You know how we learn things. It’s never the easy way, is it?
Planning ahead to incorporate ThermalBuck into the building envelope is the key to a good installation. We’ve listed the main points you need to take into consideration in order to prevent issues and potential failures. It’s helpful to watch the installation videos, too. Spending a little time up front planning your installation will help minimize waste of both material and time once you get rolling.
This residential grade sealant provides a durable, 100% waterproof & weatherproof seal around windows & doors. Working time = 30 minutes. Tack free in 2 hours. Complete cure in 24 hours. Packaged in traditional sealant tubes, it requires a standard sealant gun for use.
For more information, please visit dapspecline.com. *For ThermalBuck installations in CANADA, use DAP 3.0 Window, Door, Trim & Siding High Performance Sealant.
DAP Dynaflex 800 can be purchased directly from BRINC Building Products. Inc with ThermalBuck. Call #888.814.2825 for pricing.
FAQ’s – Frequently Asked Questions
Choosing the Right Depth
Choosing the Right Depth ThermalBuck
ThermalBuck is available in 7 different depths. The one you choose should match the thickness of the exterior insulation, and/or rainscreen.
If they don’t match up exactly and you’re between two sizes of ThermalBuck, in most cases we recommend choosing the smaller of the two sizes.
Once you add the sealant behind ThermalBuck, the thickness of the nail flange, and a layer of flashing tape, everything should line up within 1/8″ – 1/16″ for easy attachment of cladding.
The layers add up – sealant + ThermalBuck + nail flange + tape
1.0″ ThermalBuck with 1.0″ Neopor graphite exterior insulation
ThermalBuck ships to the job site in 8′ lengths, and is cut to fit on site.
In order to minimize waste, you can use split pieces on some of the jambs, but we do recommend using whole pieces at the head & sill.
Use this formula to best estimate how many linear feet of ThermalBuck you’ll need for your installation.
Total RO linear feet + 2.0′ per RO + 10% = ThermalBuck*
Use our online ThermalBuck calculator to estimate your order total. Don’t forget to add in the measurements for your doors, too.
*Assumes the use of split pieces on some of the the jambs, whole pieces on head and sill.
Preparing the Rough Opening
Preparing the Rough Opening
You’ll need to oversize the rough opening on all 4 sides to accommodate the 1/2″ tongue of ThermalBuck. The unique “L” shape is an important design element that helps handle the compressive and shear loads, and support the weight of the window.
Review the rough opening preparation from the window manufacturer, then add an additional 1″ overall to their rough opening recommendation to accommodate ThermalBuck.
Interior shot with window installed. Finish sill with on-site scrap drywall or plywood – cover with trim.
Window Width
Rough Opening Width per Window Manufacturer
NEW Rough Opening Width with ThermalBuck Installation
35.5″
36″
37″
Window Height
Rough Opening Height per Window Manufacturer
NEW Rough Opening Height with ThermalBuck Installation
We recommend using split pieces of ThermalBuck on some of the jambs to use up the smaller pieces you’ll have left over.
Miter cut at the correct angle to shed water away from the rough opening. Use plenty of recommended sealant at the joint for a good air & water seal. Insert roofing nails close to each seam.
Use split pieces of ThermalBuck on the jambs if needed to minimize waste.
Whole pieces are preferred at the head and sill for good drainage. If it is necessary to seam pieces of ThermalBuck at the head or sill because the opening is larger than 8′ wide, use a butt joint to shed water. Apply sealant, and wrap flashing tape around the seam (butt joint only) before installing the window.
For small windows, it’s easier to do the jambs last.
Nail close to each seam.
Cover mitered seams with sealant.
Recommended Sealants
Recommended Sealants
The right sealant is essential in achieving a good air & water seal with ThermalBuck. We recommend installing ThermalBuck with sealants specifically designed for window flashing and fenestration materials. They’re durable, flexible, UV resistant, and adhere without priming.
You’ll use three 3/8″ beads on every piece of ThermalBuck, on the mitered ends, and around the perimeter where it meets the sheathing. Also, on the nail flange of the window. In the interior, sealant is needed at the transition of ThermalBuck to the window, and where it meets the framing.
To estimate how much sealant you’ll need to install ThermalBuck (including the window and interior seal), we recommend approximately 1 oz of sealant per linear foot of ThermalBuck.
