Liquid DPM

rush1884 · Post by **rush1884** » Fri Jul 02, 2021 7:49 am

Currently renovating a 120 year old stone wall terrace. Damp situation isn’t too bad in the house. Some rising damp that pretty much ends at skirting board level. Ive knocked that off. I have already put some self levelling down on the floor as it was all over the place but now I’m consudering whether to put down a liquid DPM before second lot of self levelling. Fairly belt and braces stuff as I’m battening all downstairs walls to dry line. Therefore rising damp up those walls isn’t too much of an issue until it attacks the battens (which I can DPM anyway).

My question is, is it worth liquid DPM the floor and if so what sort of product would people recommend?

aeromech3 · Post by **aeromech3** » Fri Jul 02, 2021 9:52 am

Self levelling screeds need a DPM at some point below them, other wise they will likely de-bond due to rising damp. Don't know where this leaves you, as you did not mention the type of floor or primer before your first application of self levelling. See this old thread:-
viewtopic.php?t=55086

rush1884 · Post by **rush1884** » Fri Jul 02, 2021 10:18 am

I did 2 Coates of CEMENTONE SBR primer. Would you suggest now a layer of liquid DPM then another layer of self levelling?

Confused with the products though. Done are like emulsion and others you initially trowel I’m therefore seem a lot thicker

aeromech3 · Post by **aeromech3** » Fri Jul 02, 2021 11:08 am

I think you will find the emulsion types need two coats, after DPM then depends on what flooring your doing?

rush1884 · Post by **rush1884** » Fri Jul 02, 2021 12:21 pm

Carpet in one room and either laminate or tile in the other. So would you say 2 coats of liquid DPM (emulsion type) then layer of self levelling on top?

aeromech3 · Post by **aeromech3** » Sat Jul 03, 2021 12:21 pm

Whilst this sounds good, firstly what SL have you used already? Most liquid DPM's are designed to adhere to a cement base and then some SL's are not good on some liquid DPM's!
Have you considered that some carpet and laminate underlays are backed suitable to act as a DPM ?
When you think about commercial buildings, a concrete based slab is put down maybe +10 to 15cm; the builders are not going to wait months to progress, no, for carpet and laminate they put another barrier a damp proof underlay, yes it effectively seals in the moisture in the slab but that is what they get away with.