? about existing stain on decks

[andye629 14]

hopefuly someone can help, i have gone to price a couple deck jobs which had stain already on it. sometimes the customer has no idea what kind of stain was applied and i was not sure by looking at it. i usually use either cwf or cuprinal. my ? is if u r not sure what is on the deck then what would u do. if i use cwf or cuprinal on an unknown product i am affraid it might peel off and cause more problems down the road. i would usualy think to strip it but there has to be an easier and cheaper way. maybe lol maybe not

[Beth n Rod 1,279]

Try a test spot (with permission) to see if you can remove the stain before quoting the work.

Beth

[Paul B. 523]

You are correct - Without knowing what product is on there, the chances are very good that applying new over existing will fail prematurely.

As Beth said, test to see what product will remove it.

The test should also give you an idea how time consuming the job will be in addition to knowing what your stripper material cost will be in calculating your final estimate.

There are ways to test solid paints to see if its an oil based or water based stain.

Testing is existing stain latex or oil:

One way to find out if existing sealer is oil or water-based is to make a "Test Kit". Mix a strong solution of caustic stripper (such as HD-80) and put it in a spray bottle. Mix a strong solution of brightener and put it in a second spray bottle. Put both bottles in a bucket, along with a stiff scrub brush. Label the spray bottles for safety purposes.

When you are doing your estimate, spray caustic stripper on a spot of the deck where the sun doesn't reach (this will be the hardest spot to get the old sealer off). Let the stripper dwell for about five minutes, and then scrub a little with the brush. Follow up with the brightener to neutralize the caustic stripper. Then rinse the area well with plain water. (This will eliminate leaving a dangerous puddle that the customers' pet might step in or lick.)

If the old sealer melted (so you could scrape off residue with your thumb nail) then the sealer was oil-based and strippable with the product you brought with you. If it did not, then the sealer was likely a water-based product.

[Aplus 525]

And if it is a latex product, and does not strip with the HD-80, politely decline the job and save yourself a major pain in the rear.