Architectural Glulam Beams

Glulam Beams are 2x4 or 2x6 Douglas Fir dimensional lumber layered and laminated together with durable, moisture-resistant structural adhesives.  By laminating a number of smaller pieces of timber, a single large, strong, structural member is manufactured from smaller pieces.

Our Glulams have an architectural appearance, meaning that the exposed faces have been sanded, and all exposed corners have an eased edge.  It is intended to be installed exposed to the naked eye and takes stain to leave a rich and beautiful color and texture.  

Available Sizes:

Features & Benefits:

-Only Glulam that matches dimensional lumber sizes (3-1/2" and 5-1/2")

     -Ensures a perfect fit when framing 

     -No sheetrock issues or structural connection issues 

-Only Glulam that has an Architectural appearance 

     -Sanded face and micro-eased edge

     -Any small knots and voids are filled 

     -Takes stains exceptionally well

-Matches Engineered Wood depths for seamless compatibility 

-1.9 True E Stress Rating

-Resource-efficient and 100% sustainable 

-Compatible with TJI I-Joists

-Easier to work with than steel - cuts, nails, and handles just like regular timber


Rosboro Glulam Product Brochure

Rosboro Glulam Warranty

Glulam Span Table

Rosboro X-Beam Design Properties

Specification Sheet

Rosboro Glulam Resource Library



Information Request


Open Concept Kitchen 

Removed wall with exposed Glulam

by @crystalanninteriors 


Bissel Tree House - Grand Rapids, MI

C&btr Fir T&G Ceiling and Walls

Glulam Beams and Columns 

The Grove - St. Louis

Glulam Open Concept Stair Case


Dallas Love Field (Deep Depth Glulams):


St. Louis Science Center GROW Exhibit (Curved Glulams):


Compatible with Trus Joist Engineered Wood:


Allowable Holes:


Treated Glulam Beams

Treated glulam beams are pressure treated with a Hi-Clear II, a clear industrial wood preservative. It leaves a light honey color finish that is virtually undetectable to the naked eye.  It is intended for above ground exterior applications and is most common for raised deck beams.  

Available Sizes:

Features & Benefits:

-Allows for a one piece install that meets code

-Treatment does not impact structural integrity of beam, meaning predictable and long-term performance 

-Treated with a honey color stain, leaving a visually appealing and attractive beam

-Helps you eliminate posts and columns, opening up lower level patios and yard space

-Easier to work with than steel - cuts, nails, and handles just like regular timber


Hi-Clear II Finish 


Treated Glulam Product Brochure

Further Information - Treated Glulams



Can I use treated Glulams in an exterior application? 

Yes, as long as your load and span requirements are in line, treated Glulams can be used for most exterior applications.  The most common applications are going to be for decks, large pergolas, awnings, and covered porches.  The only real project where these can't be used is for marine applications, such as a dock.  

Can I cut or drill treated Glulams?

Yes, you can, but any cut or drilled edge should be sealed with a copper naphthenate (often called copper coat) which can be found at most home stores.  This will further protect against any potential rot and decay.  

Can I stain or paint treated Glulams?

While it's not necessary, you can absolutely paint or stain treated Glulams with an oil based product.  

How far can I span between supports?

Use the graph below to figure out your maximum span, but generally speaking, you can easily get to a 16' to 20' span between supports.  This large span opens up living space for below for additional outdoor seating and is a great product for large commercial decks.  


Trying to figure what size beam to use for your deck?  Try this convenient span calculator: 

Special Orders:

  -Available in straight and curved beams

  -Available sizes up to:

        Length = 100'

        Depth = 53"

        Width = 14.25" 

  -Allow up to 6-8 weeks for special orders 

  -Learn more here: Rosboro Custom Beams 


Dallas Love Field (Deep Depth Glulams):


St. Louis Science Center GROW Exhibit (Curved Glulams):



Fiber Source: