense.

Addressing square-cut beads and mis-aligned corners

Also in the sales message and sounding like a benefit is not having square-cut beads. As mentioned above, beads are not a bad thing and for future maintenance as well as glass replacement, a significant benefit over Sheerline.

There’s also a mention of the corner design reducing misaligned corners. Again, a well-made window doesn’t leave the factory with bad corners, assuming there’s a good quality inspection system in place at the manufacturer. Therefore, misaligned corners is bad manufacturing and not bad design.

Consistent Shadow Lines

The consistent sightlines are a neat touch. However, narrower fixed panes are equally attractive in a window. Moreover, not everyone likes consistent sightlines. In some ways these window designs and Sheerline is not alone, limits the design and aesthetic options available to a customer.

No draughts through a window cill

Silicone sealing is not a bad thing. It’s how neatly it’s applied that creates unsightly silicone on a window. The cill design of Sheerline is excellent. However, it’s claiming to reduce draughts though a cill. This has never been an issue with a correctly mounted and fitted window before.

Polyamide thermal breaks are just as good

The thermal break design in Sheerline is also very good and beneficial to installers. But they’re incorrect to mention condensation on bay poles and corner posts. Most systems come with a thermal break to these profiles as well.

Despite our support of secure beaded windows, the reality is that Sheerline can reasonably claim to have one of the most secure slim residential aluminium windows by design. And this security message will serve them well.