KDAT and TWP Wait Period for New Wood

With newly installed treated lumber, it is necessary to wait an adequate period of time for the wood to season or dry out prior to staining it with TWP. New wood sometimes referred to as “green” wood, has a very high moisture content when it is new. Staining wood in this condition would trap moisture under the stain and potentially lead to mold, mildew, and wood decay issues. This can mean premature future costly repairs and replacement of the wood so it is best to wait. The seasoning time frame can be around 4-12 months give or take depending on the climate, weather and sun exposure.

To avoid having to wait months to stain your new wood you can use KDAT wood instead. KDAT (kiln dried after treatment) is wood that is dried in a kiln after it has been treated with the proper bug deterring chemicals. The wood is then put on the market and sold. It is slightly more expensive than regularly treated wood but it may be worth not having to wait as long to stain it. The wait time for staining new KDAT wood with TWP is about one month. This cuts down significantly on the wait time and may be the right option for you.

After the month waiting period for KDAT wood, you should prep the wood with Gemini Restore Kit. This will clean the new wood and remove any mill glaze that occurred during the sawing of the wood at the mill. If mill glaze is left on the wood it can hinder proper penetration of the TWP stain and jeopardize its longevity and performance. Always clean and prep new wood just as you would older lumber.

Whether using KDAT or standard treated lumber, be sure the moisture content of the wood is below 15% before applying TWP stain. 

Staining New Wood and Decking for the First Time

Even after the waiting period and the proper prepping, new smooth wood is still not as absorbent as it will be in a few years. We strongly suggest only applying 1 coat of the TWP Stains the first time. Do not over apply as the TWP may not penetrate into the wood correctly. Make sure to back wipe any excess stain that does not penetrate properly into the wood after 30 minutes. Use the For newer wood, TWP 100 Series if allowed in your state, otherwise use the TWP 1500 Series.

Maintaining TWP Stains

Apply a light maintenance coat to the flooring in 9-24 months. If just slightly dirty prep with soapy water to remove grime and reapply one light coat. If you wait 18-24 months make sure to prep again with the Gemini Restore A Deck. After the first year or two, your wood will be able to absorb more TWP stain which results in a longer stain life and protection!


TWP is a penetrating wood preservative. It performs properly when it penetrates 100% into the wood. Over applying will not result in longer protection.


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6 Comments on "KDAT and TWP Wait Period for New Wood"

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Help! We want to stain the porch floor on our 117 yr old house. We are getting ready to have porch floor sanded to remove existing paint & we’re hoping to stain next week. We did have to replace about 20 boards & did so with Kiln dried fir on 9/18 (exactly a month ago next tues). I’ve been told by a couple of people we need to wait until spring for those new boards to weather. A couple of people said we should be ok to stain now. Reading the info. above indicates we can stain now. Torn on… Read more »

It may have been stated before, but I am in western New York State, and wonder if I need to use your prep kit on this new deck(KDAT). The deck is 5 days old. Can we stain now, or do I need to wait a full month, and then will regular washing be enough???


I thought I read that you recommended 1 coat for new KDAT pine, but in calculating amount needed you state 2 gal. for 2 coats of wet on wet? So which is best, 1 coat now, and 1 coat later(?) or 2 coats now?