FHB Logo Facebook LinkedIn Email Pinterest Twitter Instagram Plus Icon Close Icon Navigation Search Icon Navigation Search Icon Arrow Down Icon Video Guide Icon Article Guide Icon Modal Close Icon Guide Search Icon Skip to content
Subscribe

In every issue you'll find...

  • Expert insights on techniques and principles
  • Unbiased tool reviews
  • Step-by-step details to master the job
  • Field-tested advice and know-how
Subscribe Now!
Subscribe
  • How-To
  • Design
  • Tools & Materials
  • Videos
  • Blogs
  • Forum
  • Magazine
  • Members
  • FHB House
  • Podcast
  • Join
  • Log In
Subscribe
How-To

Glue-Laminated Timbers

Designing and building with engineered beams.

By Stephen Smulski Issue 71

Synopsis: Glue-laminated beams are one kind of engineered structural member taking the place of traditional wood beams cut from a single log. The author discusses how they should be used correctly in residential construction, with details on connecting them to columns and other structural supports. A sidebar compares relative weights and costs of alternatives to glulams, including steel, laminated veneer lumber, and flitch beams.

Until recently, glue-laminated timbers, or glulams, were used chiefly for commercial and institutional structures. Most people know them as the exposed framework of shopping centers and churches. Home builders generally used steel for long spans and sawn timbers for exposed frames.

But times are changing. Open floor plans remain popular with homeowners, as do exposed beams with long, clear spans. Sawn beams that fit the bill are usually milled from large, old-growth trees, which are becoming scarce and expensive. As a result, more builders are turning to engineered-wood products, including glulams. In residential construction, glulams can serve as strong and attractive exposed structural members with long, clear spans. Their uses include arches, headers, girders, ridge beams, joists and rafters. Not surprisingly, glulam sales are expected to double over the next ten years.

Longer, wider, deeper

Glulams are made in a wide range of sizes, stiffnesses and strengths by face-laminating dimension lumber with structural adhesives. The lamination process yields beams that are longer, wider and deeper than sawn beams, so a glulam uses wood more efficiently than a sawn beam. The wood in a glulam is harvested from second- and third-generation trees, taking some of the pressure off old-growth forests.

The laminations in a glulam beam consist of 6-ft. to 20-ft. lengths of 2x dimension lumber (1x for tightly radiused arches), kiln-dried to an average 12% moisture content. The lumber is end-joined with structural finger joints and a waterproof, synthetic-resin adhesive (melamine, phenol, resorcinol, or phenol-resorcinol-formaldehyde). In the U. S., most glulams are made from Southern yellow pine or Douglas fir, although redwood, Alaska yellow cedar and Western red cedar are also used. In theory, there’s no limit to a glulam’s size, but like most building materials, they’re shipped by truck and rail. This limits lengths to 100 ft. or so (oversized trailers are used to ship glulams longer than 60 ft. over the road).

Almost all glulams are horizontally laminated. Adhesive is spread on one wide face of each lamination; the laminations are then placed in a clamping jig. The adhesive cures at room temperature and develops sufficient strength so that clamps can be removed in 6 hours to 24 hours. The glulam is then set aside for a brief conditioning period during which the adhesive develops full strength.

After conditioning, the glulam is surface-planed and crosscut to length as needed. Tapered glulams and arches are machined to their final shape. Edges are eased, and splits, knots and other surface imperfections are plugged and smoothed to meet appearance-grade requirements. Some manufacturers may bore connector holes and apply end sealers, primers, or surface finishes. Some also supply fasteners, hangers and engineering assistance upon request. Before shipping, glulams are wrapped in kraft paper or a housewrap-rype material that keeps the beam dry, yet lets it breathe. The wrapping also prevents surface marring during storage, transport and erection.

For more photos and information on glue-laminated timbers, click the View PDF button below. 

Sign up for eletters today and get the latest how-to from Fine Homebuilding, plus special offers.

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters
×

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters
View PDF

New Feature

Fine Homebuilding Forums

Ask questions, offer advice, and share your work

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Up Next

Video Shorts

Featured Story

5 Steps for Flashing a Deck Ledger

A multilayered approach keeps water out of the house at this critical connection.

Featured Video

How to Install Cable Rail Around Wood-Post Corners

Use these tips to keep cables tight and straight for a professional-looking deck-railing job.

