A key point in the sustainability of your playhouse is of course the protection that you will apply to your wood.
As discussed in this article on how to build a cabin, certain types of wood may well be without protection as the robinia, for example, naturally rot.
Of course this is not the case of other wood, especially pine which must be treated regularly especially if it is facing north.
The wood placed on the outside will be faced with two main enemies:
Light: Ultraviolet will somehow burn wood and make it lose its natural color and become gray.
The final stage of this process will cause cracks and cracking wood, is nothing too serious in the structural level, but aesthetic.
The second enemy of wood you guessed is the humidity, more problematic than the sun because in addition to swelling the wood it will set up a breeding ground for mushrooms.
If rain water does not flow or does not evaporate quickly, it will just seep into the wood through capillary action and will increase its humidity.
Then appear lignivore, precursor of mushrooms which will attract insect damages.
Needless to say that to this stage your playhouse will have the strength of a wet cardboard construction, so it is necessary first to make arrangements.
Treatment with linseed oil.
Very cheap linseed oil supplemented with a little turpentine forms an excellent solution for your waterproof wood.
Its really low cost makes it one of the most used protections in France for hundreds of years.
As its name suggests, the humidifier will soak deep into the wood to give it greater resistance to humidity.
A little more expensive than linseed oil, it is however much more effective on horizontal wood.
The wood retains its original color without gloss.
Microporous stains allow the wood to “breathe”, some fungicides and insecticides compounds are included in its composition which make them ideal as a preventive treatment.
Their sometimes prohibitive prices can sometimes put off and their effectiveness is not necessarily superior to flax oil treatment.
My advice: Go for a linseed oil treatment diluted with turpentine, apply as many coats as necessary to complete saturation of the wood.
An average 3-4 coats are required to be spread over two days by hot, dry weather preferably.
Finish with a pure flax oil layer and your wood will be protected for at least 12 months.
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