Generally the duration of the finish is dependent on three items:
1) Design of the home (How much of the home is protected from UV by overhangs and plants.
2) How well are the logs prepared for painting
3) How well is the coating applied
Here is the theory behind Hemp Shield and why we think our tests show such superior performance—
The coating is designed to have high solids and low viscosity. The Hemp emulsion has a very small particle size and is able to penetrate deeply into the wood surface. The emulsion carries with it large amounts of UV absorbers, biocides, trans-oxide pigments, and wood stabilizer. This material fortifies the wood against UV light, bacterial damage, and erosion longer than a simple coating on the surface which peels or washes away. Average lifespan we see has been 3-5 years from one coat on cedar, pine, fir, and redwood.