Best Practices Guide Exterior Adhesives & Glues for buildings

Exterior building construction adhesives and glues
Type II yellow glue for outdoor use
Polyurethane glues for outdoor use
Epoxy glues for outdoor construction use
Questions & Answers about construction glues & adhesives
References

Click to Show or Hide Related Topics

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

This article series discusses best practices construction details for building exteriors, including water and air barriers, building flashing products & installation, wood siding material choices & installation, vinyl siding, stucco exteriors, building trim, exterior caulks and sealants, exterior building adhesives, and choices and application of exterior finishes on buildings: paints, stains.

Exterior Building Adhesives & Glues: Product Choices, Installation Details

See CAULK GUN TYPES, CHOICES, also see CAULKS & SEALANTS, EXTERIOR. Some caulks and sealants also act as glues or adhesives. Adapted/paraphrased with permission from Best Practices Guide to Residential Construction. Steven Bliss.

No exterior millwork should rely entirely on adhesives, since no glue is 100% waterproof, and any adhesive can fail with enough moisture cycling and movement in the wood. It is always wise to back up an exterior glue joint with mechanical fasteners, design the woodwork to shed water, and protect it with a good paint job. Still, there are several good options for gluing exterior work that should last indefinitely if well maintained (see Table 1-14) [click to enlarge].

Exterior adhesives and glues (C) Wiley and Sons, S Bliss

There are several factors to consider in selecting a glue. For exterior woodwork, the biggest concerns are typically water resistance, strength, and cleanup. Working temperatures, clamping time, and gap filling abilities may also be important, depending on the specific job and conditions.

A glue’s water resistance is classified as Type I or Type II. A Type I designation indicates that the glue bond can survive repeated submerging in boiling water. Type 1 glues are used for laminating structural timbers such as glulams. The most common Type 1 glue, resorcinol, has strict temperature and clamping requirements and is rarely used on residential job sites. Type II glues must maintain their bond after being soaked for four hours and then dried three successive times. These are suitable for all but the most punishing residential applications.

Guide to Type II Yellow Glue on Building Exteriors

Polyvinyl acetate (PVA) is the most common glue on residential job sites due to its low price, long shelf life, easy cleanup, and overall ease of use. The Type II version provides good water resistance and provides a very strong bond, and it is only slightly more expensive than the regular yellow glue.

In our photo (left) the yellow Titebond™ glue (at left in the photo) is suitable for the applications discussed here. While Elmers™ also makes a yellow Type II glue, do not use the white "school glue" shown in the center of our photograph for construction purposes. White school glue lacks water resistance and strength and won't work outdoors.

Similar to the older style white glue, yellow glue is formulated with a higher solids content to make it less runny and with other additives to make it set up quicker. Clamp time is about one hour. Any squeeze-out is simple to remove with a damp rag. Once the glue dries, however, it will resist paint and stain and needs to be scraped or sanded off.

In general, yellow glue should not be applied in temperatures below 50°F or allowed to freeze before it cures. In freezing weather, store the glue indoors, since a couple of freeze-thaw cycles may ruin the glue. For exterior work subjected to moderate weather exposure, Type II yellow glue is a good option.

Guide to Polyurethane Glues and Adhesives on Building Exteriors

One-part polyurethane glues have grown in popularity over the past few years due to their excellent strength and increased water resistance compared to yellow glue. Since polyurethane requires moisture to cure, it will bond to wood that has up to 25% moisture content.

For wood that has less than 10% moisture content or appears dry, you should moisten one of the two surfaces being joined with a sprayer or damp cloth and apply a thin coating of glue to the other. Polyurethane bonds well to wood, stone, most metals (not stainless steel), and ceramics, as long as at least one of the surfaces being glued is porous.

Polyurethane foams up as it cures, expanding to three to four times its original size and filling any small gaps in the joint. But unlike epoxy, the filled gaps have no strength. Clamping time is one to four hours, depending on the specific formulation. For maximum strength, clamp for 24 hours.

Because of its tenacious grip, you should protect any materials or finished surfaces from drips and protect your hands with latex gloves, as the glue cannot be removed except by abrasive cleansers.

If wet glue drips onto a finished surface, wipe with a dry cloth, since anything wet will activate curing. After the glue has dried, scrape away the squeeze-out with a sharp chisel and sand any residue. The glue dries to a brownish tan, which can be painted.

OPINION-DJF: we really enjoy almost everything about Gorilla Glue (photo above), and have used it very extensively in both repair (it will expand and secure a wobbly chair leg) and in construction indoors and out. Our favorite indoor project using this glue was building site-built built-up custom curved trim. Our photos (below) show the an in-process stage of constructing custom wood trim in a home as well as the finished result after sanding and finishing.

Polyurethane glue project for curved custom trim (C) Daniel Friedman

We ripped and planed a mix of Brazilian cherry and white oak into narrow strips that were bent to shape, glued, and clamped in place. Critical was to use enough wedges and later clamps to be sure that our wood strips remained closely aligned with no open gaps during drying. We cut away the flue overflow after it dried, by hand, using a sharp chisel. A final sanding with an orbit sander and a router to round the edge of our curved trim/stair was all that it took to produce a beautiful end product.

