We’re the UK’s longest established, specialist, sash window manufacturer – they’re they only windows we make.

Maybe you have been manufacturing sash windows and are now looking to outsource or perhaps you are looking for a sash specialist to help grow your business. Whatever your situation, we’ll do what we can to help you and your installers win orders. If things don’t quite go to plan, we really do help sort it out. We’re just a phone call away.

As fabricators ourselves, we know the frustrations manufacturing can bring.

Balancing customer specifications with what you can physically produce is always a challenge. Low running stocks, suppliers who don’t understand your order and machine down time between set-ups can be a real nightmare. Why can’t customers sell standard windows? 

Making a sash window may take you several hours. In that time you probably could have made several casements, leading you to rethink your decision to keep them in-house. However, before you entrust another company with your client’s order, you need to be certain they will deliver, on time and in full.

Masterframe only manufacture sash windows


Customers are hard to find and even harder to keep happy. They expect you to hold everything in stock, in every possible colour and for it to be instantly available.

Competitors who claim to make better products – quicker and far cheaper – are always trying to steal your customers. It’s vital you satisfy your installers’ needs so they stay loyal. This means stocking a full range of casements, doors, patios and conservatories, but you don’t need to make everything. That would dilute what you do best, destroy your production efficiencies and increase your stock holding.

We don’t threaten your customer relationships; we want to increase your sash window sales.


We’ve worked with most of the large companies as they see the benefits of buying in sash windows, long term or contract specific.

We can supply your own brand of sash windows to suite with your casements. Imagine branded, bespoke products for your customers without the headache of making them, releasing valuable production time to capitalise on more profitable product lines.


We use two Schirmer machining centres to ensure accurate cutting of profiles, 24/7. In addition, we operate two four head welders and CNC corner cleaners, along with a host of other machinery. Set up solely for making sash windows, these guarantee excellent production standards, reliability and consistent quality.

There's no down time between machines. Computerised order handling, bar optimisation, cutting and bar coding means that efficiencies are extremely high, but quality even higher.


Masterframe delivers your windows with care. They travel to you in our own vehicles, as per your instructions. Our vehicles are tagged, so we can inform you of their progress and alert you if there’s a problem.

Your reputation is as important to us as it is to you. We deliver your windows on time so that you can keep the promises you’ve made to customers. In the rare instance that we miss something, it’ll be shipped overnight at no extra charge.

We are manufacturers ourselves, so we understand the importance of delivering to your installer network. It makes business sense for us to help you get sales, eliminate duplication of effort and prevent processing errors.

Regular clients can log in and see live quotes, add new ones out of hours and even send quotes to customers, direct from our system.


If you’ve never considered buying in finished frames, you’ll be reassured to know we come with excellent credentials:

  • Fabricator of the Year – twice winners of this prestigious award
  • Winners of National Fenestration awards for Timber Alternative Company, Fabricator/Manufacturer and New Product of the year for Timberweld®
  • Numerous Customer Care and Energy Efficiency ‹insert link›awards
  • Over 25 WER certificates, including the first five ever issued
  • The first PVC-U sash to gain Secured by Design accreditation
  • BBA certificates for the whole window – even the plant on Georgian bars
  • ISO systems and process controls across the business
  • CE marking for all standard products – as you’d expect.

More importantly, we don’t threaten your customer base. We only sell PVC-U sash windows, so your customers remain loyal to you and the other products you make.

If you’d like us to explain just how we can help you fulfil sash window orders without the hassle of making them, then tell us about your company here.


You should always use a dedicated sash manufacturer for two important reasons:

  • Focused on just one product, we invest in bespoke solutions and unique system improvements and build long-lasting products.
  • As specialists, we don’t threaten your trade relationship with your installer. Just imagine if your customer started buying sash windows from your competitor, they’d soon consider switching to them completely…

If you’ve never considered buying in finished frames, we come with excellent credentials. We’ll help grow your sash window sales and take away the headache of manufacturing them, allowing you more time to profit from production.

If you’d like us to explain how we can help you fulfil sash window orders, then tell us about your company here and we’ll get in touch. 

Testimonial Michael Hagan

Aztec Windows (Coventry) Ltd, Coventry

“Exceeded our expectations, far superior quality and exemplary service!”

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Call Jack Sellick on 01376 510410 to request our informative Conservation Guide.



Learn why you get better windows because of these

  • BBA logo
  • ISO logo grey
  • Secured by design logo grey
  • BFRC logo grey
  • Energy Trust logo Grey
<h3>Setting standards, safeguarding interests</h3>
<p>Masterframe have been GGF members since the mid 90s. Our MD has served on the GGF main board and chaired the Home Improvement Executive, FENSA and the BFRC. Membership gives you greater protection on a number of levels.</p>
  • DGC logo grey
  • CE logo grey
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