Loba Wakol PU 280: Stop Moisture From Ruining A Floor

WAKOL PU 280 is a one-component, roll on system with zero VOC that provides inexpensive insurance against moisture issues.

One of the best benefits of this roll-on product is that you can see the coverage as you roll it on due to a blue tint. This makes it easy to locate any missed spots for touch up.

Watch our full Pro Shop Talk episode about everything you need to know about using WAKOL PU 280.

How to Best Apply Wakol PU 280

Wakol PU 280 is fast drying and easy to apply, giving you complete moisture coverage and allowing you move onto the next step quickly. Because it dries fast, you don’t have to prep days in advance, even if there’s a lot of humidity. Two coats on 1000 sqft. could take you as little as two-and-a-half hours to apply and dry. After that, you can start installing immediately.

A recommended workflow: Clean and prep the subfloor the night before, apply PU 280 first thing in the morning. While it’s drying you can get your tools ready, then start installing once it’s dry.

To apply Wakol PU 280, follow these steps:

  1. Make sure that the subfloor is clean, dry, flat, and sound.
    • Fill any cracks or slab seams and complete any grinder work on high spots at this point.
    • For concrete subfloors, Loba-Wakol recommends using their concrete prep tool with a 16-inch buffer to prepare the slab. With the buffer you can remove contaminates, paint overspray, and abrade the surface, which opens the pores for maximum bonding of leveling compounds and adhesive.
  2. Sweep and vacuum up all debris.
  3. Prepare the PU 280 product by shaking the pail for 30-45 seconds. Open and fill the WAKOL Proportioning Pail with the required amount.
  4. Apply your first coat of PU 280 with Loba’s 60-80 quarter-inch nap roller or any size from quarter inch to half inch. Apply in cross directional pattern – overlapping north to south, then east to west – ensuring complete coverage.
  5. Allow to dry for 40-45 minutes.
  6. If applying a second coat, roll it out in a thin layer in the same cross directional pattern as the first coat.
  7. Let second coat dry 40-45 minutes.
  8. Start installing!

Application Tips

  • The most common issue people have is putting on more than they should. More is not better with this product. If too much is applied, it will bubble and seal upon itself. Instead, you want to “dry roll” using just enough product to cover the slab. Work it in into the concrete with some roller pressure, rather than leaving a thick layer. As long as you can see a blue tint you are getting good coverage, and if you missed a spot, it’s easy to go back over.
  • The second most common issue: getting PU 280 on areas you don’t want it to be. Once PU 280 dries, you can’t get it off. Tape off baseboards, doorways, and put cardboard down where you will be walking – on the front porch, back porch to minimize leaving a permanent footprint. If you find a spot of PU 280 on something, you only have 45 minutes to clean with mineral spirits.
  • The first coat will penetrate the substrate bonding to the slab. Adding a second coat will fill in any micro voids left unfilled from the first coat and will adhere to the first layer providing additional moisture protection.
  • PU 280 dries quickly – wipe off the lid of any product before you screw it back on so that you will be able to open it and use the remaining product.
Watch WAKOL’s quick walkthrough of applying PU 280 to a concrete subfloor.

What if there are cracks or seams in the subfloor?

For a wood subfloor, locate any problem areas to be fixed. This is where WAKOL’s MS 245 Montinator can be helpful. Close up cracks so that moisture can’t get to the flooring.

For cracks in concrete, clean the slab and use WAKOL PS 205 or MS 315 to fill them. For a deep crack, use a cement filler or patching compound before the applying PS 205.

Is moisture testing required when PU 280 is applied on new construction?

For new construction, WAKOL requires that all slabs be at least 20-days old with an intact working vapor barrier underneath the slab.

When moisture testing, make sure to test the layer that has the PU 280 applied. To be sure that the PU 280 is doing its job, conduct a calcium chloride test. Do one before and then after applying PU 280 to see the difference.

