Heavy Duty Canvas Stretcher Bars

The larger the canvas, the more important it is to have it supported by a professionally made stretcher. Large canvases are prone to twisting and sagging and only by using a fully keyable, heavy-duty stretcher is it possible to maintain rigidity and proper canvas tension over the life of the painting.

As many artists have discovered, it is very difficult to make a straight stretcher bar longer than 8 feet out of solid wood. The longer the bars, the more likely it is that the wood will bow or twist and make the stretcher frame unusable. We have found that the only reliable way to make long stretcher bars strong and straight is to laminate two or more lengths of wood together. Every heavy-duty bar we use in our large frames has been glued and set in clamped jigs to produce very strong, straight and stable stretcher components.

Upper Canada Stretchers  specializes in making very large stretcher bars and we have extensive experience with frame dimensions over 30 feet across! Our  extra-strong, laminated stretcher bar profiles and sectional, easy-to-assemble splice joints that make it possible to create fully keyable stretchers of any size.


  • Laminated & finger jointed clear white pine for superior strength and stability
  • Double and triple tongue & groove friction joints for stronger corners
  • Heavy-duty cross braces for maximum support and clearance
  • Flush-bolted sectional designs for ease of shipping and assembly
  • Fully keyed bars and braces for fast and precise tensioning of canvas
  • Folding designs for easy transportation
  • Easy assembly complete with instructions and tools provided



Read More About our Extra Large Stretcher Frames


We offer the following heavy-duty stretcher bar profiles to meet a wide range of large canvas support situations. Note that different weights and types of canvases require more or less support for proper tensioning. It’s important for you to communicate to us any details about the canvas to be stretched so that we can recommend the most appropriate frame.

– Ideal for small to large canvases up to around 72″

– Most commonly used for canvases 72″ to 120″

– Most commonly used for canvases 72″ to 144″ or in situations requiring more space between canvas and frame

– Commonly used for canvases over 120″


– Commonly used for canvases over 140″


Get a Quote for Your Extra Large Stretcher Frame

Below are some examples of the large stretcher frames that Upper Canada Stretchers has created for various clients around the world:

15′ x 36′ heavy-duty stretcher frame made for the Royal Ontario Museum, Toronto, Canada

Assembling a triptych in our shop (three canvases connected to become one large one)

Three canvases 102″ x 74″ connected to form a triptych – primed with acrylic gesso on #10 canvas on Heavy-Duty Professional stretcher


13′ x 8′ frame to be hung in the Mary Chapel of St. Anthony’s Church in The Woodlands, Texas

Our on-site stretching services  were  utilized to help stretch this completed 7′ x 20′ painting in Toronto, Ontario


Toronto artist, Lynn Kelly, prepares to stretch raw linen canvas on a 72″ x 120″ Heavy-Duty Standard frame (above) and completing the job (below).


Test fitting a large Heavy-Duty Professional frame in our shop


There are many factors that we consider in designing proper support for large canvases. Please  fill out our quote form or phone us at 1.800.561.4944 – we are happy to help guide you through your project.