Timber must be protected form weather elements, mainly form rain and Sun’s damaging UV rays.
To protect the building from water damage, preserve the timber or at least bottom boards with a CN (Copper Naphthenate) timber protective emulsion. Read instructions and watch video of preserving the first layer of the structure. Sealed bottom boards will stop any moisture penetration that comes from the top of flashing installed around the perimeter of the building.
Another important waterproofing point is the roofing. Make sure corrugated roofing is installed according to the roofing manufacturer’s instructions with sufficient rain gutters and down pipes to dispose of rainwater.
After the assembly of timber parts is finished, cover your new building structure with the waterproof sheets even it is only for a night. Roofing must be put on as soon as possible to waterproof the building and avoid water damage to the timber.
Sealing the timber with paints or stains
It is important to seal [paint or stain] the timber surfaces inside and out using quality timber paints within 21 days after the assembly process is finished. Window/door architraves and fascia boards must be painted from both sides. Unscrew the architraves, seal all timber surfaces and screw them back. Seal all timber surfaces of fascia before installation.
Natural timber cracks, holes need to be filled with the timber fillers to get an even surface for a perfect finish. Also, any surface imperfections should be sanded and sharp edges rounded. This will ensure better coverage of paints and protection. On average, you will have to repaint it every 10 years or re-stain it every 2 years, but this will depend on how the timber is exposed to the weather elements. Please refer and follow the paint manufacturer’s instructions.