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Ordering or obtaining a quotation could not be easier.

1.  Either call us on 01443 226987 to discuss your requirements or
2.  Download and print one of our order/quote forms and fax, email, or post the form to us.
Download PDF for Bi-Fold Doors
Download PDF for Vertical Sliders
Download PDF for Casement Windows and/or Doors



GRM windows was founded by Gareth Gambling In 1975. After installing high quality windows, selling to trade was the next step. His philosophy has always been to supply high quality windows at a competitive price.
To achieve this, his belief has always been to keep the service personal, whilst investing in top line machinery to produce the windows.
Richard Gambling Joined GRM in 1994 with a view to taking GRM forwards for the next 30 years.

Our factory has some of the most sophisticated manufacturing machine available to the industry. This enables GRM to produce windows with fast turn-around, very accurately and efficiently.

 Rehau windows doors and conservatories  download brochure

 Rehau heritage doors and windows download brochure

 Rehau creative doors and windows download brochure

 Rehau multi-fold doors download brochure





"GRM Windows build a wide range of windows, doors and conservatories from leading manufacturers including Rehau, Door Stop, Synseal and Hurst Plastics" 

 Panel Doors The Definitive range of door panels combines the very latest PVC-U sheet technology with bespoke glass designs.  Coupled with our extensive manufacturing experience, the result is a stunning portfolio of unique door panel designs for the discerning home owner...read more
 Composite Doors Our composite doors can be as individual as you like. You can choose from 7 door leaf colours, hinge edges, glazing and hardware to suit your requirements and aesthetics...read more
 Bi-Folding Doors As a popular alternative to more traditional PVC French doors and PVC sliding patio doors, bi-fold doors can create an open plan feel  for any type of building.  The multi-facet panes of the bi-fold door fold back to allow a wide opening...read more
 Patio & French Doors We offer a wide range of possibilities when a large opening is required to link the inside of a building to the outside.  Our patio doors provide great aesthetics, durability and are energy efficient. A patio door will meet all your requirements, while offering an extensive variety of styles and functionalities...read more
 Conservatories Country cottage, or period property, barn conversion or bungalow, large or small space there are a huge variety of uPVC Conservatory styles to suite every home, taste and pocket.  A uPVC Conservatory will provide you with a room to relax, dine or play combined with the appeal of being outdoors...read more
 Sliding Windows Designed to replicate traditional timber box sash windows, uPVC sliding sash windows manufactured from the REHAU Heritage system provide you with a traditional looking sash window combined with the numerous benefits of uPVC...read more
 Casement Windows Casement windows are the most popular style of replacement window in the UK – an extremely versatile window that will suit most homes wherever you live...read more


AV2 Automatic Multi Point Locking System
Upvc doors historically, have needed two operations to lock. Lift handle, turn key. This means that unless you ’lock’ your front door, the house would be insecure.  Now GRM are proud to offer the  AV2 Automatic Door Lock - an automatic system that requires no wiring or power supply.
 Do the elderly and infirm have difficulites lifting handle levers to throw multi-point locks?
 Do some tenants forget to actually throw the hook/deadbolt, thus compromising security?
 I am unable to lock the door. Does this sound familiar?
 Would a slam shut multipoint locking system give great peace of mind?
If you have answered YES to these questions then the answer is the Winkhaus Cobra AV2 AUTOMATIC multipoint lock click here 



"Traditional and contemporary designs, incorporating the beauty of wood, with the reliability of uPVC"

Standard timber windows can be expensive and high maintenance, which is why we are developing a range of timer style replica windows.  Both practical and beautiful, we combine the traditional skills of joinery and craftsmanship, with modern technology, to create a window that has improved energy efficiencies and enhanced security features.
Maintenance free core that is cleverly covered with white wood-grained foil that looks just like a timber frame painted with micro-porous paint
Mullions and transoms are mechanically jointed and shadow grooved by hand just as with timber frames
Specified with old fashioned wrought iron handles and lots of hand finished detailing to a clients personal taste
Old fashioned opening stays, Monkey tail handles and float bar French door mechanisms enable clients to make their windows and doors identical to wood






GRM Windows manufacture and supply some of the most well established window and door installers in the South Wales. To find one close to you, please contact us and we will provide a list of your nearest approved installers. 


or contact us on 01443 226987
to discuss options available



GRM Windows Ltd
Old Joinery Yard,
Station Terrace,
Vale of Glamorgan
CF72 9DZ
(t) 01443 226987
(f) 01443 225299
Company Registration: 3241117
VAT Number: 682302057







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