What's not to enjoy: working wearing protective plastic gloves proved impossible - as soon as the gloves got sticky with glue it was impossible to pick up anything. Working bare-handed means you will have glue on your hands for several days. Washing the dishes in the kitchen sink every day will speed wearing off of this ooky mess.

Continuing from from Best Practices Guide to Residential Construction:

Hot Melt Glue Uses in Construction

Where clamping is not practical, another option is hot melt polyurethane. Hot-melt polyurethanes have been used in industrial settings for many years, but they have only recently been introduced for job-site use.

Unlike its moisture-cured cousin, hot-melt polyurethane does not foam up and needs no clamping.

It sets in about 30 seconds and provides the same level of water resistance as regular polyurethane but less than half the strength.

Still, this is more than enough for many applications. Remove any squeeze-out with a putty knife or scraper as soon as it firms up, as it is difficult to sand clean.

Using Epoxy Glues and Adhesives on Building Exteriors

Long the adhesive of choice for boat builders, epoxy has high adhesive strength and rigidity, low shrinkage, and good resistance to water and chemicals. It bonds well to wood, concrete, foam insulation, and other porous substrates—and to nonporous surfaces as long as they are lightly roughed up.

epoxy is comparable in strength and water resistance to polyurethanes, requires minimal clamping, and can fill gaps with little loss of strength, making it an ideal choice for less-than-perfect carpentry joints.

In our photo (left) an example of Loctite™ Epoxy is on the right.

As a two-part system—with various hardeners to choose from and additives such as fillers to improve gap filling—epoxy is also the most complicated and costly approach. Once the resin and hardener are mixed, the working time ranges from about 10 minutes to an hour, depending on the ambient temperature and whether a slow or fast hardener is used. Heat speeds up the curing, so a slow hardener is recommended in hot weather, a fast hardener in cold weather. It is important to mix the correct proportions and mix thoroughly or un reacted resin or hardener may remain in the cured epoxy.

For best results, use a disposable brush to coat both sides of the joint with liquid epoxy. After coating the joint, add fillers to the mix if required. Fillers change the viscosity of the mix and enable it to bridge gaps with minimal loss of strength (you can bridge small gaps up to about 1/16-inch without fillers).

A small amount of filler helps keep the mix from running. Once the fillers have been added, apply the thickened epoxy to one side of the joint and clamp just enough to squeeze out a little epoxy. A common mistake with epoxy is clamping too tightly. This will create a weak, “glue-starved” joint. Cleanup of the wet epoxy requires solvents such as acetone or lacquer thinner. Workers should use rubber gloves to protect their skin.

Any kind of clamping that holds the joint still is suitable, including staples, nails, or wood screws. Scrape off any squeeze-out with a putty knife or dry rag. Once the epoxy has cured to a solid state that cannot be dented with a fingernail, it has reached 90% of its final strength. Then the clamps can be removed and any excess sanded off. The epoxy continues to gain strength for several days and is paintable.

-- Adapted with permission from Best Practices Guide to Residential Construction.

Resources for Building Exterior Products

Construction Sealant (Caulks) Suppliers & Products

Chemrex www.chemrex.com

Polyurethanes and other high-performance sealants

DAP www.dap.com

Acrylic latex caulks

Dow Corning Sealants www.dowcorningsealants.com

Silicone sealants

GE Silicones www.gesilicones.com Silicone sealant

Geocel Corp www.geocelusa.com Acrylic latex, tripolymer, copolymer, Kraton, and clear sealants

Macklanburg-Duncan www.mdteam.com Acrylic latex sealants

OSI Sealants Inc www.osisealants.com Polyseamseal PVA-based caulk. Pro Series includes latex, polyurethane, and Kraton sealants.

www.phenoseal.com Phenoseal vinyl adhesive caulk

Red Devil www.reddevil.com Acrylic, silicone, and butyl sealants

Sashco Sealants www.sashco.com Big Stretch and Mor-Flexx water-based sealants, Lexel Kraton sealant

Sika Corp www.sikaconstruction.com Complete line of Sikaflex polyurethane-based sealants, butyl sealant

Tremco Inc. www.tremcosealants.com High-performance, architectural-grade sealants,

UGL www.ugl.com Acrylic latex caulks

White Lightning www.wlcaulk.com Tripolymer, butyl, polyurethane, silicone, elastomeric, and other high-performance sealants

Exterior Adhesives

Abatron EpoxyWood Repair/Restoration 5501 - 95th Avenue, Kenosha, WI 53144 USA Tel: (262) 653-2000 Fax: (262) 653-2019, For orders: (800) 445-1754 Abatron provides a wide range of wood & building restoration epoxy products including a low-viscosity system that penetrates and solidifies rotted wood and a thicker wood repair putty type epoxy.
Epoxy, BestBond polyurethane glue

