How dry is dry enough?

[Jv40]

Hi all

How long after newly plastering a wall can you tile onto it? Say if its dry enough to prime-paint, does that automatically mean its dry enough to tile?
Thanks
Julia

[Fekin]

Normally 4 weeks I think.... obviously depending on how thick the coat is.

[whitebeam]

If it's a skim coat on new plasterboard and in a warm room give it a week, But if it has been pva,d and skimmed Id go for a 10 days. Float and set and on thermolite blocks your,ll it will dry very quick, Wait 3-4 weeks. Bonding undercoat on pva on concrete 4 weeks+

[Jv40]

Thank you but can you tell me why it varies so much and how will I be able to tell by looking at it myself. I accept what you say but when it comes to dealing with the builder I always have an argument on my hands if I say something can't be done now when he thinks it can.

[Dave]

It not only has to dry it has to gain strength as well....... for a skim on plasterboard i would leave it at least a week or so as whitebeam sez.......longer if thicker or 2 coat....

[whitebeam]

Usually if you look at the bottom of the wall plasterers tend to leave a gap between wall and floor from there you will see what has been used. The reason it varies is the back ground, In most plastering on new or refurb work tends to be dry linning

Solid backgrounds with moderate suction-browning
Low suction backgrounds eg;concrete, plasterboard and surfaces with pva-bonding plaster

When a pva is apllied the plaster has to dry out thru the surface, If the background has suction it will dry thru the wall and surface drying

Hope this helps but post if you want more answers

[Jv40]

Thank you for spelling it out whitebeam, that's very useful background information and all makes sense to me.