Sash Windows Logo

The Symphony Window

Our premier Bygone sash window is probably the best PVC-U sash window available in the market place. The Bygone Symphony succeeds when “only the very best” will do. As you might expect, this range has virtually every optional extra fitted as standard. And is now available with FINEO vacuum insulating glazing and a U-value of 1.2.


Wood grain textured acrylic foil on all profiles with every corner has a traditional, vertical and sealed, “butt jointed” construction, providing the perfect appearance.


Our exclusive ‘Super-Slim’ 39mm external Transom, a ‘Bygone only’ feature, sure to turn heads and impress even the most discerning conservation officer.


WER “A rated” with slim line 18mm sealed units, containing Krypton gas allow deeper internal Georgian bars and glazing beads, whilst chamfered external bars provide the traditional ‘putty-line’ glazed appearance.


Fully steel reinforced sashes and added security from the exclusive stainless steel Bygone clawed cam catches, means Symphony is fully “secured by design” compliant making it police approved and the preferred specification for sash windows.

Window Styles and Key Features

To help you visualise what your new sash windows will look like, we’ve listed some of the more popular window designs to give you some idea of the variety available. The design of the Georgian bar layout changes the appearance of windows, so it’s vital to select those that match your current windows or those that existed previously.

Now Available with FINEO Vacuum Insulating Glazing

Symphony is already widely acknowledged as the most authentic timber alternative sash window on the market, its unique and beautiful features enhance the product in such a way that nearly all who see it close up think it’s timber. With the addition of FINEO’s advanced technology, this amazing product has taken a giant leap in replicating that of a traditional timber single glazed product. Combining exceptionally high thermal insulation with impressive soundproofing and unseen durability, insulating just as well as triple glazing, but lighter and thinner with the aesthetics of single glazing.

When it simply must look
like timber

Symphony windows are designed to satisfy the requirements of modern windows and to comply with current building regulations.

However, the first requirement is still for the windows to blend seamlessly into their surroundings and to retain the character, charm and period feel of your home.

But don’t take our word for it, have a look at the video of a recent installation of Symphony Sash Windows.

Integral Mullion

Look at any other manufacturer of PVC sash windows, you’ll find bulky coupled frames or single windows screwed together.

Our new slim line integral mullion, changes that completely. All Symphony windows are now coupled with this new mullion, reducing the bulkiness by more than 50mm and reproducing elegant multilight windows, of superb proportions, just like wooden windows.

Timberweld® Construction

Timber sash windows have traditionally been made with vertical “mortice and tenoned” joints for hundreds of years, however joints in PVC-U pose very different challenges.

Every corner on Bygone Symphony windows has Timberweld® traditional vertical joints, which along with a  wood-grained, textured acrylic foil provides the perfect authentic sash window appearance.

Whilst the standard offering is white, cream coloured foil is also available. If you require something a little more special, then why not consider the contrast of black frames with white sashes, or any “Farrow and Ball” or “RAL” chart colour bonding.

Super-slim 39mm Mid-rail

Previously the mid-rail on a sash window has presented a particular problem due to the PVC-U profiles needing to be a minimum of 52mm in order to not only have the strength to hold the glass in the tops sash, but also to accommodate the required room for steel reinforcing.

The Bygone Symhony introduces an industry first for PVC-U sash by introducing a ‘Super-Slim’ external mid-rail measuring an astounding 39mm. Whilst only being a difference of 13mm, the aesthetic difference is striking, making the Symphony almost indistinguishable from it’s timber counterpart.

The internal 62mm meeting rail has also been exchanged for a much slimmer 52mm, creating slimmer sight lines whilst leaving enough room in the profile to accommodate steel reinforcing for the bespoke furniture to be secured to.

Slender sealed units with extra deep bar and bead

While all our windows are steel reinforced, secured by design and “A rated” as standard, Symphony has slender 18mm sealed units, filled with Krypton gas.

Krypton gas performs far better in narrower units than more common chunky double glazed units and allows the internal aesthetic of the window to have really deep astragal bars and glazing bead.

Interlocking Georgian bars form a grille which is firmly attached to the glass surface, while the bar ends are clamped in place using patented, stainless steel Georgi-clips.

Externally chamfered sashes and bars provide the traditional, “putty-glazed” appearance.

Colour suited locks and recessed limit stops

Every Symphony sash window is fitted with either a single or a pair, of solid stainless steel cam catches and face fixed keeps. Unique to Bygone, a pair of left and right-handed cams will centralise large sashes within the frame for better security, Even single cams are attached with 3 screws so they can’t be forced apart.

Every keep is attached with 4 screws, 2 for vertical alignment, and 2 horizontally into the steel reinforcing. Each keep is also fitted with a special nylon insert to protect the plated surface of the stainless steel claw.

All sash windows have a pair of uniquely recessed limit stops, these are silky smooth and do not protrude from the surface of the sash until open.

Find your Local

Our MASTER INSTALLERS are a team of specially trained craftsmen, selected by us, to deliver a quality installation of your chosen Masterframe windows.

Download a Brochure

Download our Bygone brochure or get in touch to have one sent in the post.

Download Brochure

Installed by Master Craftsmen

Our installers are fully trained and chosen for their skills in delivering a quality installation. If you would like to find out more about our Master Installers please click here.


You can view a virtual showroom tour of our wide range of quality products which we supply from leading manufacturers all from the comfort of your own home.

View showroom

Design, price & buy your uPVC windows online. Design your ideal windows online using Price Master  Window Designer and, once you’re done, get a quick and easy quote.


Our unique London Sash and Frame system. It is perfect for replacing timber windows with an arched exterior and square interior, commonly found in Victorian buildings in London and the surrounding areas.

Find out more