Related Stories

  • Dress Up a Ceiling With Reclaimed Beams
  • Podcast 527: Sloping Decks, Brick-Filled Framing, and Skylights
  • Advantages of a Vented Over-Roof
  • Air-Sealing Exposed Rafter Tails

Discussion Forum

Recent Posts and Replies

  • |
  • |
  • |
  • |
  • |
  • |
View More Create Post

Highlights

Fine Homebuilding All Access
Fine Homebuilding Podcast
Tool Tech
Plus, get an extra 20% off with code GIFT20

"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Video

View All
  • Podcast 535: Members-only Aftershow — Architectural Styles
  • Podcast 530: PRO TALK With Architecture Student Phillip Schladweiler
  • Podcast 524: PRO TALK With Design Department Manager Candice Rania
  • Balancing Design and High-Performance Construction
View All

Architecture and Design

View All Architecture and Design Articles
  • front of house
    Combining Design Aesthetics for an Island Home
  • Photo of a large open window opening onto an urban neighborhood
    Editorial Note: Living Smaller
  • front of house
    Modern and Geometric Home in New England
  • affordable housing design
    Innovative Design in Affordable Housing
View All Architecture and Design Articles

BOOKS, DVDs, & MERCH

Shop the Store
  • Pretty Good House
    Buy Now
  • Code Check Building 4th Edition
    Buy Now
  • 2023 Tool Guide
    Buy Now
Shop the Store

Fine Homebuilding Magazine

  • Issue 313 - Feb/March 2023
    • Practical System for a Seismic Retrofit
    • Fine Homebuilding Issue #313 Online Highlights
    • Practical System for a Seismic Retrofit
  • Issue 312 - Dec 2022/Jan 2023
    • Tool Test: Cordless Tablesaws
    • Gray-Water System for a Sustainable Home
    • Insulate a Cape Roof to Avoid Ice Dams
  • Issue 311 - November 2022
    • 7 Steps to a Perfect Exterior Paint Job
    • Options for Smarter Home-Energy Tracking
    • The Fine Homebuilding Interview: James Metoyer
  • Issue 310 - October 2022
    • Choosing a Tile-Leveling System
    • Choosing Between HRVs and ERVs
    • Custom Built-in Cabinets Made Easy
  • Issue 309 - Aug/Sept 2022
    • 10 Steps to Install Crown Molding on Cabinets
    • How to Get Sturdy Walls Without OSB
    • Choosing the Right Construction Tape for the Job

Fine Homebuilding

Follow

  • twitter
  • facebook
  • instagram
  • pinterest

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Membership & Magazine

  • Online Archive
  • Start Free Trial
  • Magazine Subscription
  • Magazine Renewal
  • Gift a Subscription
  • Customer Support
  • Privacy Preferences

Taunton Network

  • Green Building Advisor
  • Fine Woodworking
  • Fine Gardening
  • Threads
  • About
  • Contact
  • Advertise
  • Careers
  • Copyright
  • Terms of Use
  • Site Map
  • Do not sell or share my information
  • Privacy Policy
  • Accessibility
  • California Privacy Rights

© 2023 The Taunton Press, Inc. All rights reserved.

X
X
This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

Main Menu

  • How-To
  • Design
  • Tools & Materials
  • Video
  • Blogs
  • Forum
  • Reader Projects
  • Magazine
  • Members
  • FHB House

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Account

  • Log In
  • Join

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Popular Topics

  • Kitchens
  • Business
  • Bedrooms
  • Roofs
  • Architecture and Design
  • Green Building
  • Decks
  • Framing
  • Safety
  • Remodeling
  • Bathrooms
  • Windows
  • Tilework
  • Ceilings
  • HVAC

Magazine

  • Current Issue
  • Past Issues
  • Magazine Index
  • Subscribe
  • Online Archive
  • Author Guidelines

All Access

  • Member Home
  • Start Free Trial
  • Gift Membership

Shop the Store

  • Books
  • DVDs
  • Taunton Workshops

More

  • FHB Ambassadors
  • Reader Projects
  • Podcast
  • Customer Support

Account

  • Log In
  • Join

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Follow

  • twitter
  • facebook
  • instagram
  • pinterest

Join All Access

Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.

Start Your Free Trial

Subscribe

FHB Magazine

Start your subscription today and save up to 70%

Subscribe

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

Start your FREE trial

Already a member? Log in