Photo sourced from basf.us Master Builder Solutions NP1 brochure
This is a single-component, non-priming, elastomeric polyurethane sealant. Cure times varies with temperature and humidity. Skin cure time 24 hours, full cure up to 1 week. Available in bulk packaging, sausage tubes, or traditional sealant tubes.
Adheres without priming to most common building materials, including concrete & masonry
Excellent bonding & flexibility: Joint movement capability ± 35% (ASTM C 719
This residential grade sealant provides a durable, 100% waterproof & weatherproof seal around windows & doors. Working time = 30 minutes. Tack free in 2 hours. Complete cure in 24 hours. Packaged in traditional sealant tubes, it requires a standard sealant gun for use.
Adheres to most common building materials
Excellent flexibility
Adheres to wet surfaces
Extreme temperature use – 0°F to 120°F
ASTM C719 +/-25% joint movement capability
Low VOC
Meets AAMA 803 & 808, ASTM C920
For more information, please visit dapspecline.com. *For ThermalBuck installations in CANADA, use DAP 3.0 Window, Door, Trim & Siding High Performance Sealant.
DAP Dynaflex 800 can be purchased directly from BRINC Building Products. Inc with ThermalBuck. Call #888.814.2825 for pricing.
DAP DRAFTSTOP 812 Window & Door Foam
This is a low pressure, single component polyurethane foam designed to fill gaps between windows & doors, and rough openings. It can be used on the interior, between ThermalBuck and the window framing.
DAP Draftstop 812 can be also be purchased directly from BRINC Building Products. Inc with ThermalBuck. Call 888.814.2825 for pricing.
DowSil 758 Silicone Weather Barrier
This is a commercial grade, neutral one part RTV (room temperature vulcanization), neutral-cure silicone sealant. It has excellent adhesion to a wide range of building materials, including polymeric surfaces, and offers primerless adhesion. DowSil 758 can be used over a wide temperature range, and begins curing immediately by reaction to moisture in the air. Working time = 15 minutes. Complete cure time 24 hours. Packaged in sausage sealant tubes to minimize waste, it requires a sausage sealant gun for use.
Long-term silicone durability
Excellent durability, remains flexible
Sealant Waterproofing Restoration Institute Approved (SWRI)
Henry AIR BLOC LF® liquid applied flashing is a fast curing, single-component elastomeric flashing using a silyl-terminated polyether (STPE). This sealant can be used both for ThermalBuck attachment, and as flashing once the window goes in.
This moisture-cure sealant provides a heavy-duty, rubber-like membrane with excellent weather and water resistance. Available in 20 oz. sausage tubes to minimize packaging waste. Achieves full cure in 24 hours.
Seamless and self-gasketing
Mold resistant
Bonds and cures in wet weather, surfaces must by dry
Henry Fortifiber Moistop® Sealant & Liquid Flashing
Photo sourced from smallplanetsupply.com
This hybrid product can be used as both a sealant and a flashing agent. Combining silicone and polyurethane technologies, Moistop® offers the elasticity, moisture resistance, and long-term durability of silicone, with the excellent bonding ability of a polyurethane. Full cure time 24 hours.
Moistop® can also be used as a liquid flashing, and exceeds AAMA 714 standards. It is available in 20 oz. sausage tubes to minimize packaging waste.
AirDam waterproofing sealant is a single component, silyl-terminated polymer (STP). It combines the best properties of both silicone and polyurethane, to create a long-lasting, weather-tight seal around windows & doors. AirDam is a moisture-cured sealant – achieving full cure within 4-6 hours to produce a durable, high-movement elastomeric sealant. one of the greenest sealants, AirDam is packaged in traditional sealant tubes or sausage tubes to minimize waste. It requires standard caulking tools for use, and is easy to gun and tool in all weather conditions.
For detailed installation instructions on how to incorporate ThermalBuck with Prosoco FastFlash liquid flashing membrane and Spray Wrap MVP fluid-applied air & water resistive barrier, please contact us at thermalbuck@brincbp.com.
ZIP System™️ Liquid Flash
Photo sourced from Huber ZIP System™️ Liquid Flash brochure
With silyl-terminated-polyether technology (STPE), ZIP System™️ Liquid Flash gets its durability from silicones, toughness from urethanes. Becoming quickly waterproof after installation, ZIP System™️ Liquid Flash bonds and cures in wet weather, at temps from 35° F to 110° F. Available in 10.3 or 29 oz cartridges, as well as 20 oz. sausage tubes, Liquid Flash achieves complete cure in 4 hours.
