Washers or Just Screws?

[theandroids]

Hey, all Just wondering if you need washers for installing 6mm boards like Norcros pro board, Wedi, Mamrox, Kerdi etc (not hardiebacker) Onto a solid wall?
How would you install 6mm backer board to a solid wall?
I Just don't want to order washers for nothing.

 

[Flintstone]

You need washers for any mechanical fixings with those type of board. 6mm needs to be stuck with a solid bed of tile adhesive. Only really suitable for overboarding a skimmed wall or alike. Thicker boards can be dot and dabbed then fixings through the dots and the dabs!

 

[Time's Ran Out]

Expensive for a bit of thin metal but well worth the cost.

 

[theandroids]

You need washers for any mechanical fixings with those type of board. 6mm needs to be stuck with a solid bed of tile adhesive. Only really suitable for overboarding a skimmed wall or alike. Thicker boards can be dot and dabbed then fixings through the dots and the dabs!

Thanks. So apply with adhesive and then screw with washer. What about wall plugs too or no need. Also what size screws do you use? What size trowel to apply tile adhesive or can I use construction adhesive in a tube?
Sorry for all the questions but want to get it right.

 

[theandroids]

Expensive for a bit of thin metal but well worth the cost.

Yup expensive and I won't use a lot.

 

[Time's Ran Out]

Always worth putting in a jam jar on the top shelf.
When screwing into a solid wall always need plugs.
8mm adhesive bed.
Screws long enough to get a good hold to substrate.

 

[Dumbo]

My favourite washers that I've used so far are the Jacko board ones .
Some washers I find are very flimsy

 

[theandroids]

Always worth putting in a jam jar on the top shelf.
When screwing into a solid wall always need plugs.
8mm adhesive bed.
Screws long enough to get a good hold to substrate.

Thanks.

 

[theandroids]

My favourite washers that I've used so far are the Jacko board ones .
Some washers I find are very flimsy

I ordered some of ebay, they look like ones you're talking about. No way was I paying £23.99 for 50 washers on the site I got the boards from. The boards where cheaper than the washers

 

[theandroids]

You need washers for any mechanical fixings with those type of board. 6mm needs to be stuck with a solid bed of tile adhesive. Only really suitable for overboarding a skimmed wall or alike. Thicker boards can be dot and dabbed then fixings through the dots and the dabs!

The store only just got back to me with this answer in regards to 6mm Norcros Insulation Board. I'm confused...

"We would recommend a 25mm screw without the need for a washer The best practice method of fixing these boards to a solid wall would be to use tile adhesive and screws"

I was going to use 6 x 60mm screws like you would use with 6mm Hardiebacker. Any thoughts?

 

[Dumbo]

I don't know the Norcross boards . But a 25mm screw that's not right for masonry

 

[theandroids]

I don't know the Norcross boards . But a 25mm screw that's not right for masonry

That's what I thought, 25mm sounded silly. Seems they just have people giving random info. Think I could use turbogold wood screws or do they need to be stainless steel etc?

 

[Flintstone]

I’ve never heard of norcross board so I don’t know about that. But it’s not a brand I’m fond of

 

[Andy Allen]

If Insulation board like marmox...then you definitely need washers, screws will just go straight through...

 

[theandroids]

If Insulation board like marmox...then you definitely need washers, screws will just go straight through...

Thanks. What size screws would you recommend going into solid a wall?

 

[dannyeverton]

You need washers for any mechanical fixings with those type of board. 6mm needs to be stuck with a solid bed of tile adhesive. Only really suitable for overboarding a skimmed wall or alike. Thicker boards can be dot and dabbed then fixings through the dots and the dabs!

 

[dannyeverton]

I have an uneven brick wall and also clinker block wall. I want to use 12mm jakoboard. Jako recommend 20mm if I dot and dab and screws. Can I scratch coat first with tile adhesive or bonding coat, let it dry, then a full bed of tile adhesive and the 12mm board on and screw? Thanks

 

[benchwarmer]

No! 20mm will barely tickle the brick?
12mm jacko +
Dot and dab =
At least 40/50 mm screws!
Minimum mate