How to repaint a large concrete deck?

[hurlexx]

Hi, im looking to repaint/renovate my large concrete deck (approx 55sqm) and am open to suggestions of ideas, products and applications. The deck was painted professionally 7ish years ago however has began to show age with cracks and paint from renovations, and  mainly always looks dusty/dirty. (Overall in good condition, photos attached of damage).

With no expasion gaps across the deck, there are multiple hairline cracks (5 or so), and would most likely appear no matter the finished product?, in this case, I'm interested in a product with texture or depth (not flat) to help hide this.

I've got the tools and the relevant experience to handle the project so am open to ideas!

Thankyou!!

 

  

 

 

 

   

[EricL]

Hello @hurlexx 

I would recommend starting by removing all loose, flaking or damaged paint to make sure your new finish adheres properly. A paint scraper and a stiff bristle broom usually do the job, though a light sand can help feather out any raised edges. Once the loose material is cleared, give the entire surface a thorough clean to remove dust, dirt and any contaminants. A concrete cleaner or sugar soap works well, followed by a good rinse and time to dry.

For the cracks and worn areas, a cement-based patching compound such as Earl's 1kg Concremate Expanding Cement is ideal. It allows you to fill hairline cracks and small depressions so the surface is even before coating. After patching, you can lightly sand the repaired spots and then prep the whole deck according to the requirements of the coating you intend to use.

Regarding whether the existing paint needs to be fully stripped, that usually depends on how well the remaining coating is bonded. If most of the paint is still sound and only small sections are failing, you can generally clean, patch and then prime the surface before applying your new finish. Full stripping is only necessary if the old paint is peeling extensively, chalking heavily, or lifting in large sheets. From the photos, the coating looks mostly intact, so a full strip may not be required.

I understand that you are after a coating that has texture or depth to hide any cracks or damages your floor might have.  But if you were diligent with your repairs, none of the damages will be visible as you've covered them up with Earls cement patch. It is possible to add anti slip additives to the White Knight White Heavy Duty Ultra Pave Concrete And Paving Paint - 4L in order to give it a less flat look and provide grip when you walk on it. There is also the Rust-Oleum 3.78L Battleship Grey Concrete And Garage Floor Paint along with Berger Jet Dry 4L Deep Charcoal Heavy Duty Paving Paint. 

Here is a handy step-by-step guide: Ultra Pave - HOW TO

If you need further assistance, please let us know.

Eric

[hurlexx]

Hey Eric thats some great information thankyou! 

In the below picture approx 3m by 2m wide the concrete has a fall towards the house while everywhere else slopes away. My plan is to grind and prep and self level the area and feather the edges, or would it be easier to cut expansion grooves in and self level to those edges? (From the first post in the photo to the end of the goarse door approx)

[EricL]

Hello @hurlexx 

I would go with your plan of grinding and prepping and self-levelling the area and feathering the edges. I don't recommend cutting expansion grooves as it is a solid piece of concrete and you don't want fissures to develop on this solid slab.

Eric

[hurlexx]

No worries,

Would that be feathering it to the edge/drop off and how would i not allow a lump or slight ramp/jump from both ends of the self leveller back to the original concrete?

I appreciate the advice

[EricL]

Hello @hurlexx 

This is the tricky part; my best advice is to use several builder's line to create a guide while using the self-leveller. In this manner you won't have to second guess yourself while feathering the compound. Plus, you know that water will flow away from your house.

Eric