Liquid Flash is ideal for both installing ThermalBuck, and flashing the window.
180 day UV exposure
Bonds & cures in wet weather, and on damp substrates
Passes ASTM E331, and E2357
Fasteners
Choosing Fasteners
ThermalBuck is installed not only with sealant, but secured through the 1/2″ tongue into the structure with 2″ galvanized roofing nails, in order to exceed the minimum 1-1/4″ structural penetration requirement.
Nails should be placed 10″-12″ apart. Insert nails close to the seams in each corner, and on any split pieces used on jambs. ThermalBuck can easily withstand use of a nail gun.
All fasteners must penetrate into the structure a minimum of 1-1/4″ for structural attachment.
Screws are recommended for installing the window. Install them at angle for better attachment to the stud, since ThermalBuck has moved the window 1/2″ outwards from the stud.
If you’re using a thicker depth of ThermalBuck and want to use a low profile screw, you might need to order ahead. #10 diameter are preferred. Purchase from your local building material supplier, or direct from manufacturer. We’re big fans of these Grip Deck screws from the experts at Rodenhouse.
Screws are recommended for the window installation.
2″ roofing nails for the tongue.
Fasteners must penetrate through ThermalBuck into the structure min 1-1/4″.
Side-by-Side Windows
Side-by-Side Window Installation
Home designs often feature several windows side-by-side. Think above the kitchen sink. It’s important to consider the dimensions of ThermalBuck, and how it impacts the amount of space needed between the windows.
While ThermalBuck comes in 7 different depth to match the continuous insulation and/or rainscreen, the width that extends past the rough opening is consistently 2.0″. If you have side-by-side windows, you’ll need at least 4.0″. Most framers use two studs, and have only 3.0″ to work with between side-by-side windows. It just won’t fit.
When planning side-by-side window installations with ThermalBuck, a minimum of 4.0″ between windows is needed to accommodate the ThermalBuck from each window.
Now that doesn’t always happen in real life, so we’ve figured out a solution if you’re left without enough space between rough openings (see how to solve this challenge below). You’ll make everyone’s day go a lot smoother if you just leave enough room between the windows in the first place.
Splice each piece of ThermalBuck lengthwise. Leave extra room for sealant.
Cover the exposed EPS with generous amounts of sealant & flashing tape.
Fill in any wide gaps with spray foam, and a wide bead of sealant on top. Cover entire seam with flashing tape for added protection.
Shims
Shims
Preferred placement of shims is under the sill plate of the rough opening. Many window manufacturers recommend this so that the window is completely supported on the sill.
In some instances, the only option will be to shim on top of ThermalBuck.
Place one square inch of shim material for every 40 lbs. window weight (example 120lb. window one shim at each corner 1.5” x 1”) on top of the ThermalBuck.
Consult the window manufacturer for their recommended shim placement.
“Innie” or Flangeless Windows
Innie Windows
ThermalBuck was originally designed for nail flange window installation. Our performance testing, and installation steps were developed using nail flange windows, attached to the structure through the outermost part of ThermalBuck.
However, many architects and builders who prefer innie or flangeless windows have seen enough value in the thermal break provided by ThermalBuck, that they have developed their own installation techniques.
If you’re considering ThermalBuck with an innie window application, please reach out to us at 888.814.2825. We’d be happy to share more information.
Installation featuring ThermalBuck, Yaro windows, and Rockwool Comfortboard exterior insulation submitted by 377 Builders, Massachusetts.
Arched Windows
Arched Windows
Plato said that “necessity is the mother of invention”. If you try to use ThermalBuck in an arched rough opening, you’ll agree with Plato wholeheartedly.
Some of our more industrious customers have developed unique methods to approach arches, such as this builder in Oregon.
He cut the lengths of ThermalBuck in half lengthwise, then into smaller blocks. He seamed them back together as a “top” and “bottom” piece on either side of the arch.
If you’re going to “step outside of the box” with ThermalBuck, we’d suggest plenty of sealant, and a layer of flashing tape. No matter what method you use, making sure it’s airtight & watertight is the goal.
If you’ve tried something unusual with ThermalBuck, we’re interested. Send us your photos and testing to thermalbuck@brincbp.com . Maybe we’ll learn a thing or two.
Energy-efficient custom home build in Eastern Oregon featuring 2.5″ ThermalBuck, R-Max Polyiso exterior insulation and Andersen Architectural Collection.