Log & Solid Timber Construction – NatureColor®

Application of NatureColor® Base Coat & Recoater

Log Types

There are many types of log building systems that are categorized by how the logs are shaped, what type of corner fitting systems are used and the wood species selected. (i.e. Hand scribed or Machine milled; Green, Air Dried or Kiln dried.)

The primary concern for wood finishing of log and solid timber construction is moisture. There are two primary areas where moisture may be present in a log; surface moisture and inner moisture. Surface moisture must be below 18% to allow oil-based coatings to penetrate and achieve the optimum bonding to the wood substrate.

When the inner moisture of the log is above 18% this moisture will migrate out of the logs, which could cause a penetrating film finish to lose its adhesion to the wood. In this case we recommend applying two coats of Base Coat and waiting one year before applying the Recoater to allow that inner moisture to migrate out of the wood.

Note: All outer and inner bark plus the cambium layer should be removed from the log prior to coating. As the logs continue to dry, these layers of the log will release from the sapwood and will lift any coating that is applied to these layers.

Design & Building Techniques

A design that keeps the water and sunlight away from the wood surfaces will result in lower maintenance, which will save the building owner time and money. Here is a list from “The Log Home Maintenance Guide” by Gary Schroeder.

– Plan with a “Maintenance Perspective”
– Good foundation drainage
– Sill (bottom) logs should be 2 feet above ground
– Protect log posts from ground moisture
– Keep exterior walls free from back splashing
– Use self draining notches at the corners
– Ventilation systems for moisture producing areas of the home (i.e. kitchens, baths, etc). Vent through roofing system whenever possible.
– Log ends that do not extend beyond the roof overhangs  Provide a minimum of 2-foot overhangs, 4-foot is better
– Install gutters and downspouts  Install flashing – dormers, chimneys, etc.
– Use Impel Rods
– Cap log posts on railing systems with metal
– USE A QUALITY FINISH

Preparation

Follow the instructions on the General Preparation Guide Sheet.

Application Methods

High Surface & Inner Moisture (GreenLogs):
1. Apply Wood Preservative or Borate treatment
2. Let log dry (6 warm months) 3. Follow Prep Procedure
4. One Coat of Base Coat
5. Wait 24 hours
6. One Coat of Base Coat
7. Wait 1 year
8. Prep Maintenance Procedure 9. One Coat of Recoater

Low Inner Moisture: (less than 18%)
1. Follow Prep Procedure
2. One Coat of Base Coat
3. Wait 24 hours
4. One Coat of Base Coat
5. Wait 24 hours
6. One Coat of Recoater

High Inner Moisture: (more than 18%)
1. Follow Prep Procedure
2. One Coat of Base Coat
3. Wait 24 hours
4. One Coat of Base Coat
5. Wait 1 year
6. Follow Prep Maintenance Procedure
7. One Coat of Recoater

Timing

Surfaces should be coated within two weeks of cleaning procedure, second coat within two weeks of the first coat and third coat within two weeks of the second coat.

If subsequent coats are extended beyond these parameters cleaning of the surface should be done per the maintenance preparation specifications.

Product Check

Prior to application, a test area should be done using product purchased for the project. Test will confirm the desired color has been achieved, dry times are within 24 hours and product compatibility is evident.

Batch Check

Batch numbers appear on the Gallon and Five Gallon containers. For color consistency always use the same batch number for the job. If different batch numbers exist, mix all batches together to assure color consistency.

Tools

NatureColor® Base Coat and Recoater perform best applied with a longhaired natural bristle brush. NatureColor® products can be sprayed, but always back brushed to work the product into the wood on the first coat and to even the pigmentation and film thickness.

Spray Specifications:
– Airless Sprayer
– Tip Size 5-15 to 5-17
– Pressure – 1000 to 1500 PSI
– Saturate surface with product
– Even application by back brushing

Tip: Keep the spray head no more than 12 inches from substrate.

Clean Up

Clean up spills and spatters immediately with mineral spirits. Clean tools immediately after use with mineral spirits.

Dispose of empty can or unused finish in accordance with state and federal regulations.

For Best Performance

– Keep material from freezing
– Do not thin or add colorants
– Moisture content of the wood should be no more than 18%
– Apply liberal coats
– Apply in direction of the grain
– Maintain a wet edge
– Saturate all end grains
– Apply when surface and air temperatures are between 50 ̊F and 90 ̊F.
– Avoid application of product when temperatures are expected to drop below 50 ̊F within 4 hours
– Avoid application when dew or moisture is present
– Avoid applying finish in direct sunlight or when surface is hot to the touch.

Notice

The information and suggestions for use made herein are based on research and experience of Structures Wood Care, Inc., and are believed to be reliable. Application and surface conditions are beyond Structures Wood Care, Inc.’s control. Liability, if any, is limited to replacement of product or refund of its purchase price at Structures Wood Care’s option. Proof of purchase is required. Labor or cost of labor is excluded. Buyers must determine for themselves, by preliminary tests or otherwise, the suitability of the products for their purposes.