suspended floor joists should they be treated timber

26 Apr 2008
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United Kingdom
hi, hope someone can help i am laying new suspended floor joists should they be treated timber, its a new extension they are on hangers with dpm and concrete oversite below, any help would be much appreciated
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Almost all timber available at timber merchants is tannalized now, especially for joists, this will prevent infestation in the future.
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Another useful thing to remember is that not all preservatives give the same protection.

So for instance, if the local merchant uses timber done with something like Protim E415 (yellow colour timber) then it does not give the same protection as say Tanalith salts (green colour timber).

And the actual process gives differing results too,

So just because timber is sold as treated, it does not mean it is suitable for all particular situations
Thanks Woody for the info wasn't aware of that! thought the treatment was standard. Is there a study to determine the effectiveness of the various treatments?

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