Generally speaking a Total of three coats are sufficient. Which is One coat of Sealer, and Two coats of Polyurethane, which equals a Total of 3 Coats.
Yes, the Sealer Coat counts as a Coat.
There are a number of advantages and disadvantages when using a Sealer coat as the first coat.
Advantages :
1. Its Quick dry and allows you to get two coats on the first day......Speed.
2. It forms a bond breaking Seal, to help prevent edge bonding. (A myth made up by water based companies)
3. It preserves the true natural colour of the Timber.
4. It does not need to be sanded back. (Sandable Sealers are a waste of time.)
Disadvantages:
1. Cost. A quality Sealer is a little more expensive than just thinning down your first coat of polish.
2. You need to work fast. People who aren't efficient at coating tend not to use Sealer as they can't apply it fast enough.
Both of these are not issues to Licenced and highly trained Professionals.
So why do some companies still just thin down the first coat and use that as a Sealer. Well usually Cost and they are not efficient at getting the coat down swiftly.
Disadvantages:
1. You don't have a bond breaking seal and could be prone to edge bonding.
2. Putting Polyurethane directly on raw timber darkens the colour immediately.
3. Takes a few hours to dry. (Which means adding an extra day to the job.)
4. It furs the Timber up and Has to be sanded back before applying 2nd coat.
Advantage:
1. You might save a few pennies.
2. If you're slow at coating its more forgiving than Sealer.
In summary a well trained Professional will always use a good Quality Sealer as the First coat, and follow up with two coats of Two-Pack Polyurethane.
You only get what you pay for. If you get a really cheap quote for sanding and polishing, there are a number of reasons.
1. They use the cheapest quality polish. (Is yellow in the drum)
2. Frequently they skip the Sealer coat and try to Flood Two Straight coats. It looks thick and nasty.
More thin coats are far more desireable than fewer Thick coats.
Just like painting a Ferrari. It has 10 thin coats. Not Two thick ones.
For high end homes, if you can afford it, why not spoil your floor with a 4th Coat.
It will last longer and be smoother and more beautiful as we can sand back between the coats more aggressively if we know there are 4 coats going on.
The Sanding back between the coats is the key to a professional finish. See The Perfect Process video to see how we do it.
“The Perfect Process will transform your timber floor.
Quicksand & Polish @ Qsand - The difference is clear.”
- Mark Jolley, Vanguard
