Earlier this month, we gave an in-depth look at the Exterior Painting Prep process. Today we would like to share Bend Custom Painting & Refinishing’s guide to Exterior Staining Prep. Staining and painting wood require very different steps to the preparation, so it is important to distinguish between the two. We hope this post is informational and enjoyable!
Wood Brightening
Wood brightener is your best friend when it comes to prepping any surface for staining. Typical surfaces include: decks, trim boards, railings, beams, and sometimes siding. Wood brightener works on all of them! So what does it do? Essentially wood brightener is a chemical compound that soaks into the wood, penetrating deeper than the existing stain (it is also beneficial for non-stained surfaces). Once the chemical penetrates the wood, the pores expand, helping to dissolve the bond between the existing stain and the surface. This allows for easier removal of existing stain (especially if it is beginning to fail). For new wood/non-stained surfaces, the brightener still helps to open wood pores, which aids in stain absorption.
Application:
-Prior to applying the brightener, you will want to give the surface a light wash with a pressure washer. The application process will be more effective when the surface you are working on is wet first (a regular hose spray nozzle will work fine as well).
-Using a backpack sprayer, the detergent hose on your pressure washer, or a handheld sprayer (typically used for spraying for insects or weeds), you will mix 3 parts water to 1 part brightener (follow directions on bottle).
-Applying the brightener to ALL surfaces being stained is recommended. Be sure that the entire surface is covered with the application (small puddles will form and slowly dry up). A RESPIRATOR MASK IS RECOMMENDED (the chemical can make you cough if inhaled at all).
-Using a hand or pole brush (soft bristles), scrub all surfaces that you have applied the brightener to. This will ensure full penetration of the compound, and will begin to remove existing stain.
-For heavily stained/charred/mildewed areas, a second coat of spraying application after the scrub is recommended as an extra step towards full preparation of the surface.
-Let brightener sit 15-20 minutes, then use a pressure washer to thoroughly rinse all surfaces off. Get as close to the surface as you can with this wash without damaging the wood (which is easy to do in this stage). The cleaner the wash, the less prep you will have later.
-Let all surfaces dry 2-3 days (depending on weather). Do not commence any further prep until surfaces are fully dried; otherwise the surfaces will not be ready to absorb stain.
Sanding
Once all surfaces are brightened, cleaned, and dried, you are ready for the part that is the most fun: sanding! Just kidding, sanding is the most arduous part of this entire process, but is fully necessary if you wish your stain job to last longer than a few months (especially here in Central Oregon). When stain starts to fail, it opens the wood up to damage from the elements, and it essentially becomes useless. That is why it is recommended that all decks (and most stained surfaces) be refinished every 1-2 years.
What is the difference in this time span between stainings? Sanding.
Sanding Tips:
-You will absolutely want a power sander of some sort. At Bend Custom Painting & Refinishing, we have three sanders we use: the hand detail sander, the hand orbital sander, and the floor orbital sander. Each of these serves a specific purpose: the detail sander is for tight corners, final sanding touchup, and in between deck boards; the orbital sander is great for railings and trim, and can also be used on the deck boards (for smaller decks); the floor sander is for larger decks.
-The two hand sanders are fairly affordable and can be purchased at any home improvement lot store. If you can only purchase one, opt for the orbital, as it has many functions. The floor sander can be rented from many tool warehouses for usually around ~$50/day.
-Sanding is recommended in 2-3 stages, in terms of the coarseness of the grit of the sandpaper. Usually, you will want to start with 40 grit sandpaper for most surfaces that have existing stain (if there is no stain or it is new wood, once over lightly with 80 or 100 grit sandpaper will be sufficient). The first time through, you are really taking your time to remove as much of the stain as possible. It is important to notice how much wood you take off the surface, because 40 grit can really grind down the wood quickly.
-The second pass of sanding should be with 60 grit sandpaper and is more used for catching all the edges that were missed and evening out where you may have taken off too much wood.
-The final pass should be with 80 grit sandpaper and is designed as a finish coat. You are looking for a smooth and even surface for all areas you are staining.
Blowing Off
It may seem silly to include this as a step, but it is extremely important. Blowing off the surfaces you are staining once you have sanded is crucial to stain absorbing properly. You want to use a leaf-blower or the like to remove all wood and stain dust particles that you have created from sanding. Literally you want to be able to eat off of your surfaces, so check by rubbing your hand over many different areas just to be sure. If you don’t have a leaf blower, renting one is fairly affordable as well.
Masking
Although not always required (especially for decks and rails), masking can help save a lot of cleanup time and so is usually recommended. You will want to use a high quality tape (we use Frog Tape here at BCPR) to have definitive lines between your stained surface and non-stained surfaces. Once the lines are in place, using 18 inch wax masking paper or 24 inch masking plastic should be sufficient for most jobs. Be aware: stain may still leak through if dripping becomes too heavy.
Be sure to tack down the back edges of the plastic or the paper using any brand of masking/Scotch tape (Frog Tape is not necessary here).
Check Surroundings
If it is too windy, too hot (>90), or too cold (<60), you will not want to stain that day. Why? Wind causes leaves and other debris to fly through the air and land directly in the middle of your freshly stained deck. When it is too hot, it can be extremely difficult to get a nice even finish to your stained surface, because the product will dry as fast as you apply it (creating lines between strokes). When it is too cold, the stain won’t dry fast enough and can take days (allowing more time for debris to land on the surface, as well as moisture from evening cloud cover/morning dew to seep into the wood and mingle with the stain).
You'll also want to check that branches aren't overhanging surfaces to be stained, along with other plants being right against the surface. Trimming back beforehand can save a lot of headache later.
When you hire BCPR, we are trained to deal with any condition, and will always advise you if weather does not permit our staining that day. However, when you do not have a team of trained professionals to stain for you; there are many risks you will face.
Staining
We will go into further detail on the staining process, as well as what stains to select for what surfaces, and what products we at BCPR recommend in future blog posts. Stay tuned! Until next time.