Try this life-hack: water bead test. Put a dime-sized drop of water on the subfloor with the first layer of PU 280 for 45 seconds. If there is no change and it isn’t absorbed in the slab, the PU 280 is doing its job, so you’re good to go.

How would you use PU 280 on a wood subfloor like plywood or OSB?

Important note: you’ll get less square footage from one pail of PU 280 on a wood subfloor versus concrete. The average for concrete is 1,000 sqft per pail, and for a plywood or OSB subfloor it drops to around 700-800 sqft per pail. Remember: don’t apply it too thick.

Additionally, when using PU 280 over a wood subfloor, expect a similar level of protection to a paper vapor retarder. When used on plywood subfloor it should be considered a moisture retarder not a moisture barrier. However, the benefit of PU 280 versus a paper vapor retarder is that PU 280 gives you more protection around the walls of the room. You can roll it wall to wall, in hallways, and hard to reach places.

Dust reduction is important and using PU 280 can help reduce jobsite dust better than paper vapor retarders. When using a liquid moisture barrier like PU 280, dust is sealed in and gives an overall cleaner substrate to work on.

What about when applying over gypcrete?

When using over gypcrete, only apply one layer. This is because you want some moisture to come through, otherwise it may deteriorate over time.

How would you level a concrete subfloor after using WAKOL PU 280?

The general steps are:

  1. For hairline cracks, use the WAKOL Substrate Prep Tool with the WAKOL PS 205 or 315 crack filler.
  2. Once those are taken care of, roll on a layer of PU 280 and let that dry. Apply the PU 280 first so that moisture is controlled at the lowest level.
  3. Apply a layer of WAKOL D 3045 Special Primer. It’s like a liquid sandpaper and will bond to the PU 280 and provide a surface that the leveling compound can adhere to. One jug covers a thousand square feet (so very affordable). Allow the D-3045 to dry, typically about an hour.
  4. Next step is to level the subfloor with WAKOL Z 615 level compound or WAKOL Z 631. Once your subfloor is leveled and dry you can start gluing down the floor.

It’s best to stay within the system of the same company so that you’re warrantied throughout the whole system.

WAKOL PU 280 dries fast so that you can move on to the next step within hours. Keep reading for tips about gluing over PU 280.

How long to wait after applying PU 280 before gluing?

PU 280 dries quickly, so you can start gluing as soon as it dries. If you aren’t able to install the same day you apply it, WAKOL allows up to 72 hours to glue down a floor. Beyond that the product can often get contaminated from other trades work. If your adhesive isn’t sticking, there’s a good chance there’s something on the subfloor.

What products can be installed over PU 280?

Any flooring can be installed over it – hardwood, LVT, linoleum, or carpet. It can also work for any installation method, glue-down, float or nail. PU 280 also works with all of Loba WAKOL’s products.

My customer doesn’t want to pay for a moisture barrier. What should I do?

Some people get a bit of sticker shock at the container price and fail to see the long term value of protecting their floor from subfloor moisture.

It is best to look at the cost per square foot, which is really a fraction of the overall price for the level of protection it provides. It’s a small price to pay over the cost of replacement later.

To use round numbers, let’s say it costs around $200 per jug for 1,000 square feet – that’s 20 cents a square foot. Compared to a paper or plastic vapor barrier, PU 280 isn’t much more expensive for the added benefit. There’s little need to worry about moisture issues, which can be very expensive to resolve after the flooring is installed.

For a flooring business, all it takes is one bad floor to ruin a company. Using a moisture barrier like PU 280 is very inexpensive insurance for your business, your reputation, and your client.

For businesses that use it consistently, they trust the system so much that it becomes part of every job. When you look at it as a per square foot price, it’s inexpensive insurance that your job isn’t going fail now or in the future.

Find WAKOL PU 280 At Our Pro Shops

Visit our Locations Page to find a Pro Shop near you to place an order for PU 280. We’d love to answer any questions you have or connect you to a local Loba-WAKOL rep who can do jobsite training with your team.