Visit our Composite Doors page and design your dream door with our easy to use online door designer. Submit your design to us for a free, no obligation composite door quotation and we will automatically apply a £100 discount. No catches, no obligation and no time to lose!

We offer premium quality, locally manufactured, high security A-Rated uPVC windows to suit all property styles. All of our windows are Energy Rated, attractive and all installations are covered by a 10 year guarantee.

Whether you require Patio, French, Bifold, uPVC or Composite doors, we have the product for you. You can even design your own GRP Composite Door on our website and try out different styles, colours and options.

If you are suffering from misted units, cracked glass or condensation you may not require a new window. We are happy to provide replacement glass units at a fraction of the cost of replacing your windows.

The best windows Merthyr Tydfil has to offer!

We are a FENSA registered double glazing company with over 30 years of experience and an extensive knowledge of installing windows, doors and conservatories. We are happy to help you design and plan the layout, colour and style of your new windows and doors and are happy to advise you on energy ratings. 


Here at Principality Windows we aim to make all your home improvement projects run as smooth as possible, from the initial meeting through design and final installation. We are able to cherry pick the best quality products that are available within the industry, which ensures our clients can rest assured that they are having the best products at competitive prices.


We provide a first class professional service to the people of South Wales and surrounding areas. If you would like to enquire about home improvements to your home please visit our Contact page and send us a message. Alternatively please call the Office on 01685 884 960, Kevin on 07875 051 169, to arrange a free, no obligation quotation.


A chat costs nothing, and could save you being overcharged by larger companies who charge you for their commissions and advertising!

double glazing south wales

Merthyr tydfil windows at their very best!

Merthyr Tydfil windows at their finest. Whether you are looking for uPVC windows in Caerphilly, uPVC windows in Aberdare, uPVC windows in Bridgend, uPVC windows in Cardiff, uPVC windows in Newport, uPVC windows in Swansea, uPVC windows in Brecon or new windows anywhere in South Wales, Principality Windows are here to help. Our South Wales window centre is small enough to care and large enough to deliver.

Save 10% off all orders of 6 or more windows. Discount will be applied to your entire order whilst this offer runs!

Offer ends January 31st 2018

Best priced Composite Doors in Aberdare

We are official and approved Suppliers and Installers of Truedor GRP Composite Doors. Truedor doors are endorsed by Channel 4's "Restoration Man" George Clarke.

What is a composite door?

Composite Doors are extremely robust, secure and attractive entrance doors with the appearance of wooden doors. They do not posses the same negative qualities of wooden doors, in that they will not warp, rust, peel or fade, and they do not require painting. Nothing compares to the security that a GRP Composite Door can offer, and with Multi-Point Locking and hinge side Triple Dog Bolts fitted to every Truedor Composite Door we install, your family and possessions are safe and secure at all times. Our Truedor Composite Doors are all fitted by our Official Truedor Approved Installers and, for your peace of mind, are provided with a 10 year Installation Guarantee as well as a 10 Year Manufacturers Guarantee. Design your door online and we will email you a no obligation quotation within 24 hours.

truedor installers

10 Year Insurance Backed Guarantees

home pro insurance backed guarantee

The HomePro Group has specialised in the home improvement industry for over thirty years and has become one of the UK's leading providers of deposit protection and insurance backed guarantee products in the home improvement sector.

All supply and fit jobs that we perform will be covered by a 10 Year Insurance Backed Guarantee, including deposit protection.

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Copyright © 2018 by Principality Windows Ltd

Registered in England and Wales. Company Registration No 9989841. VAT Registration No 252264716


01685 884 960

07875 051 169












South Wales Valleys

Llantwit Major


double glazing installers
FENSA Aberdare
rehau authorised partners
home pro insurance backed guarantee