Our “Slim-Jim” Window ~ Ask for it by name!

The ultimate Slimline uPVC Window

Exclusive to Thermaglaze

Less frame, more light

The elegant, slim framework of our exclusive Slim Jim uPVC window system allows more light to flood into your home.

The ultra slim sightlines provide a much greater glass area than current standard casement windows and are perfectly suited to both modern and traditional houses.

Beautifully refined ultra slim sightlines

Our exclusive Slim Jim window system is defined by its stunning ultra slim sightlines. Slender and elegant, they allow for a greater glass area and give a more refined look to a property – whether it is of traditional or contemporary design.

More glass means much more light

The increased glass area of our Slim Jim windows allows your room to be flooded with significantly more natural light, creating a warm and airy home environment for you and your family.

You’ll be amazed by the difference that the Silhouette’s slimmer frames can make to the ambience of your home.

Available to view at our showroom DOWNLOAD BROCHURE

The Thermaglaze process

We pride ourselves on offering the very best experience for our customers throughout every stage of the process.
Known fondly as the “Thermaglaze experience".

From quote to installation, we make it easy for you!

"Have used Thermaglaze for many years. Always professional, helpful and very courteous. Delighted with completed work."

Mr J Watson








What our customers say

Don’t just take our word for it. Hear what our customers have to say!

You were able to offer us a slimline frame which matched the original windows and look more stylish than the thicker uPVC frames.

Mr & Mrs D.S

Slimline uPVC Window, Wincanton

No charge for sales on-site visit (others need commitment before site visit).


Bi Fold Door, Slimline Windows, Taunton