Noncorrosive, fire-retardant, structurally sound yet lighter than untreated wood, and resistant to mold, mildew, termites and rot-pressure-treated wood is perfect for outdoor projects like swing sets and decks. But until TimberSIL came along this year, the lumber hasn't been so human-friendly. In 2002 the Environmental Protection Agency started phasing out the longtime standard additive, green chromated copper arsenate, for residential use because it leached arsenic into the ground. Its replacement, alkaline copper quaternary, was less toxic but had a bad habit of eating away at metal fasteners, like nails.
TimberSIL employs sodium silicate, a mixture of sand and soda ash used since the 1800s in detergents and as an egg preservative. Lumber soaks in it under pressure, then bakes until an insoluble matrix of amorphous glass hardens throughout the wood. No amount of rain or wear will remove it-bugs can look, but they can't touch. $4.50 per 8-foot 2x4
TimberSIL has just recently become available in 20+ states across the country and the dealers and distributors are growing rapidly. Recently in 2008, TimberSIL was approved by the EPA as the ONLY non-pesticidal barrier product they have ever approved! TimberSIL also completed it's extended weathering Fire rating tests in late 2008 which qualify it to be used in wild fire areas in California as a building product. TimberSIL is a class A fire rated building product. Non-corrosive, Non-toxic, non-carcenogenic, can be used in ground contact, above ground,indoor or outdoor use. Go to timbersilproducts.com website to read more about all of the attributes of this amazing new building product.
For a DIY treatment, it appears that spraying a water based sodium silicate onto lumber and timbers then allowing it to dry does provide significant fire and bug protection. It will wash off in outside use if not protected.
I have heard of it just being sprayed with a garden sprayer on inside and out of log cabins, wood before construction and even completed 'garden shed' type buildings.
Sodium Silicate is also known as 'water glass' for a reason, it melts in water, so it needing to be protected from water only makes sense.
As a fun experiment with kids, get some sodium silicate (pint, quart, whatever - it is generally considered non-toxic, but still be careful), cover the bottom of a plastic pan or a cookie sheet well covered by plastic (and edges, so it does not run off) and let it dry.
Once dry, pick it up and let the kids see it is quite clear.
Then you can brake it, and it shatters similar to glass. Put all the pieces in a jar with a bit of water, and it will all melt back into solution. This cycle can be repeated because just the water evaporates.
... I have filed this under: Fun things my Dad did with me as a kid.
Sodium silicate is also used to make for a harder concrete surfaces like floors when applied after initial cure of the concrete (7 days, full cure is normally 28 days). I don't know how much but some concrete specialists I am sure can let us know. But it is considered a 'technical' piece of knowledge in that realm, so the local concrete firm might not have that knowledge ... nothing against them! No one can know everything even in their specialty.
I doubt it takes a lot.
Obligatory warning to normal folk: As always, be safe out there. Take appropriate precautions when using any potentially sharp objects, or chemicals of any kind.
Currently manufacturing TimberSIL moldings, shutters, etc…give us a call if you have question or if we can be of assistance (www.goodmoldings.com).