Re-painting concrete floor


  #1  
Old 05-01-20, 03:16 PM
S
Member
Thread Starter
Join Date: May 2020
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Re-painting concrete floor

Hi,

looking to re-paint concrete floor in our cafe. Will I need to apply a primer first? Considering using Zinsser BIN primer, never done this before so thought Iíd best ask!

TIA
 
  #2  
Old 05-02-20, 02:09 AM
M
Forum Topic Moderator
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,228
Received 754 Upvotes on 659 Posts
Welcome to the forums Sean!

Usually you thin the finish paint down about 10% to use as a primer although repaints don't normally need a primer. Do you know what type of paint is currently on the floor?
 
  #3  
Old 05-02-20, 03:16 AM
S
Member
Thread Starter
Join Date: May 2020
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
This is the current paint https://www.ebay.co.uk/itm/151438085297

I applied that directly onto the top of Armstead floor paint - a mistake! Whenever I move any furniture now, it leaves visible marks on the floor. Itíll be a nightmare when we reopen. Iíve read that I should have primed the old paint job first. Iím now thinking two coats of Vinsser BIN, then repaint the floor. Good job Iíve got plenty of time on my hands at the moment!
 
  #4  
Old 05-02-20, 03:47 AM
M
Forum Topic Moderator
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,228
Received 754 Upvotes on 659 Posts
That is a water based coating, was your underlying paint oil base or epoxy?

I assume you mean Zinnser's BIN which is a pigmented shellac primer. It has great adhesion properties but if it's applied over poorly adhered paint - that isn't the fix. I'd probably sand the floor and then apply your Marlcoating industrial floor paint.
 
  #5  
Old 05-02-20, 03:58 AM
S
Member
Thread Starter
Join Date: May 2020
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
This was the original paint https://www.duluxdecoratorcentre.co....%3fq%3d5218781 , which I painted straight on top of

Is the marl coating water based? I thought Iíd seen it was oil based
 
  #6  
Old 05-02-20, 04:03 AM
M
Forum Topic Moderator
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,228
Received 754 Upvotes on 659 Posts
Ya, that was a solvent based coating. Water based paints don't adhere well to solvent based finishes. Aggressively sanding the floor will serve 2 purposes. It will remove any poorly adhered finish and promote good adhesion. Traditionally solvent based finished are tougher than their water based counterpart although oil paints aren't quite as good as they used to be and waterborne/latex paints have improved.
 
  #7  
Old 05-02-20, 04:13 AM
S
Member
Thread Starter
Join Date: May 2020
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
What would you recommend to sand it with? Itís quite a large area. Iíd rather not have to hire any equipment, this has turned into a much bigger job than planned haha! How far will I need to sand it? Would the Zinnser product be of any use after the sanding?
Thanks!
 
  #8  
Old 05-02-20, 04:22 AM
M
Forum Topic Moderator
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,228
Received 754 Upvotes on 659 Posts
An orbital sander would work good to sand the paint, obviously a larger one would be more productive than a smaller one. You want to sand enough to remove any poorly adhered paint. A scarifier [?] would also be an option, it would be used to expose bare concrete so you could start from scratch.

BIN has great adhesion and stain/odor sealing properties but I don't think it's rated for floor use [not saying it wouldn't work] but it won't magically lock down any poorly adhered paint.

It would be a good idea to contact Marlcoating and get their input.
 
  #9  
Old 05-05-20, 11:33 AM
S
Member
Thread Starter
Join Date: May 2020
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for your help Mark.

Would there be any sort of paint remover that might work on this? Iíve had a little look, the ones i think id need - for polyurethane - are quite harsh chemicals. Is it best left to a pro? There is also a tenant in the property above the cafe, Iíd worry about the fumes from the paint remover.

TIA
 
  #10  
Old 05-05-20, 11:44 AM
M
Forum Topic Moderator
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,228
Received 754 Upvotes on 659 Posts
It will probably take a caustic paint remover to the original paint but the latex paint you applied should come off easier. You might try a small area with a citrus based stripper and see how it goes. If you end up using a chemical stripper on the whole floor you'll want good ventilation to help remove the odor! Sanding is probably a better option.
 
  #11  
Old 05-05-20, 12:55 PM
S
Member
Thread Starter
Join Date: May 2020
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Could I aim to remove the latex paint, then apply a primer to the original paint? The repaint the floor
 
  #12  
Old 05-05-20, 01:11 PM
M
Forum Topic Moderator
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,228
Received 754 Upvotes on 659 Posts
Remove the last coat of paint is a given, I'd get the advice of the paint manufacture on how to proceed after that. IMO it would be best to forgo the latex floor paint and use the solvent base floor paint that was originally used.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: