Damp course injection kit hire

[Joe Malone]

I am quite staggered that anyone would consider hiring equipment and injecting walls in the absence of any evidence whatsoever that rising damp is present. Firstly, establish whether a physical damp proof course is present or not? How old is the property?

Follow one of two golden rules, if a physical DPC is installed then ensure that external finished floor levels are a minimum of 150mm below internal finished floor level. If no physical DPC is present then this requirement increases to 200mm. Once you have this ensure that wall bases are not painted or rendered over. Walls need to be bare to allow moisture to evaporate and this is the key to preventing rising damp, not installing an unnecessary retrofit chemical damp proof course. Breathability is the key to preventing damp in old stone properties, particularly sandstone and I wouldn't mind betting that at some point someone has tanked the internal walls with waterproof render or renovating plaster. If they have then it needs to come off, this type of treatment is completely inappropriate for this sort of building. I'm not against using Dryzone occasionally but it is rarely required.

 

[ottosump]

Pictures of external render

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• ottosump
• 20 Mar 2015
• 1

Untitled

• ottosump
• 20 Mar 2015
• 1

Untitled

• ottosump
• 20 Mar 2015
• 1

 

[Joe Malone]

The external render is a mess, no wonder the walls are damp. I am not convinced you are dealing with sandstone walls here. Also what are the internal floors, concrete or timber. What year was it constructed?
My advice would be to expose an area of masonry below the render to see what you are dealing with. External render down to the floor will cause damp and the problem is compounded by the fact that someone has applied a coat of black impermeable paint. What is the difference between internal and external finished floor level?