The Choice of DPC's

Installing a new DPC

The Choice of DPC's is broken into 2 main categories, "traditional" and "non traditional"

Traditional

Otherwise known as undersetting, where the base of the affected wall is rebuilt and a new plastic DPC is inserted. This method is very efficient and at the same time very expensive. Also it can only be placed in brickwork or coursed stonework and is not suitable for rubble walls or random stone walls whereas non traditional DPC’s can be used in most structures.

Non traditional

Otherwise known as chemical injection systems, have (prior to the conception of creams) been carried out by introducing silicones into the wall via a paraffin based carrier. This in turn is injected either under pressure or by gravity feed via bottles into evenly spaced holes drilled at the base of the wall. It is considered that gravity feed gives a more even penetration as fluid pumped in under pressure will naturally take the course of least resistance and follow any fissures or cracks in the wall. Whilst being efficient this method is time consuming, messy, smelly and more recently proven to be dangerous with a house being demolished by an explosion in South Australia due to poor safety procedures by the installer (see attached link for report in the Adelaide Advertiser here. )

Dryzone however uses a water based concentrated viscous silane/siloxane emulsion, otherwise known as a cream, inserted by a low pressure gun through 12mm diameter holes drilled at the base of the wall at 100mm intervals. No carrier fluid is used so the curing process is more even and rapid. It is safe, green, clean, non toxic and has no smell which enables the home owner to occupy any room treated the same day.

DRYZONE










Full Strength Damp Proofing

Dryzone damp-proofing cream has been formulated with a high concentration of active ingredient (over 60% silicone). This high level of active ingredient is necessary to ensure that:

• The active ingredient (silicone) spreads adequately between injection holes - ensuring that there are no significant gaps in the treatment through which damp can rise.

• Enough active ingredient (silicone) is introduced to the wall to give a comparable level of treatment to that provided by the traditional silicone injection systems (approx. 100g of silicone per metre of 9" wall). Silicone treatments carried out at this level since the 1950s have been proven to provide long-term protection against rising damp.

Further information and documentation of Dryzone damp-proofing cream can be found here.