Ambel www.excelglue.com Excel polyurethane glue

Elmer’s Products www.elmers.com Yellow glues, ProBond polyurethane glue

Custom-Pak Adhesives www.custompak.com Resorcinol and yellow glues

DAP Inc. www.dap.com Weldwood contact cement, resorcinol, and construction adhesives Resources 49

Franklin International www.titebond.com Titebond yellow glue, Liquid Hide Glue, and construction adhesives

Gloucester Co. Inc. www.phenoseal.com Phenoseal adhesive caulk

Gougeon Brothers www.westsystem.com West System epoxy

Gorilla Group www.gorillaglue.com Gorilla polyurethane glue

MACCO Adhesives www.liquidnails.com Liquid Nails construction adhesive

SI Sealants www.osisealants.com PL400 construction adhesive

System Three Resins www.systemthree.com Quick Cure epoxy

-- Adapted with permission from Best Practices Guide to Residential Construction.

Frequently Asked Questions (FAQs)

...

Ask a Question or Search InspectApedia

Questions & answers or comments about construction glues & adhesives.

Ask a Question or Enter Search Terms in the InspectApedia search box just below.

Technical Reviewers & References

Related Topics, found near the top of this page suggest articles closely related to this one.

Steve Bliss's Building Advisor at buildingadvisor.com helps homeowners & contractors plan & complete successful building & remodeling projects: buying land, site work, building design, cost estimating, materials & components, & project management through complete construction. Email: info@buildingadvisor.com
Steven Bliss served as editorial director and co-publisher of The Journal of Light Construction for 16 years and previously as building technology editor for Progressive Builder and Solar Age magazines. He worked in the building trades as a carpenter and design/build contractor for more than ten years and holds a masters degree from the Harvard Graduate School of Education. Excerpts from his recent book, Best Practices Guide to Residential Construction, Wiley (November 18, 2005) ISBN-10: 0471648361, ISBN-13: 978-0471648369, appear throughout this website, with permission and courtesy of Wiley & Sons. Best Practices Guide is available from the publisher, J. Wiley & Sons, and also at Amazon.com
Best Practices Guide to Residential Construction, by Steven Bliss. John Wiley & Sons, 2006. ISBN-10: 0471648361, ISBN-13: 978-0471648369, Hardcover: 320 pages, available from Amazon.com and also Wiley.com. See our book review of this publication.
Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. Mr. Cramer serves on the ASHI Home Inspection Standards. Contact Mark Cramer at: 727-595-4211 mark@BestTampaInspector.com
John Cranor is an ASHI member and a home inspector (The House Whisperer) is located in Glen Allen, VA 23060. He is also a contributor to InspectApedia.com in several technical areas such as plumbing and appliances (dryer vents). Contact Mr. Cranor at 804-747-7747 or by Email: johncranor@verizon.net
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides:
- Commercial Building Inspection Courses - protocol ASTM Standard E 2018-08 for Property Condition Assessments
- Home Inspection Education Courses including home study & live classes at eleven colleges & universities.
- Home Inspection Education Home Study Courses - ASHI@Home Training 10-course program.
  Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference Book, a reference & inspection report product for building owners & inspectors.
  Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference eBook, an electronic version for PCs, the iPad, iPhone, & Android smart phones.
  Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter inspectaehrb in the order payment page "Promo/Redemption" space.
- The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors.
  Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
- The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones.
Paul Galow - technical consultant on networking, LAN design, applications support. Galow Consulting Services, 914-204-1749, email: paulgalow@galowconsulting.com
John Rudy, Advantage Home Inspections, Flemington N.J. 08822 home inspector, 908-806- 6364, Home, Radon & Termite Inspections, Central & Parts of North New Jersey, email: jonadvantage1@yahoo.com
Malco® Products siding tools are available from that company, including the SideSwiper II SRT2 discussed at Malco's website. Websearch 09/07/2010 http://malcoproducts.com/product/roofing-siding-gutter/siding-vinyl/siding-tools-vinyl/sideswiper-ii. Malco also produces other vinyl siding repair tools such as aprons, awls, hole punches, saw blades, and tools for for fiber cement products including power-assisted cutters
Parmetol, a wood preservativerecommended by the manufacturer was used as a fungicidal additive to paint on the Blue Poplar wood sculpture in Amsterdam, by artist Mari Shields [ - art conservation consult DJF-artist MS 2010]
"Weather-Resistive Barriers [copy on file as /interiors/Weather_Resistant_Barriers_DOE.pdf ] - ", how to select and install housewrap and other types of weather resistive barriers, U.S. DOE

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.

The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.

Building inspection education & report writing systems from Carson, Dunlop & Associates Ltd

Decks and Porches, the JLC Guide to, Best Practices for Outdoor Spaces, Steve Bliss (Editor), The Journal of Light Construction, Williston VT, 2010 ISBN 10: 1-928580-42-4, ISBN 13: 978-1-928580-42-3, available from Amazon.com
The Journal of Light Construction has generously given reprint permission to InspectAPedia.com for this article. All rights and contents are ©Journal of Light Construction and may not be reproduced in any form.
...


	InspectAPedia^®	InspectAPedia
	Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair	Ask a Question or Search InspectAPedia

Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia