Specification Sheet

DATA TEC
Log Builder Caulk
All logs move, so Log Builder was specifically
designed to absorb most log movement. Most movement
occurs within the first few years, when logs lose the
majority of their moisture causing them to shrink and the
joints to expand. That’s why it’s crucial to use Log
Builder from the start. If the logs are extremely “green”
(with very high moisture content) it is often best to wait
several months before caulking. Since it stretches and
compresses up to 100% of the original joint size and
stays elastic, Log Builder won’t crack, peel or pull away
from properly prepared logs. Instead, it creates a tight
seal to keep water
, dust, bugs and wind from seeping into
your home—for many years. Log Builder is the smooth
sealant for milled and hand-crafted log structures.
Fundamental Caulking
Application Guidelines
• Proper substrate preparation and application are imper-
ative for product longevity. Read this entire Data Tec
(LBR 002) before applying any product.
• Make certain there is compatibility between your
stain and Log Builder. We recommend Sashco’s
Capture/Cascade, High Sierra or Transformation stains
for exterior applications and Symphony interior clear
coat for beautiful long-term protection. Best results are
obtained when Log Builder is applied to clean, stained
wood. Call Sashco at 1-800-767-5656 for guidance if
in doubt.
• Check the weather forecast. Finishing products are
best-applied in moderate weather conditions, i.e., out
of direct sunlight, in dry, warm conditions..
• Check the log surface temperature. The surface tem-
perature should be between 40˚F (4˚C) – 90˚F (32˚C).
• It is always best to use a bond breaker (usually backer
rod) before caulking. Sashco strongly recommends the
use of backer rod, especially if the home is new and/or
the logs are subject to significant movement. If a bond
breaker is not used, then expect more caulking repairs.
• Tool Log Builder to help ensure good contact with the
log surfaces, especially to the upper log; this will
greatly aid adhesion.
• Ideal sealant depth is 1/2 of the joint width, but no
less than 1/4” and no more than 1/2”.
• Assemble tools and equipment:
- Backer rod
- Caulking guns
- Trowels, spatulas, or foam brushes for tooling
- Clean water and rags
- Plastic sheets to cover the caulking if wet
weather moves in
- Staple gun & staples
• If you have any questions about application, please
call us before proceeding at 1-800-767-5656.
Surface Preparation
Best results are obtained when Log Builder is
applied to wood that has been previously coated with a
compatible and thoroughly cured stain. In fact, Log
Builder has a Limited Lifetime Warranty when applied
over any of Sashco’s stains: Capture Log Stain, High
Sierra Log Stain or Transformation Stain. Call us
for details on this special warranty – the best in
the industry!
If not using a Sashco stain, be sure to confirm its
compatibility with Log Builder. If the stain is older
but still intact, clean the log surfaces thoroughly to
remove dirt, pollen, bird droppings, and other
surface contaminants.
The USDA Forest Products Laboratory and other
researchers around the world have recently reported
that surface wood exposed to sunlight for as little as
1-2 weeks can become significantly damaged and
unsound which may lead to premature adhesive
failure of coatings. Such surface wood damage has
the potential to also hurt Log Builder’s (or any caulk’s)
adhesion. Once bare wood has been properly cleaned
and prepped to remove unsound wood, stain should
be applied as soon as possible. Follow with
Log Building caulking.
A few sealers, especially those high in wax content
or non-drying oils, may interfere with adhesion. Some of
these coatings can hurt any caulk’s adhesion—whether
applied before or after the caulk—so we advise against
their use. Check with Sashco if you have questions
about your particular product.
10300 E. 107th Place • Brighton, CO 80601
1-800-767-5656 • 303-286-7271 • www.sashco.com
04-09
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Technical Data
(Not to be considered specifications)
Colors
Tan, Woodtone, White Pine, Dark Brown, Gray,
Redwood and Black
Packaging
10.5 oz. plastic cartridges, 29 oz. fiber cartridges, and
5-gallon straight-sided pails. (Not all colors are avail-
able in all sizes.)
Application Range
Surface temp of 40˚F (4˚C) - 90˚F (32˚C)
Service Range
-30˚F (-34˚C) - 250˚F (121˚C)
Paintability
Paintable with latex coatings after a minimum of 24
hours curing (longer on wider joints) and after 5 days
with most oil-based coatings. Contact Sashco for
more specific guidance.
Compatibility
Log Builder will adhere to woods treated with
most preservatives including borates**, pen-
tachlorophenol, and copper compounds. Log
Builder is also compatible with insulating glass
sealants and most building materials, including
foam insulation and vinyl windows.
** Some borate wood preservatives contain glycols
or other agents that could interfere with adhesion.
Sashco’
s PeneTreat contains no glycols.
Specifications
Passes ASTM C-834, the performance requirements
of
TT-S-00230B and ASTM C-920.
Meets FHA requirements.
VOC
4% by weight, max.
Cure-Thr
ough Time
3 weeks (1/2” thickness, 70˚F, 50% relative humidity)
Extrusion Rate
1100 g/min (1/8” orifice at 40 psi)
Fr
eeze-Thaw
Passes 5 cycles (0˚F - 70˚F)
Hardness (Shore A)
38 (21-day cure)
Elongation @ Break
550%
Solid Wt. %
79%
Solid Vol. %
71%
Tack-Free Time
Less than 1 hour
Stain
None
Water Resistance
No washout (4 hours, 40˚F, 50% relative humidity)
In severe conditions - under 40˚F (4˚C) and/or 70%+
humidity – full rain resistance may take longer
. Cover
exterior walls with plastic if rainfall is expected with-
in 24 hours after installation.
Not recommended for continuous submersion or
areas exposed to foot or vehicular traffic.
Weathering
Washout None
Cracking
None
Discoloration Passes ASTM C-834
Notice
Sashco will test any stain to determine compatibility
with Log Builder. Just call and send us a sample of
the stain you want tested. Test results available in a
minimum of 6 weeks.
The data reported here are believed to be reliable. No
warranty is made or implied concerning the accuracy
or the results obtained from their use.